# MCP Agent Mail

![Agent Mail Showcase](screenshots/output/agent_mail_showcase.gif)

> "It's like gmail for your coding agents!"

## Fork Improvements

This fork extends the [original MCP Agent Mail](https://github.com/Dicklesworthstone/mcp_agent_mail) with several production-ready enhancements:

- **🚀 Lazy Loading System (Phase 2)** - Reduces token usage by ~65% with core mode (10 essential tools vs. 27), plus meta-tools (`list_extended_tools`, `call_extended_tool`) for dynamic tool discovery and invocation
- **🎯 Globally Unique Agent Names** - Prevents agent name confusion across projects with database-enforced uniqueness, flexible coerce/strict enforcement modes, and automatic migration for existing deployments
- **⚡ Simplified Registration** - `register_agent` now auto-creates projects, eliminating the need for separate `ensure_project` calls in most workflows
- **🔧 Flexible Project Keys** - Supports any string identifier (repo names, custom IDs) as project keys, not just absolute paths
- **💬 Contact-Free Messaging** - Direct agent-to-agent messaging without contact request approval, streamlining multi-agent coordination

These improvements make the system more efficient, flexible, and easier to use in production multi-agent workflows.

---

A mail-like coordination layer for coding agents, exposed as an HTTP-only FastMCP server. It gives agents memorable identities, an inbox/outbox, searchable message history, and voluntary file reservation "leases" to avoid stepping on each other.

Think of it as asynchronous email + directory + change-intent signaling for your agents, backed by Git (for human-auditable artifacts) and SQLite (for indexing and queries).

Status: Under active development. The design is captured in detail in `project_idea_and_guide.md` (start with the original prompt at the top of that file).

## Why this exists

Modern projects often run multiple coding agents at once (backend, frontend, scripts, infra). Without a shared coordination fabric, agents:

- Overwrite each other's edits or panic on unexpected diffs
- Miss critical context from parallel workstreams
- Require humans to "liaison" messages across tools and teams

This project provides a lightweight, interoperable layer so agents can:

- Register a temporary-but-persistent identity (e.g., GreenCastle)
- Send/receive GitHub-Flavored Markdown messages with images
- Search, summarize, and thread conversations
- Declare advisory file reservations (leases) on files/globs to signal intent
- Inspect a directory of active agents, programs/models, and activity

It's designed for: FastMCP clients and CLI tools (Claude Code, Codex, Gemini CLI, etc.) coordinating across one or more codebases.

## TLDR Quickstart

### One-line installer

```bash
curl -fsSL https://raw.githubusercontent.com/Dicklesworthstone/mcp_agent_mail/main/scripts/install.sh | bash -s -- --yes
```

What this does:

- Installs uv if missing and updates your PATH for this session
- Creates a Python 3.14 virtual environment and installs dependencies with uv
- Runs the auto-detect integration to wire up supported agent tools
- Starts the MCP HTTP server on port 8765 and prints a masked bearer token
- Creates helper scripts under `scripts/` (including `run_server_with_token.sh`)

Prefer a specific location or options? Add flags like `--dir <path>`, `--project-dir <path>`, `--no-start`, `--start-only`, `--port <number>`, or `--token <hex>`.

**Port conflicts?** Use `--port` to specify a different port (default: 8765):

```bash
# Install with custom port
curl -fsSL https://raw.githubusercontent.com/Dicklesworthstone/mcp_agent_mail/main/scripts/install.sh | bash -s -- --port 9000 --yes

# Or use the CLI command after installation
uv run python -m mcp_agent_mail.cli config set-port 9000
```

### If you want to do it yourself

Clone the repo, set up and install with uv in a python 3.14 venv (install uv if you don't have it already), and then run `scripts/automatically_detect_all_installed_coding_agents_and_install_mcp_agent_mail_in_all.sh`. This will automatically set things up for your various installed coding agent tools and start the MCP server on port 8765. If you want to run the MCP server again in the future, simply run `scripts/run_server_with_token.sh`:

```bash
# Install uv (if you don't have it already)
curl -LsSf https://astral.sh/uv/install.sh | sh
export PATH="$HOME/.local/bin:$PATH"

# Clone the repo
git clone https://github.com/Dicklesworthstone/mcp_agent_mail
cd mcp_agent_mail

# Create a Python 3.14 virtual environment and install dependencies
uv python install 3.14
uv venv -p 3.14
source .venv/bin/activate
uv sync

# Detect installed coding agents, integrate, and start the MCP server on port 8765
scripts/automatically_detect_all_installed_coding_agents_and_install_mcp_agent_mail_in_all.sh

# Later, to run the MCP server again with the same token
scripts/run_server_with_token.sh

# Now, simply launch Codex-CLI or Claude Code or other agent tools in other consoles; they should have the mail tool available. See below for a ready-made chunk of text you can add to the end of your existing AGENTS.md or CLAUDE.md files to help your agents better utilize the new tools.

# Change port after installation
uv run python -m mcp_agent_mail.cli config set-port 9000
```

## Ready-Made Blurb to Add to Your AGENTS.md or CLAUDE.md Files:
```
## MCP Agent Mail: coordination for multi-agent workflows

What it is
- A mail-like layer that lets coding agents coordinate asynchronously via MCP tools and resources.
- Provides identities, inbox/outbox, searchable threads, and advisory file reservations, with human-auditable artifacts in Git.

Why it's useful
- Prevents agents from stepping on each other with explicit file reservations (leases) for files/globs.
- Keeps communication out of your token budget by storing messages in a per-project archive.
- Offers quick reads (`resource://inbox/...`, `resource://thread/...`) and macros that bundle common flows.

How to use effectively
1) Same repository
   - Register an identity: call `ensure_project`, then `register_agent` using this repo's absolute path as `project_key`.
   - Reserve files before you edit: `file_reservation_paths(project_key, agent_name, ["src/**"], ttl_seconds=3600, exclusive=true)` to signal intent and avoid conflict.
   - Communicate with threads: use `send_message(..., thread_id="FEAT-123")`; check inbox with `fetch_inbox` and acknowledge with `acknowledge_message`.
   - Read fast: `resource://inbox/{Agent}?project=<abs-path>&limit=20` or `resource://thread/{id}?project=<abs-path>&include_bodies=true`.
   - Tip: set `AGENT_NAME` in your environment so the pre-commit guard can block commits that conflict with others' active exclusive file reservations.

2) Across different repos in one project (e.g., Next.js frontend + FastAPI backend)
   - Option A (single project bus): register both sides under the same `project_key` (shared key/path). Keep reservation patterns specific (e.g., `frontend/**` vs `backend/**`).
   - Option B (separate projects): each repo has its own `project_key`; agents can message each other directly using `send_message` with cross-project addressing. Keep a shared `thread_id` (e.g., ticket key) across repos for clean summaries/audits.

Macros vs granular tools
- Prefer macros when you want speed or are on a smaller model: `macro_start_session`, `macro_prepare_thread`, `macro_file_reservation_cycle`, `macro_contact_handshake`.
- Use granular tools when you need control: `register_agent`, `file_reservation_paths`, `send_message`, `fetch_inbox`, `acknowledge_message`.

Common pitfalls
- "from_agent not registered": always `register_agent` in the correct `project_key` first.
- "FILE_RESERVATION_CONFLICT": adjust patterns, wait for expiry, or use a non-exclusive reservation when appropriate.
- Auth errors: if JWT+JWKS is enabled, include a bearer token with a `kid` that matches server JWKS; static bearer is used only when JWT is disabled.
```

## Integrating with Beads (dependency-aware task planning)

Beads is a lightweight task planner (`bd` CLI) that complements Agent Mail by keeping status and dependencies in one place while Mail handles messaging, file reservations, and audit trails. Project: [steveyegge/beads](https://github.com/steveyegge/beads)

Highlights:
- Beads owns task prioritization; Agent Mail carries the conversations and artifacts.
- Shared identifiers (e.g., `bd-123`) keep Beads issues, Mail threads, and commits aligned.
- Install the `bd` CLI via prebuilt release or Go build; see the repository for platform specifics.

Copy/paste blurb for agent-facing docs (leave as-is for reuse):

```

## Integrating with Beads (dependency-aware task planning)

Beads provides a lightweight, dependency-aware issue database and a CLI (`bd`) for selecting "ready work," setting priorities, and tracking status. It complements MCP Agent Mail's messaging, audit trail, and file-reservation signals. Project: [steveyegge/beads](https://github.com/steveyegge/beads)

Recommended conventions
- **Single source of truth**: Use **Beads** for task status/priority/dependencies; use **Agent Mail** for conversation, decisions, and attachments (audit).
- **Shared identifiers**: Use the Beads issue id (e.g., `bd-123`) as the Mail `thread_id` and prefix message subjects with `[bd-123]`.
- **Reservations**: When starting a `bd-###` task, call `file_reservation_paths(...)` for the affected paths; include the issue id in the `reason` and release on completion.

Typical flow (agents)
1) **Pick ready work** (Beads)
   - `bd ready --json` → choose one item (highest priority, no blockers)
2) **Reserve edit surface** (Mail)
   - `file_reservation_paths(project_key, agent_name, ["src/**"], ttl_seconds=3600, exclusive=true, reason="bd-123")`
3) **Announce start** (Mail)
   - `send_message(..., thread_id="bd-123", subject="[bd-123] Start: <short title>", ack_required=true)`
4) **Work and update**
   - Reply in-thread with progress and attach artifacts/images; keep the discussion in one thread per issue id
5) **Complete and release**
   - `bd close bd-123 --reason "Completed"` (Beads is status authority)
   - `release_file_reservations(project_key, agent_name, paths=["src/**"])`
   - Final Mail reply: `[bd-123] Completed` with summary and links

Mapping cheat-sheet
- **Mail `thread_id`** ↔ `bd-###`
- **Mail subject**: `[bd-###] …`
- **File reservation `reason`**: `bd-###`
- **Commit messages (optional)**: include `bd-###` for traceability

Event mirroring (optional automation)
- On `bd update --status blocked`, send a high-importance Mail message in thread `bd-###` describing the blocker.
- On Mail "ACK overdue" for a critical decision, add a Beads label (e.g., `needs-ack`) or bump priority to surface it in `bd ready`.

Pitfalls to avoid
- Don't create or manage tasks in Mail; treat Beads as the single task queue.
- Always include `bd-###` in message `thread_id` to avoid ID drift across tools.

```

## Core ideas (at a glance)

- HTTP-only FastMCP server (Streamable HTTP). No SSE, no STDIO.
- Dual persistence model:
  - Human-readable markdown in a per-project Git repo for every canonical message and per-recipient inbox/outbox copy
  - SQLite with FTS5 for fast search, directory queries, and file reservations/leases
- "Directory/LDAP" style queries for agents; auto-generated adjective+noun codenames keep things memorable (custom alphanumeric names are also allowed)
- Advisory file reservations for editing surfaces; optional pre-commit guard
- Resource layer for convenient reads (e.g., `resource://inbox/{agent}`)

## Typical use cases

- Multiple agents splitting a large refactor across services while staying in sync
- Frontend and backend teams of agents coordinating thread-by-thread
- Protecting critical migrations with exclusive file reservations and a pre-commit guard
- Searching and summarizing long technical discussions as threads evolve
- Discovering and linking related projects (e.g., frontend/backend) through AI-powered suggestions

## Architecture

```mermaid
graph LR
  A[Agents]
  S[Server]
  G[Git repo]
  Q[SQLite FTS5]

  A -->|HTTP tools/resources| S
  S -->|writes/reads| G
  S -->|indexes/queries| Q

  subgraph GitTree["Git tree"]
    GI1[agents/profile.json]
    GI2[agents/mailboxes/...]
    GI3[messages/YYYY/\nMM/\nid.md]
    GI4[file_reservations/\nsha1.json]
    GA[attachments/xx/\nsha1.webp]
  end

  G --- GI1
  G --- GI2
  G --- GI3
  G --- GI4
  G --- GA
```

## Web UI (human-facing mail viewer)

The server ships a lightweight, server-rendered Web UI for humans. It lets you browse projects, agents, inboxes, single messages, attachments, file reservations, and perform full-text search with FTS5 when available (with an automatic LIKE fallback).

