# AgentTrust — Implementation State

## Status: ✅ ALL PHASES COMPLETE

All 23 tasks across 5 phases implemented and tested.

## Phase 1: Foundation ✅
- Project scaffold (pyproject.toml, docker-compose, alembic, config)
- Database models: Agent, Interaction (TimescaleDB hypertable), TrustScore, Dispute, Attestation, AlertSubscription
- AgentAuth integration layer (MCP client, Redis introspection cache, standalone Ed25519 fallback)
- FastMCP server entry point with CLI args (--transport, --port)
- Agent registration tools: register_agent, link_agentauth, whoami, get_agent_profile, search_agents
- Test infrastructure: SQLite fixtures, Redis mock, AgentAuth mock, factories

## Phase 2: Scoring ✅
- report_interaction + get_interaction_history (trust.report scope, mutual confirmation)
- Bayesian Beta score engine (α=2,β=2 prior, time decay, credibility weighting, dispute penalties)
- check_trust (Redis 60s cache), get_score_breakdown (trust.read), compare_agents
- Background workers: recompute_score, refresh_all_scores, expire_attestations
- MCP resources: trust://agents/{id}/score, trust://agents/{id}/history, trust://leaderboard/{type}

## Phase 3: Trust ✅
- Ed25519 keypair management + EdDSA JWT attestation signing (cryptography package)
- issue_attestation (trust.attest.issue), verify_attestation (no auth, revocation check)
- file_dispute (trust.dispute.file), resolve_dispute (trust.dispute.resolve + AgentAuth RBAC)
- Dismissed dispute penalty (filer): max(1 - n*0.01, 0.90); upheld: max(1 - n*0.03, 0.50)
- MCP resources: trust://agents/{id}/attestations, trust://disputes/{id}, trust://health

## Phase 4: Advanced ✅
- MCP prompts: evaluate_counterparty (PROCEED/CAUTION/DECLINE), explain_score_change, dispute_assessment
- subscribe_alerts (trust.admin scope) + alert_dispatcher worker (delta-threshold notifications)
- SybilDetector: ring_reporting (mutual + multi-hop BFS cycles up to 6 hops), burst_registration (3 windows: 1h/24h/7d), reporting_velocity (>50 distinct negatives/24h), delegation_chain (depth>3)
- Redis sliding-window rate limiting: root=300, delegated=120, standalone=60, ephemeral=30, anon=10 req/min

## Phase 5: Polish ✅
- Structured logging: configure_logging() JSON/console, bind_request_context for correlation IDs
- scripts/register_scopes.py: registers trust.* scopes with AgentAuth MCP
- scripts/seed_test_agents.py: seeds Alice/Bob/Eve for development
- README.md: comprehensive docs with tools, resources, prompts, score algorithm, env vars
- Dockerfile + docker-compose full stack (postgres, redis, agent-trust, worker)

## Security Hardening ✅
Five rogue-agent attack vectors identified in threat model (docs/reports/20260318-03-audit-report.md) and resolved:

- **Slow Sybil Army** — burst_registration now checks 3 windows (±1h/±12h/±84h, thresholds 5/20/50). Multi-hop BFS ring detection (A→B→C→D→A chains up to 6 hops) added alongside the existing mutual-pair check.
- **Trust Amplification / Score Bomb** — new `reporting_velocity` Sybil signal fires when an agent files ≥50 distinct failure/timeout reports in 24 hours. `report_interaction` returns a `warnings` field when the threshold is exceeded.
- **Attestation Race Window** — revocation now compares each attestation's `score_snapshot` issuance score against the current score. Cumulative drops across multiple cycles (e.g. 0.95→0.87→0.79) now correctly trigger revocation. Threshold configurable via `ATTESTATION_CUMULATIVE_REVOCATION_THRESHOLD`.
- **Dispute Harassment Campaign** — per-filer daily cap (10 disputes/24h) and per-filer open cap (30 open disputes across all targets) added. Configurable via `DISPUTE_FILER_DAILY_CAP` and `DISPUTE_FILER_OPEN_CAP`.
- **Context Field Prompt Injection** — `_scan_for_injection()` added to detect 14 adversarial patterns in context JSONB. `report_interaction` and `get_interaction_history` return `warnings`/`context_warnings` on hits. Writes are never blocked.

## Test Coverage
246+ tests across:
- tests/test_auth/ — AgentAuth provider, standalone, cache
- tests/test_engine/ — score algorithm (property-based), workers, crypto, sybil detection
- tests/test_tools/ — all 16 tools, prompts, alert subscriptions
- tests/test_integration/ — AgentAuth flow, standalone flow
- tests/test_ratelimit.py — rate limiter behavior
- tests/test_logging_config.py — logging configuration

## Key Files
- src/agent_trust/server.py — FastMCP server, all tools/resources/prompts registered
- src/agent_trust/engine/score_engine.py — Bayesian scoring algorithm
- src/agent_trust/auth/agentauth.py — AgentAuth MCP client integration
- src/agent_trust/ratelimit.py — Redis sliding-window rate limiter
- src/agent_trust/engine/sybil_detector.py — Sybil detection engine
- alembic/versions/ — DB migrations including TimescaleDB hypertable + delegated_by
