FBI Crime Data MCP Server

An MCP (Model Context Protocol) server that provides access to the FBI's Crime Data Explorer API.

Query crime statistics, arrest data, hate crimes, NIBRS incidents, law enforcement employment, and more — directly from any MCP-compatible client.

Created for data journalists, researchers, and anyone interested in exploring US crime data with the power of language models. Initially created for use by the Policy Analyst Agent of the qsv Claude Cowork plugin.

Features

• 17 tools covering a wide range of crime data topics
  • Crime trends and Summary Reporting System (SRS) crime data
  • National Incident Based Reporting System (NIBRS) incident-based data and national estimates
  • Arrest statistics with demographic breakdowns
  • Hate crime incidents by bias motivation
  • Expanded homicide and property crime details
  • Police employment, Law Enforcement Officers Killed and Assaulted (LEOKA), Law Enforcement Suicide Data Collection (LESDC), and use of force
  • Agency lookup, reference data, cache management, and spillover reading
• Geographic query levels — national, state, and agency for most tools; some also support region (get_police_employment, get_nibrs_estimation) or agency-type / population-size breakdowns (get_nibrs_estimation) — all with automatic parameter validation
• Smart yearly aggregation — monthly API data is automatically rolled up into yearly totals (sums for counts, unweighted averages for rates, last value for population), with an option for monthly granularity. Years with fewer than 12 months of data are flagged in a _partial_years key so partial-year sums are never mistaken for annual totals
• Tiered disk-backed caching — 90-day time-to-live (TTL) for stable data (trends, reference, summaries, NIBRS estimation), 30-day TTL for dynamic data (incidents, arrests, agency lookups), and 1-day TTL for the homepage summary (refresh dates change frequently). Transient errors (timeouts, HTTP 5xx, rate-limit responses) are never cached
• Spillover handling — responses exceeding 128K characters are saved to disk with a preview returned, so large queries are never silently truncated
• Input validation — date format/ordering checks, offense and bias code validation, and level-based parameter requirements with clear error messages
• Sliding-window rate limiting — 1,000 requests/hour with transparent wait-time feedback
• Reference tools for agency lookups (by state, Originating Agency Identifier (ORI), or district with name filtering) and code translations

Quick Start

1. Get a free API key from api.data.gov

2. Run with Claude Desktop — add to your claude_desktop_config.json:

{
  "mcpServers": {
    "fbi-crime-data": {
      "command": "uvx",
      "args": ["fbi-crime-data-mcp"],
      "env": {
        "FBI_API_KEY": "your-api-key-here"
      }
    }
  }
}

3. Or run directly:

FBI_API_KEY=your-key uvx fbi-crime-data-mcp

Available Tools (17)

Core Crime Data

Specialized Crime Data

Law Enforcement Data

Overview

Reference & Lookup

Large Responses

When a tool response exceeds 128,000 characters, the full result is saved to ~/.cache/fbi-crime-data-mcp/spillover/ and a truncated preview is returned with the file path. To avoid this, narrow your query (shorter date range, specific state/agency).

The preview, not the full payload, is what gets cached, so the cache and the spillover directory belong together. Clear both with manage_cache action="clear" rather than deleting the spillover directory by hand; otherwise cached previews point at files that no longer exist until the cache entry expires.

Data Sources

All data comes from the FBI's Crime Data Explorer API, which provides Uniform Crime Reporting (UCR) data including both the Summary Reporting System (SRS) and the National Incident-Based Reporting System (NIBRS).

API Rate Limits

• Registered key: 1,000 requests per hour (rolling window)
• DEMO_KEY: 30 requests per IP per hour

The server includes a built-in rate limiter (1,000 req/hr). The DEMO_KEY limit is enforced API-side.

For more info on the FBI's Crime Data API, see https://cde.ucr.cjis.gov/LATEST/webapp/#/pages/docApi.

Development

# Install dependencies
uv sync

# Run the server locally
FBI_API_KEY=your-key uv run fbi-crime-data-mcp

# Run tests (offline by default — never hits the network)
uv run pytest

# Run integration tests against the live API.
# DEMO_KEY works, but is capped at 30 requests per IP per hour.
FBI_API_KEY=your-key uv run pytest -m integration

License

MIT