- Where it lives: built into the HTTP server in `mcp_agent_mail.http` under the `/mail` path.
- Who it's for: humans reviewing activity; agents should continue to use the MCP tools/resources API.

### Launching the Web UI

Recommended (simple):

```bash
scripts/run_server_with_token.sh
# then open http://127.0.0.1:8765/mail
```

Advanced (manual commands):

```bash
uv run python -m mcp_agent_mail.http --host 127.0.0.1 --port 8765
# or:
uv run uvicorn mcp_agent_mail.http:build_http_app --factory --host 127.0.0.1 --port 8765
```

Auth notes:
- GET pages in the UI are not gated by the RBAC middleware (it classifies POSTed MCP calls only), but if you set a bearer token the separate BearerAuth middleware protects all routes by default.
- For local dev, set `HTTP_ALLOW_LOCALHOST_UNAUTHENTICATED=true` (and optionally `HTTP_BEARER_TOKEN`), so localhost can load the UI without headers.
- Health endpoints are always open at `/health/*`.

### Routes and what you can do

- `/mail` (Unified inbox + Projects + Related Projects Discovery)
  - Shows a unified, reverse-chronological inbox of recent messages across all projects with excerpts, relative timestamps, sender/recipients, and project badges.
  - Below the inbox, lists all projects (slug, human name, created time) with sibling suggestions.
  - Suggests **likely sibling projects** when two slugs appear to be parts of the same product (e.g., backend vs. frontend). Suggestions are ranked with heuristics and, when `LLM_ENABLED=true`, an LLM pass across key docs (`README.md`, `AGENTS.md`, etc.).
  - Humans can **Confirm Link** or **Dismiss** suggestions from the dashboard. Confirmed siblings become highlighted badges for organizational clarity. Agents can message across projects directly without requiring contact approval.

- `/mail/projects` (Projects index)
  - Dedicated projects list view; click a project to drill in.

- `/mail/{project}` (Project overview + search + agents)
  - Rich search form with filters:
    - Scope: subject/body/both, Order: relevance or time, optional "boost subject".
    - Query tokens: supports `subject:foo`, `body:"multi word"`, quoted phrases, and bare terms.
    - Uses FTS5 bm25 scoring when available; otherwise falls back to SQL LIKE on subject/body with your chosen scope.
  - Results show subject, sender, created time, thread id, and a highlighted snippet when using FTS.
  - Agents panel shows registered agents for the project with a link to each inbox.
  - Quick links to File Reservations and Attachments for the project header.

- `/mail/{project}/inbox/{agent}` (Inbox for one agent)
  - Reverse-chronological list with subject, sender, created time, importance badge, thread id.
  - Pagination (`?page=N&limit=M`).

- `/mail/{project}/message/{id}` (Message detail)
  - Shows subject, sender, created time, importance, recipients (To/Cc/Bcc), thread messages.
  - Body rendering:
    - If the server pre-converted markdown to HTML, it's sanitized with Bleach (limited tags/attributes, safe CSS via CSSSanitizer) and then displayed.
    - Otherwise markdown is rendered client-side with Marked + Prism for code highlighting.
  - Attachments are referenced from the message frontmatter (WebP files or inline data URIs).

- `/mail/{project}/search?q=...` (Dedicated search page)
  - Same query syntax as the project overview search, with a token "pill" UI for assembling/removing filters.

- `/mail/{project}/file_reservations` (File Reservations list)
  - Displays active and historical file reservations (exclusive/shared, path pattern, timestamps, released/expired state).

- `/mail/{project}/attachments` (Messages with attachments)
  - Lists messages that contain any attachments, with subject and created time.
  
- `/mail/unified-inbox` (Cross-project activity)
  - Shows recent messages across all projects with thread counts and sender/recipients.

### Human Overseer: Sending Messages to Agents

Sometimes a human operator needs to guide or redirect agents directly, whether to handle an urgent issue, provide clarification, or adjust priorities. The **Human Overseer** feature provides a web-based message composer that lets humans send high-priority messages to any combination of agents in a project.

**Access:** Click the prominent **"Send Message"** button (with the Overseer badge) in the header of any project view (`/mail/{project}`), or navigate directly to `/mail/{project}/overseer/compose`.

#### What Makes Overseer Messages Special

1. **Automatic Preamble**: Every message includes a formatted preamble that clearly identifies it as coming from a human operator and instructs agents to:
   - **Pause current work** temporarily
   - **Prioritize the human's request** over existing tasks
   - **Resume original plans** afterward (unless modified by the instructions)

2. **High Priority**: All overseer messages are automatically marked as **high importance**, ensuring they stand out in agent inboxes.

3. **Policy Bypass**: Overseer messages bypass normal contact policies, so humans can always reach any agent regardless of their contact settings.

4. **Special Sender Identity**: Messages come from a special agent named **"HumanOverseer"** (automatically created per project) with:
   - Program: `WebUI`
   - Model: `Human`
   - Contact Policy: `open`

#### The Message Preamble

Every overseer message begins with this preamble (automatically prepended):

```
---

🚨 MESSAGE FROM HUMAN OVERSEER 🚨

This message is from a human operator overseeing this project. Please prioritize
the instructions below over your current tasks.

You should:
1. Temporarily pause your current work
2. Complete the request described below
3. Resume your original plans afterward (unless modified by these instructions)

The human's guidance supersedes all other priorities.

---

[Your message body follows here]
```

#### Using the Composer

The composer interface provides:

- **Recipient Selection**: Checkbox grid of all registered agents (with "Select All" / "Clear" shortcuts)
- **Subject Line**: Required, shown in agent inboxes
- **Message Body**: GitHub-flavored Markdown editor with preview
- **Thread ID** (optional): Continue an existing conversation or start a new one
- **Preamble Preview**: See exactly how your message will appear to agents

#### Example Use Cases

**Urgent Issue:**
```
Subject: Urgent: Stop migration and revert changes

The database migration in PR #453 is causing data corruption in staging.

Please:
1. Immediately stop any migration-related work
2. Revert commits from the last 2 hours
3. Wait for my review before resuming

I'm investigating the root cause now.
```

**Priority Adjustment:**
```
Subject: New Priority: Security Vulnerability

A critical security vulnerability was just disclosed in our auth library.

Drop your current tasks and:
1. Update `auth-lib` to version 2.4.1 immediately
2. Review all usages in src/auth/
3. Run the full security test suite
4. Report status in thread #892

This takes precedence over the refactoring work.
```

**Clarification:**
```
Subject: Clarification on API design approach

I see you're debating REST vs. GraphQL in thread #234.

Go with REST for now because:
- Our frontend team has more REST experience
- GraphQL adds complexity we don't need yet
- We can always add GraphQL later if needed

Resume the API implementation with REST.
```

#### How Agents See Overseer Messages

When agents check their inbox (via `fetch_inbox` or `resource://inbox/{name}`), overseer messages appear like any other message but with:

- **Sender**: `HumanOverseer`
- **Importance**: `high` (displayed prominently)
- **Body**: Starts with the overseer preamble, followed by the human's message
- **Visual cues**: In the Web UI, these messages may have special highlighting (future enhancement)

Agents can reply to overseer messages just like any other message, continuing the conversation thread.

#### Technical Details

- **Storage**: Overseer messages are stored identically to agent-to-agent messages (Git + SQLite)
- **Git History**: Fully auditable; message appears in `messages/YYYY/MM/{id}.md` with commit history
- **Thread Continuity**: Can be part of existing threads or start new ones
- **No Authentication Bypass**: The overseer compose form still requires proper HTTP server authentication (if enabled)

#### Design Philosophy

The Human Overseer feature is designed to be:

- **Explicit**: Agents clearly know when guidance comes from a human vs. another agent
- **Respectful**: Instructions acknowledge agents have existing work and shouldn't just "drop everything" permanently
- **Temporary**: Agents are told to resume original plans once the human's request is complete
- **Flexible**: Humans can override this guidance directly in their message body

This creates a clear hierarchy (human → agents) while maintaining the collaborative, respectful tone of the agent communication system.

### Related Projects Discovery

The Projects index (`/mail`) features an **AI-powered discovery system** that intelligently suggests which projects should be linked together, such as frontend + backend or related microservices.

#### How Discovery Works

**1. Smart Analysis**
The system uses multiple signals to identify relationships:
- **Pattern matching**: Compares project names and paths (e.g., "my-app-frontend" ↔ "my-app-backend")
- **AI understanding** (when `LLM_ENABLED=true`): Reads `README.md`, `AGENTS.md`, and other docs to understand each project's purpose and detect natural relationships
- **Confidence scoring**: Ranks suggestions from 0-100% with clear rationales

**2. Beautiful Suggestions**
Related projects appear as polished cards on your dashboard with:
- 🎯 Visual confidence indicators showing match strength
- 💬 AI-generated rationales explaining the relationship
- ✅ **Confirm Link** - accept the suggestion
- ✖️ **Dismiss** - hide irrelevant matches

**3. Quick Navigation**
Once confirmed, both projects display interactive badges for instant navigation between related codebases.

#### Why Suggestions, Not Auto-Linking?

> **TL;DR**: We keep you in control. Discovery helps you find relationships; explicit approvals control who can actually communicate.

**Agent Mail uses agent-centric messaging**: every message follows explicit permission chains:

```
Send Message → Find Recipient → Check AgentLink Approval → Deliver
```

This design ensures:
- **Security**: No accidental cross-project message delivery
- **Transparency**: You always know who can talk to whom
- **Audit trails**: All communication paths are explicitly approved

**Why not auto-link with AI?**
If we let an LLM automatically authorize messaging between projects, we'd be:
- ❌ Bypassing contact policies without human oversight
- ❌ Risking message misdelivery to unintended recipients
- ❌ Creating invisible routing paths that are hard to audit
- ❌ Potentially linking ambiguously-named projects incorrectly

Instead, we give you **discovery + control**:
- ✅ AI suggests likely relationships (safe, read-only analysis)
- ✅ You confirm what makes sense (one click)
- ✅ Confirmed links update UI badges for better organization
- ✅ Agents can message across projects directly without additional approval

#### The Workflow

```text
1. System suggests: "These projects look related" (AI analysis)
           ↓
2. You confirm: "Yes, link them" (updates UI badges for clarity)
           ↓
3. Agents communicate: send_message with cross-project addressing
```

**NOTE:** Contact approval is no longer required. Agents can send messages across projects directly.

### Search syntax (UI)

The UI shares the same parsing as the API's `_parse_fts_query`:
- Field filters: `subject:login`, `body:"api key"`
- Phrase search: `"build plan"`
- Combine terms: `login AND security` (FTS)
- Fallback LIKE: scope determines whether subject, body, or both are searched

### Prerequisites to see data

The UI reads from the same SQLite + Git artifacts as the MCP tools. To populate content:
1) Ensure a project exists (via tool call or CLI):
   - Ensure/create project: `ensure_project(human_key)`
2) Register one or more agents: `register_agent(project_key, program, model, name?)`
3) Send messages: `send_message(...)` (attachments and inline images are supported; images may be converted to WebP).

Once messages exist, visit `/mail`, click your project, then open an agent inbox or search.

### Implementation and dependencies

- Templates live in `src/mcp_agent_mail/templates/` and are rendered by Jinja2.
- Markdown is converted with `markdown2` on the server where possible; HTML is sanitized with Bleach (with CSS sanitizer when available).
- Tailwind CSS, Lucide icons, Alpine.js, Marked, and Prism are loaded via CDN in `base.html` for a modern look without a frontend build step.
- All rendering is server-side; there's no SPA router. Pages degrade cleanly without JavaScript.

### Security considerations

- HTML sanitization: Only a conservative set of tags/attributes are allowed; CSS is filtered. Links are limited to http/https/mailto/data.
- Auth: Use bearer token or JWT when exposing beyond localhost. For local dev, enable localhost bypass as noted above.
- Rate limiting (optional): Token-bucket limiter can be enabled; UI GET requests are light and unaffected by POST limits.

