DataDawn Server

An MCP (Model Context Protocol) server that gives AI agents direct access to two large public-interest databases:

• 990 Database (data.datadawn.org) — IRS 990 nonprofit filings, foundation grants, DAF disbursements, officers, and the IRS Business Master File for ~2M tax-exempt organizations.
• OpenRegs Database (regs.datadawn.org) — Federal Register documents, regulations.gov dockets/documents/comments, congressional legislation, floor speeches, stock trades, lobbying filings, campaign finance, hearings, nominations, and more.

The server proxies queries to the Datasette JSON API — no API keys or database files needed.

Install

pip install mcp httpx

Or with uv:

uv pip install mcp httpx

Tools

990 Database (data.datadawn.org)

Tool	Description
search_nonprofit(query, state?)	Search the IRS Business Master File by org name. Starting point for finding EINs.
lookup_ein(ein)	Look up an org by EIN. Returns BMF data + recent 990 filings with financials.
search_grants(recipient, min_amount?)	Search foundation grants (~12.5M) by recipient name.
search_daf_grants(recipient)	Search Donor-Advised Fund disbursements by recipient name.
org_officers(ein)	Get officers/directors/key employees for an org (most recent filing).
org_grants_made(ein, limit?)	Get grants made by a foundation (by funder EIN).
run_990_sql(sql)	Run arbitrary read-only SQL against the 990 database.

OpenRegs Database (regs.datadawn.org)

Tool	Description
search_federal_register(query, type?, year?)	Search ~1M Federal Register documents (1994-present).
search_legislation(query, congress?)	Search congressional bills (~168K, Congresses 93-119).
lookup_member(name)	Find a member of Congress by name. Returns bioguide_id for cross-referencing.
member_trades(bioguide_id)	Get stock trades disclosed by a member of Congress.
search_lobbying(query, year?)	Search ~1.9M lobbying filings by client or registrant.
search_comments(query, agency?)	Search ~3.9M public comments on federal regulations.
run_openregs_sql(sql)	Run arbitrary read-only SQL against the OpenRegs database.

Add to Claude Code

Option 1: CLI command (recommended)

claude mcp add --transport stdio --scope user datadawn -- python /path/to/datadawn-mcp/server.py

This makes the server available in all your Claude Code sessions.

Option 2: Project-scoped

claude mcp add --transport stdio datadawn -- python /path/to/datadawn-mcp/server.py

Option 3: Manual JSON config

Add to ~/.claude.json under the mcpServers key:

{
  "mcpServers": {
    "datadawn": {
      "type": "stdio",
      "command": "python",
      "args": ["/path/to/datadawn-mcp/server.py"]
    }
  }
}

Verify

After adding, restart Claude Code (or start a new session) and run:

/mcp

You should see "datadawn" listed with 14 tools available.

Test

Quick test with MCP CLI

cd /path/to/datadawn-mcp
mcp dev server.py

This opens the MCP Inspector in your browser where you can call tools interactively.

Test from Python

import asyncio
import httpx

async def test():
    # Direct Datasette query (same thing the MCP server does internally)
    url = "https://data.datadawn.org/990data_public.json"
    params = {
        "sql": "SELECT name, ein, state FROM bmf WHERE ein IN (SELECT ein FROM fts_bmf WHERE fts_bmf MATCH 'ford foundation') LIMIT 5",
        "_shape": "objects",
    }
    async with httpx.AsyncClient() as client:
        resp = await client.get(url, params=params)
        print(resp.json()["rows"])

asyncio.run(test())

Test with Claude Code

After adding the MCP server, try these prompts in Claude Code:

Search for the Ford Foundation's EIN and recent filings.

What stock trades has Nancy Pelosi disclosed?

Find lobbying filings by Google in 2024.

Search for EPA rules about PFAS chemicals.

How it works

Each tool constructs a SQL query, sends it to the Datasette JSON API via HTTP, and formats the response as human-readable text. The server uses the stdio transport by default, communicating with Claude Code over stdin/stdout using JSON-RPC.

Claude Code <--stdio--> server.py <--HTTPS--> Datasette JSON API
                                                 |
                                       data.datadawn.org (990)
                                       regs.datadawn.org (OpenRegs)

Notes

• All queries are read-only SELECT statements. The Datasette API enforces this.
• Results are limited to 25-50 rows by default to keep responses manageable.
• The run_990_sql and run_openregs_sql tools accept arbitrary SQL for advanced queries.
• For the 990 database: always filter return_type IN ('990','990EZ') to exclude 990-T filings, and filter grant_type = 'paid' on grants unless you want future commitments.
• Full schema documentation lives in the public companion repos: openregulations-public (openregs_schema.md) and 990database-public (990_schema.md).

License

CC0 1.0 Universal — see LICENSE.