# Local Browser History MCP

An MCP server that allows searching local browser history files through a unified interface. Works with MCP-compatible clients and as a tool for the [llm](https://llm.datasette.io/) CLI tool.

The tool currently supports Chrome, Firefox, and Safari browser histories.

# Installation

## MCP Server (Claude Desktop, Claude Code, etc.)

Install with MCP support:

```sh
pip install llm-tools-browser-history
```

Quick start for Claude Desktop - add to `~/Library/Application Support/Claude/claude_desktop_config.json`:

```json
{
  "mcpServers": {
    "browser-history": {
      "command": "uvx",
      "args": [
        "--from",
        "llm-tools-browser-history",
        "browser-history-mcp",
      ]
    }
  }
}
```

Once configured, you can use the `browser_history` tool in conversations with Claude.

Note that the CLI supports additional options as needed:

```sh
browser-history-mcp --help
```

### Query Parameter Whitelist

By default, query parameters are stripped from URLs to protect sensitive data (session IDs, auth tokens, etc.). A built-in whitelist preserves useful parameters like search terms and video IDs for well-known domains (Google `q`, YouTube `v`, etc.).

To supply your own whitelist, create a YAML file mapping domains to allowed parameter keys:

```yaml
# my-whitelist.yaml
google.com:
  - q
  - tbm
youtube.com:
  - v
  - t
amazon.com:
  - k
  - field-keywords
github.com:
  - q
```

Then pass it via `--qp-whitelist`:

```sh
browser-history-mcp --qp-whitelist my-whitelist.yaml
```

Domain matching walks up subdomains: a URL on `images.google.com` will match the `google.com` rule if no `images.google.com` rule exists. Domains not in the whitelist have all query parameters stripped (the previous default behaviour).

The database schema includes a `stripped_qp` column that records the names (never values) of removed parameters, and a `domain` column for the URL's domain.

### Debugging with --query

Use `--query` to run a single SQL query, print results, and exit without starting the MCP server:

```sh
browser-history-mcp --query "SELECT url, title, domain, stripped_qp FROM browser_history LIMIT 5"
```


Note: Safari browser history is blocked by TCC - you would need to explicitly allow access to your Safari data (I don't yet have instructions for this, but welcome contributions!)

## llm CLI tool

Install for use with llm:

```sh
# install the plugin:
llm install llm-tools-browser-history

# see available plugins:
llm plugins

...
  {
    "name": "llm-tools-browser-history",
    "hooks": [
      "register_tools"
    ],
    "version": "0.1.0"
  },
...
```

Examples:

```sh
# Search for pages mentioning yosemite in title or URL
llm -T llm_time -T BrowserHistory "what pages about yosemite did I look up recently?"

# Limit to Firefox and Safari sources
llm -T llm_time -T 'BrowserHistory(["firefox","safari"])' "what pages about yosemite did I look up recently?"

llm -T BrowserHistory "show a table of how much I used each browser over the past year by month"
```


# Security and Privacy

**Warning**: This tool has read-access to your entire browser history. You risk sending
this highly sensitive personal data to third-party services (like OpenAI).

See [the lethal trifecta article](https://simonw.substack.com/p/the-lethal-trifecta-for-ai-agents) for more information about the risks of using tools like this with LLMs.

To mitigate the risks of data leakage:
- Only runs queries against a copy of the target browser's history database (so any malicious modification has no effect).
- Limits the number of results to no more than 100 records per tool use.
- Does not return the entire browser history record. This tool will return a subset of fields (URL, title, visit date). Query parameters are filtered by a configurable whitelist (only safe keys like search terms are preserved; all others are stripped). Timestamps only include the date (not the time).

## Dev setup

```bash
make setup
make test

pip install -e .

llm -T llm_time -T BrowserHistory --td "what pages about yosemite did I look up recently?"
```

# Documentation

* [MCP Setup Guide](docs/MCP_SETUP.md) - Setting up the MCP server for Claude Desktop, Claude Code, etc.

## ADRs

* [1. Python project](docs/adr/0001-python-project.md)
* [2. Expose browser history as an LLM toolbox tool](docs/adr/0002-browser-tool.md)
* [3. Normalized SQL interface](docs/adr/0003-normalized-sql-interface.md)
* [4. MCP Standalone Service](docs/adr/0004-mcp-standalone-service.md)