### Troubleshooting the UI

- Blank page or 401 on localhost: Either unset `HTTP_BEARER_TOKEN` or set `HTTP_ALLOW_LOCALHOST_UNAUTHENTICATED=true`.
- No projects listed: Create one with `ensure_project`.
- Empty inbox: Verify recipient names match exactly and messages were sent to that agent.
- Search returns nothing: Try simpler terms or the LIKE fallback (toggle scope/body).

## Static Mailbox Export (Share & Distribute Archives)

The `share` command group provides a complete pipeline for exporting mailbox archives into self-contained static HTML bundles. These bundles can be distributed to stakeholders, auditors, or team members who need read-only access to message history without running the full MCP Agent Mail server.

### Why export to static bundles?

**Compliance and audit trails**: Deliver immutable snapshots of project communication to auditors or compliance officers. The static bundle includes cryptographic signatures for tamper-evident distribution.

**Stakeholder review**: Share conversation history with product managers, executives, or external consultants who don't need write access. They can browse messages, search threads, and view attachments in their browser without authentication.

**Offline access**: Create portable archives for air-gapped environments, disaster recovery backups, or situations where internet connectivity is unreliable.

**Long-term archival**: Preserve project communication in a format that will remain readable decades from now. Static HTML requires no database server, no runtime dependencies, and survives software obsolescence better than proprietary formats.

**Secure distribution**: Encrypt bundles with age for confidential projects. Only recipients with the private key can decrypt and view the contents.

### What's included in an export

Each bundle contains:

- **Static HTML viewer**: A single-page application with three-pane interface (projects, threads, messages) that runs entirely in the browser. No server required after the initial file serving.
- **SQLite database snapshot**: A read-only copy of the messages, agents, and metadata, loaded via SQL.js (WebAssembly).
- **Full-text search**: FTS5 search index embedded in the database allows fast subject/body searches entirely client-side.
- **Attachments**: Images and files, either bundled directly (for small files) or marked as external references (for large files).
- **Integrity metadata**: SHA-256 hashes for all assets (vendor libraries, database, attachments) stored in `manifest.json` for verification.
- **Optional signature**: Ed25519 cryptographic signature over the manifest to prove authenticity and detect tampering.
- **Security hardening**: Content Security Policy headers, DOMPurify sanitization, and Trusted Types enforcement protect against XSS attacks in message bodies.

### Quick Start: Interactive Deployment Wizard

The easiest way to export and deploy is the interactive wizard, which supports both GitHub Pages and Cloudflare Pages:

```bash
# Via CLI (recommended)
uv run python -m mcp_agent_mail.cli share wizard

# Or run the script directly
./scripts/share_to_github_pages.py
```

#### What the wizard does

The wizard provides a fully automated end-to-end deployment experience:

1. **Configuration management**: Remembers your last settings and offers to reuse them, saving time on repeated exports
2. **Deployment target selection**: Choose between GitHub Pages, Cloudflare Pages, or local export
3. **Automatic CLI installation**: Detects and installs missing tools (`gh` for GitHub, `wrangler` for Cloudflare)
4. **Guided authentication**: Step-by-step browser login flows for GitHub and Cloudflare
5. **Smart project selection**:
   - Shows all available projects in a formatted table
   - Supports multiple selection modes: `all`, single number (`1`), lists (`1,3,5`), or ranges (`1-3`, `2-5,8`)
   - Remembers your previous selection for quick re-export
6. **Redaction configuration**: Choose between `standard` (scrub secrets like API keys/tokens, keep agent names) or `strict` (redact all message bodies)
7. **Cryptographic signing**: Optional Ed25519 signing with automatic key generation or use your existing key
8. **Pre-flight validation**: Checks that GitHub repo names are available before starting the export
9. **Deployment summary**: Shows what will be deployed (project count, bundle size, target, signing status) and asks for confirmation
10. **Export and preview**: Exports the bundle and launches a local preview server with automatic port detection (tries 9000-9100)
11. **Real-time deployment**: Streams git and deployment output in real-time so you can follow the progress
12. **Automatic deployment**: Creates repos, enables Pages, pushes code, and gives you the live URL

#### Configuration persistence

The wizard saves your configuration to `~/.mcp-agent-mail/wizard-config.json` after each successful deployment. On subsequent runs, it will show:

```
Previous Configuration Found
  Projects: 3 selected
  Redaction: standard
  Target: github-new

Use these settings again? (Y/n):
```

This allows rapid re-deployment with the same settings. The saved configuration includes:
- Selected project indices (validates against current project list)
- Redaction preset
- Deployment target and parameters (repo name, privacy, project name)
- Signing preferences (whether to sign, whether to generate new key)

Configuration is project-agnostic: if you add or remove projects, the wizard validates saved indices and prompts for re-selection if needed.

#### Multi-project selection

The project selector supports flexible selection syntax:

```
Available Projects:
#  Slug                Path
1  backend-abc123      /abs/path/backend
2  frontend-xyz789     /abs/path/frontend
3  infra-def456        /abs/path/infra
4  scripts-ghi789      /abs/path/scripts

Select projects to export (e.g., 'all', '1,3,5', or '1-3'):
```

**Selection modes:**
- `all`: Export all projects (default)
- `1`: Export project #1 only
- `1,3,5`: Export projects #1, #3, and #5
- `1-3`: Export projects #1, #2, and #3 (inclusive range)
- `2-4,7`: Export projects #2, #3, #4, and #7 (combined range and list)

Invalid selections (out of range, malformed) are rejected with helpful error messages and the wizard prompts again.

#### Dynamic port allocation

The preview server automatically detects an available port in the range 9000-9100 instead of failing if port 9000 is in use. The actual port is displayed:

```
Launching preview server...
Using port 9001 (Ctrl+C to stop server)
Waiting for server to start...
✓ Server ready, opening browser at http://127.0.0.1:9001
```

This prevents port conflicts when multiple previews are running or when port 9000 is used by other services.

#### Deployment summary panel

Before starting the export, the wizard shows a comprehensive summary:

```
═══ Deployment Summary ═══

Projects: 3 selected
Bundle size: ~32 MB
Redaction: standard
Target: GitHub Pages
  Repository: mailbox-viewer-2024
  Visibility: Private
Signing: Enabled (Ed25519)

Proceed with export and deployment? (Y/n):
```

This gives you a final chance to review all settings and cancel if needed. The bundle size is estimated based on ~10 MB per project plus ~2 MB for static assets.

#### Real-time deployment streaming

Git operations and Cloudflare deployments stream output in real-time so you can see exactly what's happening:

```
Initializing git repository and pushing...
Initializing repository...
  Initialized empty Git repository in /tmp/mailbox-preview-abc123/.git/
✓ Initializing repository complete
Adding files...
✓ Adding files complete
Creating commit...
  [main (root-commit) 1a2b3c4] Initial mailbox export
   425 files changed, 123456 insertions(+)
✓ Creating commit complete
Pushing to GitHub...
  Enumerating objects: 430, done.
  Counting objects: 100% (430/430), done.
  Delta compression using up to 8 threads
  Compressing objects: 100% (425/425), done.
  Writing objects: 100% (430/430), 12.34 MiB | 5.67 MiB/s, done.
✓ Pushing to GitHub complete

✓ Successfully pushed to owner/mailbox-viewer-2024
```

This provides transparency and helps diagnose issues if deployment fails.

#### Platform-specific details

**For GitHub Pages:**
- Wizard detects your package manager (brew/apt/dnf) and offers automated installation of `gh` CLI
- For apt/dnf, shows complete manual installation instructions (including repo setup) since automation requires sudo
- Runs `gh auth login` interactively to authenticate via browser
- Creates new repository with your specified name and visibility (public/private)
- Initializes git, commits, and pushes with streaming output
- Enables GitHub Pages automatically via the GitHub API
- Provides the GitHub Pages URL (may take 1-2 minutes to become live)

**For Cloudflare Pages:**
- Detects npm and offers automated installation of `wrangler` CLI
- Runs `wrangler login` interactively to authenticate via browser
- Deploys directly to Cloudflare's global CDN (no git repository needed)
- Streams wrangler output in real-time
- Provides the `.pages.dev` URL immediately (site is live instantly)
- Benefits: instant deployment, 275+ global locations, automatic HTTPS, unlimited requests on free tier

**For local export:**
- Saves bundle to specified directory
- No CLI installation or authentication required
- Suitable for manual deployment to custom hosting or inspection

#### Error handling and recovery

The wizard includes comprehensive error handling:

- **Pre-flight validation**: Checks GitHub repo availability before starting export to avoid conflicts
- **Port conflict resolution**: Automatically finds an available port for preview server
- **Invalid selection handling**: Validates project selections and prompts for correction
- **CLI installation failures**: Shows manual installation instructions if automatic installation fails
- **Git operation failures**: Each git step is validated; stops on first failure with clear error message
- **Deployment failures**: Distinguishes between repo creation, push, and Pages enablement failures

If deployment fails after export, the bundle remains in the temp directory and can be deployed manually using the git commands shown in the manual deployment section below.

The wizard handles all operations automatically. For manual control or advanced options, see the detailed workflows below.

### Basic export workflow (manual)

**1. Export a bundle**

```bash
# Export all projects to a directory
uv run python -m mcp_agent_mail.cli share export --output ./my-bundle

# Export specific projects only
uv run python -m mcp_agent_mail.cli share export \
  --output ./my-bundle \
  --project backend-abc123 \
  --project frontend-xyz789

# Export with Ed25519 signing for tamper-evident distribution
uv run python -m mcp_agent_mail.cli share export \
  --output ./my-bundle \
  --signing-key ./keys/signing.key \
  --signing-public-out ./keys/signing.pub

# Export and encrypt with age for secure distribution
uv run python -m mcp_agent_mail.cli share export \
  --output ./my-bundle \
  --age-recipient age1abc...xyz \
  --age-recipient age1def...uvw
```

The export process:

1. Creates a snapshot of the SQLite database (read-only, no WAL/SHM files)
2. Copies message bodies, attachments, and metadata into the bundle structure
3. Applies redaction rules based on the scrub preset (default: `standard`)
4. Generates `manifest.json` with SHA-256 hashes for all assets
5. Optionally signs the manifest with Ed25519 (produces `manifest.sig.json`)
6. Packages everything into a ZIP archive (optional, enabled by default)
7. Optionally encrypts the ZIP with age (produces `bundle.zip.age`)

**2. Preview locally**

```bash
# Serve the bundle on localhost:9000
uv run python -m mcp_agent_mail.cli share preview ./my-bundle

# Custom port and auto-open browser
uv run python -m mcp_agent_mail.cli share preview ./my-bundle \
  --port 8080 \
  --open-browser
```

This launches a lightweight HTTP server that serves the static files. Open `http://127.0.0.1:9000/` in your browser to explore the archive.

**3. Verify integrity**

```bash
# Verify SRI hashes and signature
uv run python -m mcp_agent_mail.cli share verify ./my-bundle

# Verify with explicit public key (overrides manifest.sig.json)
uv run python -m mcp_agent_mail.cli share verify ./my-bundle \
  --public-key AAAA...base64...
```

Verification checks:

- SHA-256 hashes for all vendor libraries (Marked.js, DOMPurify, SQL.js)
- SHA-256 hashes for the SQLite database and attachments
- Ed25519 signature over the canonical manifest (if present)

**4. Decrypt (if encrypted)**

```bash
# Decrypt with age identity file (private key)
uv run python -m mcp_agent_mail.cli share decrypt bundle.zip.age \
  --identity ~/.age/key.txt

# Decrypt with passphrase (interactive prompt)
uv run python -m mcp_agent_mail.cli share decrypt bundle.zip.age \
  --passphrase

# Specify custom output path
uv run python -m mcp_agent_mail.cli share decrypt bundle.zip.age \
  --output ./decrypted-bundle.zip \
  --identity ~/.age/key.txt
```

After decryption, unzip the archive and use `share preview` to view it.

### Export options reference

| Option | Type | Default | Description |
| :-- | :-- | :-- | :-- |
| `--output`, `-o` | Path | (required) | Directory where the static bundle will be written |
| `--project`, `-p` | List | All projects | Limit export to specific project slugs or human keys (repeatable) |
| `--inline-threshold` | Bytes | 65536 (64KB) | Inline attachments smaller than this as base64 data URIs |
| `--detach-threshold` | Bytes | 26214400 (25MB) | Mark attachments larger than this as external (not bundled) |
| `--scrub-preset` | String | `standard` | Redaction preset: `standard` or `strict` (see Redaction presets section) |
| `--chunk-threshold` | Bytes | 20971520 (20MB) | Split SQLite database into chunks if it exceeds this size |
| `--chunk-size` | Bytes | 4194304 (4MB) | Chunk size when splitting large databases |
| `--dry-run` | Flag | false | Generate security summary and preview without writing files |
| `--zip` / `--no-zip` | Flag | true | Package the bundle into a ZIP archive |
| `--signing-key` | Path | None | Path to Ed25519 signing key (32-byte raw seed) |
| `--signing-public-out` | Path | None | Write the Ed25519 public key to this file after signing |
| `--age-recipient` | String | None | age public key for encryption (repeatable for multiple recipients) |
| `--interactive`, `-i` | Flag | false | Launch interactive wizard (prints guidance; full wizard TBD) |

### Security features

**XSS protection (DOMPurify + Trusted Types)**

Message bodies are rendered using a defense-in-depth pipeline:

1. **Marked.js** parses GitHub-Flavored Markdown into HTML
2. **DOMPurify** sanitizes the HTML, removing dangerous tags and attributes
3. **Trusted Types** enforces that all `innerHTML` assignments use TrustedHTML objects
4. **Content Security Policy** blocks inline scripts, external resources, and unsafe-eval

This prevents malicious content in message bodies from executing JavaScript or exfiltrating data.

**Cryptographic signing (Ed25519)**

When you provide a signing key, the export process:

1. Generates a canonical JSON representation of `manifest.json`
2. Signs it with Ed25519 (fast, 64-byte signatures)
3. Writes the signature and public key to `manifest.sig.json`

Recipients can verify the signature using `share verify` to ensure:

- The bundle hasn't been modified since signing
- The bundle was created by someone with the private key
- All assets match their declared SHA-256 hashes

**Encryption (age)**

The `age` encryption tool (https://age-encryption.org/) provides modern, secure file encryption. When you provide recipient public keys, the export process encrypts the final ZIP archive. Only holders of the corresponding private keys can decrypt it.

Generate keys with:

```bash
# Install age (example for macOS)
brew install age

# Generate a new key pair
age-keygen -o key.txt

# Public key is printed to stdout; share it with exporters
# Private key is saved to key.txt; keep it secret
```

**Redaction presets**

The export pipeline supports configurable scrubbing to remove sensitive data:

- `standard`: Clears acknowledgment/read state, removes file reservations and agent links, scrubs secrets (GitHub tokens, Slack tokens, OpenAI keys, bearer tokens, JWTs) from message bodies and attachment metadata. Retains agent names (which are already meaningless pseudonyms like "BlueMountain"), full message bodies, and attachments.

- `strict`: All standard redactions plus replaces entire message bodies with "[Message body redacted]" placeholder and removes all attachments from the bundle.

All presets apply redaction to message subjects, bodies, and attachment metadata before the bundle is written.

### Static viewer features

The bundled HTML viewer provides:

**Dashboard layout**:
- **Bundle metadata header**: Shows bundle creation time, export settings, and scrubbing preset
- **Summary panels**: Three side-by-side panels displaying projects included, attachment statistics, and redaction summary
- **Message overview**: Searchable list of all messages with filtering by subject/body
- **Raw manifest viewer**: Collapsible JSON display of the complete manifest for verification

**Full-text search**: Powered by SQLite FTS5, runs entirely in the browser. Search syntax supports phrases (`"build plan"`), boolean operators (`plan AND users`), and field filters (`subject:deploy`).

**Markdown rendering**: Message bodies are rendered with GitHub-Flavored Markdown, supporting code blocks, tables, task lists, and inline images.

**OPFS caching**: The SQLite database is cached in Origin Private File System (OPFS) for instant subsequent loads. First load downloads the database, subsequent loads are instant.

**Attachment preview**: Inline images render directly in message bodies. External attachments show file size and download links.

**Message detail view**: Click any message in the list to view its full body, metadata (sender, recipients, timestamp, importance), and attachments.

**No server required**: After the initial HTTP serving (which can be a static file host like S3, GitHub Pages, or Netlify), all functionality runs client-side. No backend, no API calls, no authentication.

### Deployment options

**Option 1: GitHub Pages (automated via wizard)**

```bash
# Use the wizard for fully automated deployment
uv run python -m mcp_agent_mail.cli share wizard
# Select: GitHub Pages → provide repo name → wizard handles everything
```

Or manually:

```bash
# Export and unzip
uv run python -m mcp_agent_mail.cli share export --output ./bundle --no-zip
cd bundle

# Initialize git and push to GitHub
git init
git add .
git commit -m "Initial export"
git remote add origin git@github.com:yourorg/project-archive.git
git push -u origin main

# Enable GitHub Pages in repo settings (source: main branch, root directory)
```

**Option 2: Cloudflare Pages (automated via wizard)**

```bash
# Use the wizard for instant global CDN deployment
uv run python -m mcp_agent_mail.cli share wizard
# Select: Cloudflare Pages → provide project name → wizard deploys directly
```

Or manually with wrangler CLI:

```bash
# Export and deploy
uv run python -m mcp_agent_mail.cli share export --output ./bundle --no-zip
npx wrangler pages deploy ./bundle --project-name=project-archive

# Your site is live at: https://project-archive.pages.dev
```

**Benefits of Cloudflare Pages:**
- Instant deployment (no git repo required)
- Global CDN with 275+ locations
- Automatic HTTPS and DDoS protection
- Zero-downtime updates
- Generous free tier (500 builds/month, unlimited requests)

**Option 3: S3 + CloudFront**

```bash
# Export and unzip
uv run python -m mcp_agent_mail.cli share export --output ./bundle --no-zip

# Upload to S3
aws s3 sync ./bundle s3://your-bucket/archives/project-2024/ --acl public-read

# Access via CloudFront
# https://d123abc.cloudfront.net/archives/project-2024/
```

**Option 4: Nginx static site**

```nginx
server {
  listen 443 ssl;
  server_name archives.example.com;

  ssl_certificate /etc/letsencrypt/live/archives.example.com/fullchain.pem;
  ssl_certificate_key /etc/letsencrypt/live/archives.example.com/privkey.pem;

  root /var/www/archives/project-2024;
  index index.html;

  # Enable gzip for efficient transfer
  gzip on;
  gzip_types text/html text/css application/javascript application/json application/wasm;

  # Cache static assets
  location ~* \.(js|css|wasm|png|jpg|webp)$ {
    expires 1y;
    add_header Cache-Control "public, immutable";
  }

  # CSP headers are already in index.html meta tag
  # Add HTTPS-only and frame protection
  add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
  add_header X-Frame-Options "DENY" always;
  add_header X-Content-Type-Options "nosniff" always;
}
```

**Option 5: Encrypted distribution via file sharing**

For confidential archives:

```bash
# Export with age encryption
uv run python -m mcp_agent_mail.cli share export \
  --output ./bundle \
  --signing-key ./signing.key \
  --age-recipient age1auditor... \
  --age-recipient age1manager...

# This produces bundle.zip.age
# Upload to Dropbox, Google Drive, or send via secure file transfer

# Recipients decrypt locally
uv run python -m mcp_agent_mail.cli share decrypt bundle.zip.age \
  --identity ~/.age/key.txt

# Verify integrity
unzip bundle.zip
uv run python -m mcp_agent_mail.cli share verify ./bundle

# Preview locally
uv run python -m mcp_agent_mail.cli share preview ./bundle
```

### Example workflows

**Quarterly audit package**

```bash
# Export Q4 2024 communications for audit
uv run python -m mcp_agent_mail.cli share export \
  --output ./audit-q4-2024 \
  --scrub-preset strict \
  --signing-key ./audit-signing.key \
  --signing-public-out ./audit-signing.pub \
  --age-recipient age1auditor@firm.example

# Produces: audit-q4-2024.zip.age
# Send to auditor with audit-signing.pub

# Auditor verifies:
age -d -i auditor-key.txt audit-q4-2024.zip.age > audit-q4-2024.zip
unzip audit-q4-2024.zip
python -m mcp_agent_mail.cli share verify ./audit-q4-2024 \
  --public-key $(cat audit-signing.pub)
```

**Executive summary for stakeholders**

```bash
# Export high-importance threads only
# (filter in UI after export, or use SQL to create filtered snapshot)
uv run python -m mcp_agent_mail.cli share export \
  --output ./exec-summary \
  --project backend-prod \
  --scrub-preset standard

# Host on internal web server
cp -r ./exec-summary /var/www/exec-archives/2024-12/
# Share link: https://internal.example.com/exec-archives/2024-12/
```

**Disaster recovery backup**

```bash
# Monthly encrypted backup
uv run python -m mcp_agent_mail.cli share export \
  --output ./backup-$(date +%Y-%m) \
  --scrub-preset none \
  --signing-key ./dr-signing.key \
  --age-recipient age1dr@company.example

# Store in off-site backup system
aws s3 cp backup-2024-12.zip.age s3://dr-backups/mcp-mail/ \
  --storage-class GLACIER_IR

# Restore procedure documented in runbook
```

### Troubleshooting exports

**Export fails with "Database locked"**

The export takes a snapshot using SQLite's Online Backup API. If the server is actively writing, wait a few seconds and retry. For large databases, consider temporarily stopping the server during export.

**Bundle size is too large**

Use `--detach-threshold` to mark large attachments as external references. These won't be included in the bundle but will show file metadata in the viewer.

```bash
# Bundle files under 1MB, mark larger files as external
uv run python -m mcp_agent_mail.cli share export \
  --output ./bundle \
  --detach-threshold 1048576
```

Alternatively, filter to specific projects with `--project`.

**Encrypted bundle won't decrypt**

Verify you're using the correct identity file:

```bash
# Get your public key from your identity file
age-keygen -y identity.txt

# Ensure this public key was included in the --age-recipient values during export
# If you have multiple identity files, try each one
age -d -i identity.txt bundle.zip.age > bundle.zip
```

**Signature verification fails**

Signature verification requires:
1. The original `manifest.json` (unmodified)
2. The `manifest.sig.json` file (contains signature and public key)
3. All assets referenced in the manifest with matching SHA-256 hashes

If verification fails, the bundle may have been tampered with or corrupted during transfer. Re-export and re-transfer.

**Viewer shows blank page or errors**

Check browser console for errors. Common issues:

- **OPFS not supported**: Older browsers may not support Origin Private File System. The viewer will fall back to in-memory mode (slower).
- **Database too large**: Browsers limit in-memory database size to ~1-2GB. Use chunking (`--chunk-threshold`) for very large archives.
- **CSP violations**: If hosting the bundle, ensure the web server doesn't add conflicting CSP headers. The viewer's CSP is defined in `index.html` and should not be overridden.

### On-disk layout (per project)

```
<store>/projects/<slug>/
  agents/<AgentName>/profile.json
  agents/<AgentName>/inbox/YYYY/MM/<msg-id>.md
  agents/<AgentName>/outbox/YYYY/MM/<msg-id>.md
  messages/YYYY/MM/<msg-id>.md
  messages/threads/<thread-id>.md  # optional human digest maintained by the server
  file_reservations/<sha1-of-path>.json
  attachments/<xx>/<sha1>.webp
```

### Message file format

Messages are GitHub-Flavored Markdown with JSON frontmatter (fenced by `---json`). Attachments are either WebP files referenced by relative path or inline base64 WebP data URIs.

```markdown
---json
{
  "id": 1234,
  "thread_id": "TKT-123",
  "project": "/abs/path/backend",
  "project_slug": "backend-abc123",
  "from": "GreenCastle",
  "to": ["BlueLake"],
  "cc": [],
  "created": "2025-10-23T15:22:14Z",
  "importance": "high",
  "ack_required": true,
  "attachments": [
    {"type": "file", "media_type": "image/webp", "path": "projects/backend-abc123/attachments/2a/2a6f.../diagram.webp"}
  ]
}
---

# Build plan for /api/users routes

... body markdown ...
```

### Data model (SQLite)

- `projects(id, human_key, slug, created_at)`
- `agents(id, project_id, name, program, model, task_description, inception_ts, last_active_ts, attachments_policy, contact_policy)`
- `messages(id, project_id, sender_id, thread_id, subject, body_md, created_ts, importance, ack_required, attachments)`
- `message_recipients(message_id, agent_id, kind, read_ts, ack_ts)`
- `file_reservations(id, project_id, agent_id, path_pattern, exclusive, reason, created_ts, expires_ts, released_ts)`
- `agent_links(id, a_project_id, a_agent_id, b_project_id, b_agent_id, status, reason, created_ts, updated_ts, expires_ts)`
- `project_sibling_suggestions(id, project_a_id, project_b_id, score, status, rationale, created_ts, evaluated_ts, confirmed_ts, dismissed_ts)`
- `fts_messages(message_id UNINDEXED, subject, body)` + triggers for incremental updates

### Concurrency and lifecycle

- One request/task = one isolated operation
- Archive writes are guarded by a per-project `.archive.lock` under `projects/<slug>/`
- Git index/commit operations are serialized across the shared archive repo by a repo-level `.commit.lock`
- DB operations are short-lived and scoped to each tool call; FTS triggers keep the search index current
- Artifacts are written first, then committed as a cohesive unit with a descriptive message
- Attachments are content-addressed (sha1) to avoid duplication

## How it works (key flows)

1) Create an identity

- `register_agent(project_key, program, model, name?, task_description?)` → creates/updates a named identity, persists profile to Git, and commits.

2) Send a message

- `send_message(project_key, sender_name, to[], subject, body_md, cc?, bcc?, attachment_paths?, convert_images?, importance?, ack_required?, thread_id?, auto_contact_if_blocked?)`
- Writes a canonical message under `messages/YYYY/MM/`, an outbox copy for the sender, and inbox copies for each recipient; commits all artifacts.
- Optionally converts images (local paths or data URIs) to WebP and embeds small ones inline.

```mermaid
sequenceDiagram
  participant Agent
  participant Server
  participant DB
  participant Git

  Agent->>Server: call send_message
  Server->>DB: insert message and recipients
  DB-->>Server: ok
  Server->>Git: write canonical markdown
  Server->>Git: write outbox copy
  Server->>Git: write inbox copies
  Server->>Git: commit
  Server-->>Agent: result
```

3) Check inbox

- `fetch_inbox(project_key, agent_name, since_ts?, urgent_only?, include_bodies?, limit?)` returns recent messages, preserving thread_id where available.
- `acknowledge_message(project_key, agent_name, message_id)` marks acknowledgements.

4) Avoid conflicts with file reservations (leases)

- `file_reservation_paths(project_key, agent_name, paths[], ttl_seconds, exclusive, reason)` records an advisory lease in DB and writes JSON reservation artifacts in Git; conflicts are reported if overlapping active exclusives exist (reservations are still granted; conflicts are returned alongside grants).
- `release_file_reservations(project_key, agent_name, paths? | file_reservation_ids?)` releases active leases (all if none specified). JSON artifacts remain for audit history.
- Optional: install a pre-commit hook in your code repo that blocks commits conflicting with other agents' active exclusive file reservations.

```mermaid
sequenceDiagram
  participant Agent
  participant Server
  participant DB
  participant Git

  Agent->>Server: call file_reservation_paths
  Server->>DB: expire old leases and check overlaps
  DB-->>Server: conflicts or grants
  Server->>DB: insert file reservation rows
  Server->>Git: write file reservation JSON files
  Server->>Git: commit
  Server-->>Agent: granted paths and any conflicts
```

5) Search & summarize

- `search_messages(project_key, query, limit?)` uses FTS5 over subject and body.
- `summarize_thread(project_key, thread_id, include_examples?)` extracts key points, actions, and participants from the thread.
- `reply_message(project_key, message_id, sender_name, body_md, ...)` creates a subject-prefixed reply, preserving or creating a thread.

### Semantics & invariants

- Identity
  - Names can be any sanitized alphanumeric string and are globally unique; if you omit `name` (or it conflicts), the server generates an adjective+noun codename, and any `name_hint` is sanitized (alnum) before use
  - Reusing a name automatically retires the previous identity (history stays readable) so you can reclaim favorite handles without manual cleanup
  - `whois` returns the stored profile; `list_agents` can filter by recent activity
  - `last_active_ts` is bumped on relevant interactions (messages, inbox checks, etc.)
- Threads
  - Replies inherit `thread_id` from the original; if missing, the reply sets `thread_id` to the original message id
  - Subject lines are prefixed (e.g., `Re:`) for readability in mailboxes
- Attachments
  - Image references (file path or data URI) are converted to WebP; small images embed inline when policy allows
  - Non-absolute paths resolve relative to the project repo root
  - Stored under `attachments/<xx>/<sha1>.webp` and referenced by relative path in frontmatter
- File Reservations
  - TTL-based; exclusive means "please don't modify overlapping surfaces" for others until expiry or release
  - Conflict detection is per exact path pattern; shared reservations can coexist, exclusive conflicts are surfaced
  - JSON artifacts remain in Git for audit even after release (DB tracks release_ts)
- Search
  - External-content FTS virtual table and triggers index subject/body on insert/update/delete
  - Queries are constrained to the project id and ordered by `created_ts DESC`

## Contact model and "consent-lite" messaging

Goal: make coordination "just work" without spam across unrelated agents. The server enforces per-project isolation by default and adds an optional consent layer within a project so agents only contact relevant peers.

### Isolation by project

- All tools require a `project_key`. Agents only see messages addressed to them within that project.
- An agent working in Project A is invisible to agents in Project B unless explicit cross-project contact is established (see below). This avoids distraction between unrelated repositories.

### Policies (per agent) - OPTIONAL / NOT ENFORCED

**NOTE: Contact policies are no longer enforced. All agents can send messages to each other directly without contact approval.**

The following policy settings are maintained for backward compatibility but have no effect:

- `open`: accept any targeted messages in the project.
- `auto` (default): allow messages when there is obvious shared context.
- `contacts_only`: require an approved contact link first.
- `block_all`: reject all new contacts.

Use `set_contact_policy(project_key, agent_name, policy)` to update (optional).

### Request/approve contact - OPTIONAL / NOT REQUIRED

**NOTE: Contact approval is no longer required to send messages. Use `send_message` directly.**

The following tools are maintained for backward compatibility and optional contact tracking:

- `request_contact(project_key, from_agent, to_agent, reason?, ttl_seconds?)` creates or refreshes a pending link and sends a small ack_required "intro" message to the recipient.
- `respond_contact(project_key, to_agent, from_agent, accept, ttl_seconds?)` approves or denies; approval grants messaging until expiry.
- `list_contacts(project_key, agent_name)` surfaces current links.

### Cross-project coordination (frontend vs backend repos)

When two repos represent the same underlying project (e.g., `frontend` and `backend`), you have two options:

1) Use the same `project_key` across both workspaces. Agents in both repos operate under one project namespace and benefit from full inbox/outbox coordination automatically.

2) Keep separate `project_key`s. Agents can message each other across projects directly using `send_message` with the `project:<slug>#<AgentName>` addressing format.

**NOTE:** Contact approval is no longer required for cross-project messaging. Contact enforcement has been removed to enable frictionless collaboration between agents.

<!-- Consolidated in API Quick Reference → Tools below to avoid duplication -->

## Resource layer (read-only URIs)

Expose common reads as resources that clients can fetch. See API Quick Reference → Resources for the full list and parameters.

Example (conceptual) resource read:

```json
{
  "method": "resources/read",
  "params": {"uri": "resource://inbox/BlueLake?project=/abs/path/backend&limit=20"}
}
```

<!-- Parameters consolidated in API Quick Reference → Resources -->

```mermaid
sequenceDiagram
  participant Client
  participant Server
  participant DB

  Client->>Server: read inbox resource
  Server->>DB: select messages for agent
  DB-->>Server: rows
  Server-->>Client: inbox data
```

<!-- View URIs consolidated in API Quick Reference → Resources -->

## File Reservations and the optional pre-commit guard

Exclusive file reservations are advisory but visible and auditable:

- A reservation JSON is written to `file_reservations/<sha1(path)>.json` capturing holder, pattern, exclusivity, created/expires
- The pre-commit guard scans active exclusive reservations and blocks commits that touch conflicting paths held by another agent
- Agents must set `AGENT_NAME` so the guard knows who "owns" the commit
- The server continuously evaluates reservations for staleness (agent inactivity + mail/filesystem/git silence) and releases abandoned locks automatically; the `force_release_file_reservation` tool uses the same heuristics and notifies the previous holder when another agent clears a stale lease

Install the guard into a code repo (conceptual tool call):

```json
{
  "method": "tools/call",
  "params": {
    "name": "install_precommit_guard",
    "arguments": {
      "project_key": "/abs/path/backend",
      "code_repo_path": "/abs/path/backend"
    }
  }
}
```

## Configuration

Configuration is loaded from an existing `.env` via `python-decouple`. Do not use `os.getenv` or auto-dotenv loaders.

### Changing the HTTP Port

If port 8765 is already in use (e.g., by Cursor's Python extension), you can change it:

**Option 1: During installation**
```bash
# One-liner with custom port
curl -fsSL https://raw.githubusercontent.com/Dicklesworthstone/mcp_agent_mail/main/scripts/install.sh | bash -s -- --port 9000 --yes

# Or with local script
./scripts/install.sh --port 9000 --yes
```

**Option 2: After installation (CLI)**
```bash
# Change port using CLI command
uv run python -m mcp_agent_mail.cli config set-port 9000

# View current port configuration
uv run python -m mcp_agent_mail.cli config show-port

# Restart server for changes to take effect
scripts/run_server_with_token.sh
```

**Option 3: Manual .env edit**
```bash
# Edit .env file manually with your text editor (recommended)
nano .env  # or vim, code, etc.

# Or append (⚠️ warning: will create duplicate if HTTP_PORT already exists)
echo "HTTP_PORT=9000" >> .env
```

**Option 4: CLI server override**
```bash
# Override port at server startup (doesn't modify .env)
uv run python -m mcp_agent_mail.cli serve-http --port 9000
```

```python
from decouple import Config as DecoupleConfig, RepositoryEnv

decouple_config = DecoupleConfig(RepositoryEnv(".env"))

STORAGE_ROOT = decouple_config("STORAGE_ROOT", default="~/.mcp_agent_mail_git_mailbox_repo")
HTTP_HOST = decouple_config("HTTP_HOST", default="127.0.0.1")
HTTP_PORT = int(decouple_config("HTTP_PORT", default=8765))
HTTP_PATH = decouple_config("HTTP_PATH", default="/mcp/")
```

Common variables you may set:

### Tool Exposure Modes (Lazy Loading)

The server supports two tool exposure modes to manage token usage:

#### Core Mode (Default)
- Exposes 10 essential tools: `health_check`, `ensure_project`, `register_agent`, `whois`, `send_message`, `reply_message`, `fetch_inbox`, `mark_message_read`, `list_extended_tools`, `call_extended_tool`
- ~10k tokens initial context
- Extended tools (19 additional tools) remain accessible via the `call_extended_tool` meta-tool
- Best for most use cases where you want to minimize initial context usage

#### Extended Mode
- Exposes all 29 tools directly to the MCP client
- ~25k tokens initial context
- No need to use meta-tools; all tools are available directly
- Best for workflows that heavily use many advanced features

#### Switching modes

```bash
# Set to extended mode (expose all tools)
echo "MCP_TOOLS_MODE=extended" >> .env

# Set to core mode (lazy loading, default)
echo "MCP_TOOLS_MODE=core" >> .env
# Or simply remove the line (core is now the default)

# Restart server for changes to take effect
scripts/run_server_with_token.sh
```

#### Using extended tools in core mode

```python
# Instead of calling the tool directly:
await client.call_tool("acknowledge_message", {"project_key": "...", "agent_name": "...", "message_id": 123})

# Use the meta-tool in core mode:
await client.call_tool("call_extended_tool", {
    "tool_name": "acknowledge_message",
    "arguments": {"project_key": "...", "agent_name": "...", "message_id": 123}
})

# List all extended tools:
result = await client.call_tool("list_extended_tools", {})
# Returns: {"total": 19, "by_category": {...}, "tools": [{name, category, description}, ...]}
```


### Configuration reference

| Name | Default | Description |
| :-- | :-- | :-- |
| `STORAGE_ROOT` | `~/.mcp_agent_mail_git_mailbox_repo` | Root for per-project repos and SQLite DB |
| `HTTP_HOST` | `127.0.0.1` | Bind host for HTTP transport |
| `HTTP_PORT` | `8765` | Bind port for HTTP transport |
| `HTTP_PATH` | `/mcp/` | HTTP path where MCP endpoint is mounted |
| `HTTP_JWT_ENABLED` | `false` | Enable JWT validation middleware |
| `HTTP_JWT_SECRET` |  | HMAC secret for HS* algorithms (dev) |
| `HTTP_JWT_JWKS_URL` |  | JWKS URL for public key verification |
| `HTTP_JWT_ALGORITHMS` | `HS256` | CSV of allowed algs |
| `HTTP_JWT_AUDIENCE` |  | Expected `aud` (optional) |
| `HTTP_JWT_ISSUER` |  | Expected `iss` (optional) |
| `HTTP_JWT_ROLE_CLAIM` | `role` | JWT claim name containing role(s) |
| `HTTP_RBAC_ENABLED` | `true` | Enforce read-only vs tools RBAC |
| `HTTP_RBAC_READER_ROLES` | `reader,read,ro` | CSV of reader roles |
| `HTTP_RBAC_WRITER_ROLES` | `writer,write,tools,rw` | CSV of writer roles |
| `HTTP_RBAC_DEFAULT_ROLE` | `reader` | Role used when none present |
| `HTTP_RBAC_READONLY_TOOLS` | `health_check,fetch_inbox,whois,search_messages,summarize_thread,summarize_threads` | CSV of read-only tool names |
| `HTTP_RATE_LIMIT_ENABLED` | `false` | Enable token-bucket limiter |
| `HTTP_RATE_LIMIT_BACKEND` | `memory` | `memory` or `redis` |
| `HTTP_RATE_LIMIT_PER_MINUTE` | `60` | Legacy per-IP limit (fallback) |
| `HTTP_RATE_LIMIT_TOOLS_PER_MINUTE` | `60` | Per-minute for tools/call |
| `HTTP_RATE_LIMIT_TOOLS_BURST` | `0` | Optional burst for tools (0=auto=rpm) |
| `HTTP_RATE_LIMIT_RESOURCES_PER_MINUTE` | `120` | Per-minute for resources/read |
| `HTTP_RATE_LIMIT_RESOURCES_BURST` | `0` | Optional burst for resources (0=auto=rpm) |
| `HTTP_RATE_LIMIT_REDIS_URL` |  | Redis URL for multi-worker limits |
| `HTTP_REQUEST_LOG_ENABLED` | `false` | Print request logs (Rich + JSON) |
| `LOG_JSON_ENABLED` | `false` | Output structlog JSON logs |
| `INLINE_IMAGE_MAX_BYTES` | `65536` | Threshold (bytes) for inlining WebP images during send_message |
| `CONVERT_IMAGES` | `true` | Convert images to WebP (and optionally inline small ones) |
| `KEEP_ORIGINAL_IMAGES` | `false` | Also store original image bytes alongside WebP (attachments/originals/) |
| `LOG_LEVEL` | `INFO` | Server log level |
| `HTTP_CORS_ENABLED` | `false` | Enable CORS middleware when true |
| `HTTP_CORS_ORIGINS` |  | CSV of allowed origins (e.g., `https://app.example.com,https://ops.example.com`) |
| `HTTP_CORS_ALLOW_CREDENTIALS` | `false` | Allow credentials on CORS |
| `HTTP_CORS_ALLOW_METHODS` | `*` | CSV of allowed methods or `*` |
| `HTTP_CORS_ALLOW_HEADERS` | `*` | CSV of allowed headers or `*` |
| `HTTP_BEARER_TOKEN` |  | Static bearer token (only when JWT disabled) |
| `HTTP_ALLOW_LOCALHOST_UNAUTHENTICATED` | `true` | Allow localhost requests without auth (dev convenience) |
| `HTTP_OTEL_ENABLED` | `false` | Enable OpenTelemetry instrumentation |
| `OTEL_SERVICE_NAME` | `mcp-agent-mail` | Service name for telemetry |
| `OTEL_EXPORTER_OTLP_ENDPOINT` |  | OTLP exporter endpoint URL |
| `APP_ENVIRONMENT` | `development` | Environment name (development/production) |
| `DATABASE_URL` | `sqlite+aiosqlite:///./storage.sqlite3` | SQLAlchemy async database URL |
| `DATABASE_ECHO` | `false` | Echo SQL statements for debugging |
| `GIT_AUTHOR_NAME` | `mcp-agent` | Git commit author name |
| `GIT_AUTHOR_EMAIL` | `mcp-agent@example.com` | Git commit author email |
| `LLM_ENABLED` | `true` | Enable LiteLLM for thread summaries and discovery |
| `LLM_DEFAULT_MODEL` | `gpt-5-mini` | Default LiteLLM model identifier |
| `LLM_TEMPERATURE` | `0.2` | LLM temperature for text generation |
| `LLM_MAX_TOKENS` | `512` | Max tokens for LLM completions |
| `LLM_CACHE_ENABLED` | `true` | Enable LLM response caching |
| `LLM_CACHE_BACKEND` | `memory` | LLM cache backend (`memory` or `redis`) |
| `LLM_CACHE_REDIS_URL` |  | Redis URL for LLM cache (if backend=redis) |
| `LLM_COST_LOGGING_ENABLED` | `true` | Log LLM API costs and token usage |
| `FILE_RESERVATIONS_CLEANUP_ENABLED` | `false` | Enable background cleanup of expired file reservations |
| `FILE_RESERVATIONS_CLEANUP_INTERVAL_SECONDS` | `60` | Interval for file reservations cleanup task |
| `FILE_RESERVATION_INACTIVITY_SECONDS` | `1800` | Inactivity threshold (seconds) before a reservation is considered stale |
| `FILE_RESERVATION_ACTIVITY_GRACE_SECONDS` | `900` | Grace window for recent mail/filesystem/git activity to keep a reservation active |
| `FILE_RESERVATIONS_ENFORCEMENT_ENABLED` | `true` | Block message writes on conflicting file reservations |
| `ACK_TTL_ENABLED` | `false` | Enable overdue ACK scanning (logs/panels; see views/resources) |
| `ACK_TTL_SECONDS` | `1800` | Age threshold (seconds) for overdue ACKs |
| `ACK_TTL_SCAN_INTERVAL_SECONDS` | `60` | Scan interval for overdue ACKs |
| `ACK_ESCALATION_ENABLED` | `false` | Enable escalation for overdue ACKs |
| `ACK_ESCALATION_MODE` | `log` | `log` or `file_reservation` escalation mode |
| `ACK_ESCALATION_CLAIM_TTL_SECONDS` | `3600` | TTL for escalation file reservations |
| `ACK_ESCALATION_CLAIM_EXCLUSIVE` | `false` | Make escalation file reservation exclusive |
| `ACK_ESCALATION_CLAIM_HOLDER_NAME` |  | Ops agent name to own escalation file reservations |
| `CONTACT_ENFORCEMENT_ENABLED` | `false` | (Deprecated - enforcement removed) |
| `CONTACT_AUTO_TTL_SECONDS` | `86400` | TTL for auto-approved contacts (1 day) |
| `CONTACT_AUTO_RETRY_ENABLED` | `true` | Auto-retry contact requests on policy violations |
| `MESSAGING_AUTO_REGISTER_RECIPIENTS` | `true` | Automatically create missing local recipients during `send_message` and retry routing |
| `MESSAGING_AUTO_HANDSHAKE_ON_BLOCK` | `true` | When contact policy blocks delivery, attempt a contact handshake (auto-accept) and retry |
| `TOOLS_LOG_ENABLED` | `true` | Log tool invocations for debugging |
| `LOG_RICH_ENABLED` | `true` | Enable Rich console logging |
| `LOG_INCLUDE_TRACE` | `false` | Include trace-level logs |
| `TOOL_METRICS_EMIT_ENABLED` | `false` | Emit periodic tool usage metrics |
| `TOOL_METRICS_EMIT_INTERVAL_SECONDS` | `60` | Interval for metrics emission |
| `RETENTION_REPORT_ENABLED` | `false` | Enable retention/quota reporting |
| `RETENTION_REPORT_INTERVAL_SECONDS` | `3600` | Interval for retention reports (1 hour) |
| `RETENTION_MAX_AGE_DAYS` | `180` | Max age for retention policy reporting |
| `QUOTA_ENABLED` | `false` | Enable quota enforcement |
| `QUOTA_ATTACHMENTS_LIMIT_BYTES` | `0` | Max attachment storage per project (0=unlimited) |
| `QUOTA_INBOX_LIMIT_COUNT` | `0` | Max inbox messages per agent (0=unlimited) |
| `RETENTION_IGNORE_PROJECT_PATTERNS` | `demo,test*,testproj*,testproject,backendproj*,frontendproj*` | CSV of project patterns to ignore in retention/quota reports |
| `AGENT_NAME_ENFORCEMENT_MODE` | `coerce` | Agent naming policy: `strict` (reject invalid/taken sanitized names), `coerce` (auto-generate when invalid or taken), `always_auto` (always auto-generate) |
| `MCP_TOOLS_MODE` | `core` | Tool exposure mode: `core` (10 essential tools + meta-tools for lazy loading ~10k tokens) or `extended` (all 29 tools exposed directly ~25k tokens). Core mode reduces initial context by exposing only essential coordination tools, with extended tools accessible via `call_extended_tool` meta-tool. |

## Development quick start

Prerequisite: complete the setup above (Python 3.14 + uv venv + uv sync).

Dev helpers:

```bash
# Quick endpoint smoke test (server must be running locally)
bash scripts/test_endpoints.sh

# Pre-commit guard smoke test (no pytest)
bash scripts/test_guard.sh
```

Database schema (automatic):

```bash
# Tables are created from SQLModel definitions on first run.
# If models change, delete the SQLite DB (and WAL/SHM) and run migrate again.
uv run python -m mcp_agent_mail.cli migrate
```

Run the server (HTTP-only). Use the Typer CLI or module entry:

```bash
uv run python -m mcp_agent_mail.cli serve-http
uv run python -m mcp_agent_mail.http --host 127.0.0.1 --port 8765
```

Connect with your MCP client using the HTTP (Streamable HTTP) transport on the configured host/port. The endpoint tolerates both `/mcp` and `/mcp/`.

## Search syntax tips (SQLite FTS5)

- Basic terms: `plan users`
- Phrase search: `"build plan"`
- Prefix search: `mig*`
- Boolean operators: `plan AND users NOT legacy`
- Field boosting is not enabled by default; subject and body are indexed. Keep queries concise. When FTS is unavailable, the UI/API automatically falls back to SQL LIKE on subject/body.

## Design choices and rationale

- **HTTP-only FastMCP**: Streamable HTTP is the modern remote transport; STDIO is not exposed here by design
- **Git + Markdown**: Human-auditable, diffable artifacts that fit developer workflows (inbox/outbox mental model)
- **SQLite + FTS5**: Efficient indexing/search with minimal ops footprint
- **Advisory file reservations**: Make intent explicit and reviewable; optional guard enforces reservations at commit time
- **WebP attachments**: Compact images by default; inline embedding keeps small diagrams in context
  - Optional: keep original binaries and dedup manifest under `attachments/` for audit and reuse

## Examples (conceptual tool calls)

This section has been removed to keep the README focused. See API Quick Reference below for canonical method signatures.

## Operational notes

- One async session per request/task; don't share across concurrent coroutines
- Use explicit loads in async code; avoid implicit lazy loads
- Use async-friendly file operations when needed; Git operations are serialized with a file lock
- Clean shutdown should dispose any async engines/resources (if introduced later)

## Security and ops

- Transport
  - HTTP-only (Streamable HTTP). Place behind a reverse proxy (e.g., NGINX) with TLS termination for production
- Auth
  - Optional JWT (HS*/JWKS) via HTTP middleware; enable with `HTTP_JWT_ENABLED=true`
  - Static bearer token (`HTTP_BEARER_TOKEN`) is independent of JWT; when set, BearerAuth protects all routes (including UI). You may use it alone or together with JWT.
  - When JWKS is configured (`HTTP_JWT_JWKS_URL`), incoming JWTs must include a matching `kid` header; tokens without `kid` or with unknown `kid` are rejected
  - Starter RBAC (reader vs writer) using role configuration; see `HTTP_RBAC_*` settings
- Reverse proxy + TLS (minimal example)
  - NGINX location block:
    ```nginx
    upstream mcp_mail { server 127.0.0.1:8765; }
    server {
      listen 443 ssl;
      server_name mcp.example.com;
      ssl_certificate /etc/letsencrypt/live/mcp.example.com/fullchain.pem;
      ssl_certificate_key /etc/letsencrypt/live/mcp.example.com/privkey.pem;
      location /mcp/ { proxy_pass http://mcp_mail; proxy_set_header Host $host; proxy_set_header X-Forwarded-Proto https; }
    }
    ```
- Backups and retention
  - The Git repos and SQLite DB live under `STORAGE_ROOT`; back them up together for consistency
- Observability
  - Add logging and metrics at the ASGI layer returned by `mcp.http_app()` (Prometheus, OpenTelemetry)
- Concurrency
  - Archive writes: per-project `.archive.lock` prevents cross-project head-of-line blocking
  - Commits: repo-level `.commit.lock` serializes Git index/commit to avoid races across projects

## Python client example (HTTP JSON-RPC)

This section has been removed to keep the README focused. Client code samples belong in `examples/`.

## Troubleshooting

- "sender_name not registered"
  - Create the agent first with `register_agent` or `create_agent_identity`, or check the `project_key` you're using matches the sender's project
- Pre-commit hook blocks commits
  - Set `AGENT_NAME` to your agent identity; release or wait for conflicting exclusive file reservations; inspect `.git/hooks/pre-commit`
- Inline images didn't embed
  - Ensure `convert_images=true`; images are automatically inlined if the compressed WebP size is below the server's `INLINE_IMAGE_MAX_BYTES` threshold (default 64KB). Larger images are stored as attachments instead.
- Message not found
  - Confirm the `project` disambiguation when using `resource://message/{id}`; ids are unique per project
- Inbox empty but messages exist
  - Check `since_ts`, `urgent_only`, and `limit`; verify recipient names match exactly (case-sensitive)

## FAQ

- Why Git and SQLite together?
  - Git provides human-auditable artifacts and history; SQLite provides fast queries and FTS search. Each is great at what the other isn't.
- Are file reservations enforced?
  - Yes, optionally. The server can block message writes when a conflicting active exclusive reservation exists (`FILE_RESERVATIONS_ENFORCEMENT_ENABLED=true`, default). Reservations themselves are advisory and always return both `granted` and `conflicts`. The optional pre-commit hook adds local enforcement at commit time in your code repo.
- Why HTTP-only?
  - Streamable HTTP is the modern remote transport for MCP; avoiding extra transports reduces complexity and encourages a uniform integration path.

- Why JSON-RPC instead of REST or gRPC?
  - MCP defines a tool/resource method call model that maps naturally to JSON-RPC over a single endpoint. It keeps clients simple (one URL, method name + params), plays well with proxies, and avoids SDK lock-in while remaining language-agnostic.

- Why separate "resources" (reads) from "tools" (mutations)?
  - Clear semantics enable aggressive caching and safe prefetch for resources, while tools remain explicit, auditable mutations. This split also powers RBAC (read-only vs writer) without guesswork.

- Why canonical message storage in Git, not only in the database?
  - Git gives durable, diffable, human-reviewable artifacts you can clone, branch, and audit. SQLite provides fast indexing and FTS. The combo preserves governance and operability without a heavyweight message bus.

- Why advisory file reservations instead of global locks?
  - Agents coordinate asynchronously; hard locks create head-of-line blocking and brittle failures. Advisory reservations surface intent and conflicts while the optional pre-commit guard enforces locally where it matters.

- Why do auto-generated names look like adjective+noun combos?
  - When you skip `name` (or it conflicts), the server falls back to a curated adjective/noun pool to create memorable codenames. You're still free to supply any sanitized alphanumeric name if you want a custom identity.

- Why is `project_key` an absolute path?
  - Using the workspace's absolute path creates a stable, collision-resistant project identity across shells and agents. Slugs are derived deterministically from it, avoiding accidental forks of the same project.

- Why WebP attachments and optional inlining?
  - WebP provides compact, high-quality images. Small images can be inlined for readability; larger ones are stored as attachments. You can keep originals when needed (`KEEP_ORIGINAL_IMAGES=true`).

- Why both static bearer and JWT/JWKS support?
  - Local development should be zero-friction (single bearer). Production benefits from verifiable JWTs with role claims, rotating keys via JWKS, and layered RBAC.

- Why SQLite FTS5 instead of an external search service?
  - FTS5 delivers fast, relevant search with minimal ops. It’s embedded, portable, and easy to back up with the Git archive. If FTS isn’t available, we degrade to SQL LIKE automatically.

- Why is LLM usage optional?
  - Summaries and discovery should enhance, not gate, core functionality. Keeping LLM usage optional controls cost and latency while allowing richer UX when enabled.

## API Quick Reference

### Tools

> Tip: to see tools grouped by workflow with recommended playbooks, fetch `resource://tooling/directory`.

| Name | Signature | Returns | Notes |
| :-- | :-- | :-- | :-- |
| `health_check` | `health_check()` | `{status, environment, http_host, http_port, database_url}` | Lightweight readiness probe |
| `ensure_project` | `ensure_project(human_key: str)` | `{id, slug, human_key, created_at}` | Idempotently creates/ensures project |
| `register_agent` | `register_agent(project_key: str, program: str, model: str, name?: str, task_description?: str, attachments_policy?: str)` | Agent profile dict | Creates/updates agent; writes profile to Git |
| `whois` | `whois(project_key: str, agent_name: str, include_recent_commits?: bool, commit_limit?: int)` | Agent profile dict | Enriched profile for one agent (optionally includes recent commits) |
| `create_agent_identity` | `create_agent_identity(project_key: str, program: str, model: str, name_hint?: str, task_description?: str, attachments_policy?: str)` | Agent profile dict | Always creates a new unique agent |
| `send_message` | `send_message(project_key: str, sender_name: str, to: list[str], subject: str, body_md: str, cc?: list[str], bcc?: list[str], attachment_paths?: list[str], convert_images?: bool, importance?: str, ack_required?: bool, thread_id?: str, auto_contact_if_blocked?: bool)` | `{deliveries: list, count: int, attachments?}` | Writes canonical + inbox/outbox, converts images |
| `reply_message` | `reply_message(project_key: str, message_id: int, sender_name: str, body_md: str, to?: list[str], cc?: list[str], bcc?: list[str], subject_prefix?: str)` | `{thread_id, reply_to, deliveries: list, count: int, attachments?}` | Preserves/creates thread, inherits flags |
| `request_contact` | `request_contact(project_key: str, from_agent: str, to_agent: str, to_project?: str, reason?: str, ttl_seconds?: int)` | Contact link dict | [OPTIONAL] Request permission to message another agent (no longer required) |
| `respond_contact` | `respond_contact(project_key: str, to_agent: str, from_agent: str, accept: bool, from_project?: str, ttl_seconds?: int)` | Contact link dict | [OPTIONAL] Approve or deny a contact request (no longer required) |
| `list_contacts` | `list_contacts(project_key: str, agent_name: str)` | `list[dict]` | [OPTIONAL] List contact links for an agent |
| `set_contact_policy` | `set_contact_policy(project_key: str, agent_name: str, policy: str)` | Agent dict | [OPTIONAL] Set policy (not enforced) |
| `fetch_inbox` | `fetch_inbox(project_key: str, agent_name: str, limit?: int, urgent_only?: bool, include_bodies?: bool, since_ts?: str)` | `list[dict]` | Non-mutating inbox read |
| `mark_message_read` | `mark_message_read(project_key: str, agent_name: str, message_id: int)` | `{message_id, read, read_at}` | Per-recipient read receipt |
| `acknowledge_message` | `acknowledge_message(project_key: str, agent_name: str, message_id: int)` | `{message_id, acknowledged, acknowledged_at, read_at}` | Sets ack and read |
| `macro_start_session` | `macro_start_session(human_key: str, program: str, model: str, task_description?: str, agent_name?: str, file_reservation_paths?: list[str], file_reservation_reason?: str, file_reservation_ttl_seconds?: int, inbox_limit?: int)` | `{project, agent, file_reservations, inbox}` | Orchestrates ensure→register→optional file reservation→inbox fetch |
| `macro_prepare_thread` | `macro_prepare_thread(project_key: str, thread_id: str, program: str, model: str, agent_name?: str, task_description?: str, register_if_missing?: bool, include_examples?: bool, inbox_limit?: int, include_inbox_bodies?: bool, llm_mode?: bool, llm_model?: str)` | `{project, agent, thread, inbox}` | Bundles registration, thread summary, and inbox context |
| `macro_file_reservation_cycle` | `macro_file_reservation_cycle(project_key: str, agent_name: str, paths: list[str], ttl_seconds?: int, exclusive?: bool, reason?: str, auto_release?: bool)` | `{file_reservations, released}` | File Reservation + optionally release surfaces around a focused edit block |
| `macro_contact_handshake` | `macro_contact_handshake(project_key: str, requester|agent_name: str, target|to_agent: str, to_project?: str, reason?: str, ttl_seconds?: int, auto_accept?: bool, welcome_subject?: str, welcome_body?: str)` | `{request, response, welcome_message}` | [OPTIONAL] Automates contact request/approval (no longer required; use send_message directly) |
| `search_messages` | `search_messages(project_key: str, query: str, limit?: int)` | `list[dict]` | FTS5 search (bm25) |
| `summarize_thread` | `summarize_thread(project_key: str, thread_id: str, include_examples?: bool, llm_mode?: bool, llm_model?: str)` | `{thread_id, summary, examples}` | Extracts participants, key points, actions |
| `summarize_threads` | `summarize_threads(project_key: str, thread_ids: list[str], llm_mode?: bool, llm_model?: str, per_thread_limit?: int)` | `{threads[], aggregate}` | Digest across multiple threads (optional LLM refinement) |
| `install_precommit_guard` | `install_precommit_guard(project_key: str, code_repo_path: str)` | `{hook}` | Install a Git pre-commit guard in a target repo |
| `uninstall_precommit_guard` | `uninstall_precommit_guard(code_repo_path: str)` | `{removed}` | Remove the guard from a repo |
| `file_reservation_paths` | `file_reservation_paths(project_key: str, agent_name: str, paths: list[str], ttl_seconds?: int, exclusive?: bool, reason?: str)` | `{granted: list, conflicts: list}` | Advisory leases; Git artifact per path |
| `release_file_reservations` | `release_file_reservations(project_key: str, agent_name: str, paths?: list[str], file_reservation_ids?: list[int])` | `{released, released_at}` | Releases agent's active file reservations |
| `force_release_file_reservation` | `force_release_file_reservation(project_key: str, agent_name: str, file_reservation_id: int, notify_previous?: bool, note?: str)` | `{released, released_at, reservation}` | Clears stale reservations using inactivity/mail/fs/git heuristics and notifies the previous holder |
| `renew_file_reservations` | `renew_file_reservations(project_key: str, agent_name: str, extend_seconds?: int, paths?: list[str], file_reservation_ids?: list[int])` | `{renewed, file reservations[]}` | Extend TTL of existing file reservations |

### Resources

| URI | Params | Returns | Notes |
| :-- | :-- | :-- | :-- |
| `resource://config/environment` | — | `{environment, database_url, http}` | Inspect server settings |
| `resource://tooling/directory` | — | `{generated_at, metrics_uri, clusters[], playbooks[]}` | Grouped tool directory + workflow playbooks |
| `resource://tooling/schemas` | — | `{tools: {<name>: {required[], optional[], aliases{}}}}` | Argument hints for tools |
| `resource://tooling/metrics` | — | `{generated_at, tools[]}` | Aggregated call/error counts per tool |
| `resource://tooling/locks` | — | `{locks[], summary}` | Active locks and owners (debug only). Categories: `archive` (per-project `.archive.lock`) and `custom` (e.g., repo `.commit.lock`). |
| `resource://tooling/capabilities/{agent}{?project}` | listed| `{generated_at, agent, project, capabilities[]}` | Capabilities assigned to the agent (see `deploy/capabilities/agent_capabilities.json`) |
| `resource://tooling/recent/{window_seconds}{?agent,project}` | listed | `{generated_at, window_seconds, count, entries[]}` | Recent tool usage filtered by agent/project |
| `resource://projects` | — | `list[project]` | All projects |
| `resource://project/{slug}` | `slug` | `{project..., agents[]}` | Project detail + agents |
| `resource://file_reservations/{slug}{?active_only}` | `slug`, `active_only?` | `list[file reservation]` | File reservations plus staleness metadata (heuristics, last activity timestamps) |
| `resource://message/{id}{?project}` | `id`, `project` | `message` | Single message with body |
| `resource://thread/{thread_id}{?project,include_bodies}` | `thread_id`, `project`, `include_bodies?` | `{project, thread_id, messages[]}` | Thread listing |
| `resource://inbox/{agent}{?project,since_ts,urgent_only,include_bodies,limit}` | listed | `{project, agent, count, messages[]}` | Inbox listing |
| `resource://mailbox/{agent}{?project,limit}` | `project`, `limit` | `{project, agent, count, messages[]}` | Mailbox listing (recent messages with basic commit ref) |
| `resource://mailbox-with-commits/{agent}{?project,limit}` | `project`, `limit` | `{project, agent, count, messages[]}` | Mailbox listing enriched with commit metadata |
| `resource://outbox/{agent}{?project,limit,include_bodies,since_ts}` | listed | `{project, agent, count, messages[]}` | Messages sent by the agent |
| `resource://views/acks-stale/{agent}{?project,ttl_seconds,limit}` | listed | `{project, agent, ttl_seconds, count, messages[]}` | Ack-required older than TTL without ack |
| `resource://views/urgent-unread/{agent}{?project,limit}` | listed | `{project, agent, count, messages[]}` | High/urgent importance messages not yet read |
| `resource://views/ack-required/{agent}{?project,limit}` | listed | `{project, agent, count, messages[]}` | Pending acknowledgements for an agent |
| `resource://views/ack-overdue/{agent}{?project,ttl_minutes,limit}` | listed | `{project, agent, ttl_minutes, count, messages[]}` | Ack-required older than TTL without ack |

### Client Integration Guide

1. **Fetch onboarding metadata first.** Issue `resources/read` for `resource://tooling/directory` (and optionally `resource://tooling/metrics`) before exposing tools to an agent. Use the returned clusters and playbooks to render a narrow tool palette for the current workflow rather than dumping every verb into the UI.
2. **Scope tools per workflow.** When the agent enters a new phase (e.g., "Messaging Lifecycle"), remount only the cluster's tools in your MCP client. This mirrors the workflow macros already provided and prevents "tool overload."
3. **Monitor real usage.** Periodically pull or subscribe to log streams containing the `tool_metrics_snapshot` events emitted by the server (or query `resource://tooling/metrics`) so you can detect high-error-rate tools and decide whether to expose macros or extra guidance.
4. **Fallback to macros for smaller models.** If you're routing work to a lightweight model, prefer the macro helpers (`macro_start_session`, `macro_prepare_thread`, `macro_file_reservation_cycle`, `macro_contact_handshake`) and hide the granular verbs until the agent explicitly asks for them.
5. **Show recent actions.** Read `resource://tooling/recent/60?agent=<name>&project=<slug>` (adjust window as needed) to display the last few successful tool invocations relevant to the agent/project.

See `examples/client_bootstrap.py` for a runnable reference implementation that applies the guidance above.

```json
{
  "steps": [
    "resources/read -> resource://tooling/directory",
    "select active cluster (e.g. messaging)",
    "mount tools listed in cluster.tools plus macros if model size <= S",
    "optional: resources/read -> resource://tooling/metrics for dashboard display",
    "optional: resources/read -> resource://tooling/recent/60?agent=<name>&project=<slug> for UI hints"
  ]
}
```

### Monitoring & Alerts

1. **Enable metric emission.** Set `TOOL_METRICS_EMIT_ENABLED=true` and choose an interval (`TOOL_METRICS_EMIT_INTERVAL_SECONDS=120` is a good starting point). The server will periodically emit a structured log entry such as:

```json
{
  "event": "tool_metrics_snapshot",
  "tools": [
    {"name": "send_message", "cluster": "messaging", "calls": 42, "errors": 1},
    {"name": "file_reservation_paths", "cluster": "file reservations", "calls": 11, "errors": 0}
  ]
}
```

2. **Ship the logs.** Forward the structured stream (stderr/stdout or JSON log files) into your observability stack (e.g., Loki, Datadog, Elastic) and parse the `tools[]` array.
3. **Alert on anomalies.** Create a rule that raises when `errors / calls` exceeds a threshold for any tool (for example 5% over a 5-minute window) so you can decide whether to expose a macro or improve documentation.
4. **Dashboard the clusters.** Group by `cluster` to see where agents are spending time and which workflows might warrant additional macros or guard-rails.

See `docs/observability.md` for a step-by-step cookbook (Loki/Prometheus example pipelines included), and `docs/GUIDE_TO_OPTIMAL_MCP_SERVER_DESIGN.md` for a comprehensive design guide covering tool curation, capability gating, security, and observability best practices.

Operations teams can follow `docs/operations_alignment_checklist.md`, which links to the capability templates in `deploy/capabilities/` and the sample Prometheus alert rules in `deploy/observability/`.

---

## Deployment quick notes

- **Direct uvicorn**: `uvicorn mcp_agent_mail.http:build_http_app --factory --host 0.0.0.0 --port 8765`
- **Python module**: `python -m mcp_agent_mail.http --host 0.0.0.0 --port 8765`
- **Gunicorn**: `gunicorn -c deploy/gunicorn.conf.py mcp_agent_mail.http:build_http_app --factory`
- **Docker**: `docker compose up --build`

### CI/CD

- Lint and Typecheck CI: GitHub Actions workflow runs Ruff and Ty on pushes/PRs to main/develop.
- Release: Pushing a tag like `v0.1.0` builds and pushes a multi-arch Docker image to GHCR under `ghcr.io/<owner>/<repo>` with `latest` and version tags.
- Nightly: A scheduled workflow runs migrations and lists projects daily for lightweight maintenance visibility.

### Log rotation (optional)

If not using journald, a sample logrotate config is provided at `deploy/logrotate/mcp-agent-mail` to rotate `/var/log/mcp-agent-mail/*.log` weekly, keeping 7 rotations.

### Logging (journald vs file)

- Default systemd unit (`deploy/systemd/mcp-agent-mail.service`) is configured to send logs to journald (StandardOutput/StandardError=journal).
- For file logging, configure your process manager to write to files under `/var/log/mcp-agent-mail/*.log` and install the provided logrotate config.
- Environment file path for systemd is `/etc/mcp-agent-mail.env` (see `deploy/systemd/mcp-agent-mail.service`).

### Container build and multi-arch push

Use Docker Buildx for multi-arch images. Example flow:

```bash
# Create and select a builder (once)
docker buildx create --use --name mcp-builder || docker buildx use mcp-builder

# Build and test locally (linux/amd64)
docker buildx build --load -t your-registry/mcp-agent-mail:dev .

# Multi-arch build and push (amd64, arm64)
docker buildx build \
  --platform linux/amd64,linux/arm64 \
  -t your-registry/mcp-agent-mail:latest \
  -t your-registry/mcp-agent-mail:v0.1.0 \
  --push .
```

Recommended tags: a moving `latest` and immutable version tags per release. Ensure your registry login is configured (`docker login`).

### Systemd manual deployment steps

1. Copy project files to `/opt/mcp-agent-mail` and ensure permissions (owner `appuser`).
2. Place environment file at `/etc/mcp-agent-mail.env` based on `deploy/env/production.env`.
3. Install service file `deploy/systemd/mcp-agent-mail.service` to `/etc/systemd/system/`.
4. Reload systemd and start:

```bash
sudo systemctl daemon-reload
sudo systemctl enable mcp-agent-mail
sudo systemctl start mcp-agent-mail
sudo systemctl status mcp-agent-mail
```

Optional (non-journald log rotation): install `deploy/logrotate/mcp-agent-mail` into `/etc/logrotate.d/` and write logs to `/var/log/mcp-agent-mail/*.log` via your process manager or app config.

See `deploy/gunicorn.conf.py` for a starter configuration. For project direction and planned areas, read `project_idea_and_guide.md`.

## CLI Commands

The project exposes a developer CLI for common operations:

- `serve-http`: run the HTTP transport (Streamable HTTP only)
- `migrate`: ensure schema and FTS structures exist
- `lint` / `typecheck`: developer helpers
- `list-projects [--include-agents]`: enumerate projects
- `guard install <project_key> <code_repo_path>`: install the pre-commit guard into a repo
- `guard uninstall <code_repo_path>`: remove the guard from a repo
- `share wizard`: launch interactive deployment wizard (auto-installs CLIs, authenticates, exports, deploys to GitHub Pages or Cloudflare Pages)
- `share export --output <path> [options]`: export mailbox to a static HTML bundle (see Static Mailbox Export section for full options)
- `share preview <bundle_path> [--port N] [--open-browser]`: serve a static bundle locally for inspection
- `share verify <bundle_path> [--public-key <key>]`: verify bundle integrity (SRI hashes and Ed25519 signature)
- `share decrypt <encrypted_path> [--identity <file> | --passphrase]`: decrypt an age-encrypted bundle
- `config set-port <port>`: change the HTTP server port (updates .env)
- `config show-port`: display the current configured HTTP port
- `clear-and-reset-everything [--force]`: DELETE the SQLite database (incl. WAL/SHM) and WIPE all contents under `STORAGE_ROOT` (including per-project Git archives). Use only when you intentionally want a clean slate.
- `list-acks --project <key> --agent <name> [--limit N]`: list messages requiring acknowledgement for an agent where ack is missing
- `acks pending <project> <agent> [--limit N]`: show pending acknowledgements for an agent
- `acks remind <project> <agent> [--min-age-minutes N] [--limit N]`: highlight pending ACKs older than a threshold
- `acks overdue <project> <agent> [--ttl-minutes N] [--limit N]`: list overdue ACKs beyond TTL
- `file_reservations list <project> [--active-only/--no-active-only]`: list file reservations
- `file_reservations active <project> [--limit N]`: list active file reservations
- `file_reservations soon <project> [--minutes N]`: show file reservations expiring soon

Examples:

```bash
# Interactive wizard: export + deploy to GitHub Pages (easiest)
./scripts/share_to_github_pages.py

# Export a static bundle with signing and encryption
uv run python -m mcp_agent_mail.cli share export \
  --output ./bundle \
  --signing-key ./keys/signing.key \
  --age-recipient age1abc...xyz

# Preview a bundle locally
uv run python -m mcp_agent_mail.cli share preview ./bundle --port 9000 --open-browser

# Verify bundle integrity
uv run python -m mcp_agent_mail.cli share verify ./bundle

# Change server port
uv run python -m mcp_agent_mail.cli config set-port 9000

# Install guard into a repo
uv run python -m mcp_agent_mail.cli guard install /abs/path/backend /abs/path/backend

# List pending acknowledgements for an agent
uv run python -m mcp_agent_mail.cli acks pending /abs/path/backend BlueLake --limit 10

# WARNING: Destructive reset (clean slate)
uv run python -m mcp_agent_mail.cli clear-and-reset-everything --force
```

## Client integrations

Use the automated installer to wire up supported tools automatically (e.g., Claude Code, Cline, Windsurf, OpenCode). Run `scripts/automatically_detect_all_installed_coding_agents_and_install_mcp_agent_mail_in_all.sh` or the one-liner in the Quickstart above.
