Congress Member Votes

@pipeworx/congress-member-votes

How each U.S. House member voted, how often they were there, and how often they vote with their party, from the U.S. House Clerk's roll-call votes.

Part of Pipeworx — an MCP gateway connecting AI agents to 1875+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

• member_vote_positions(bioguide_id | name [+ state], bill?, question_contains?, from_roll?, to_roll?, limit?, congress?, session?) — one member's position (Yea, Nay, Present, Not Voting, or not on the roll) on roll calls, newest first. Answers "how did Rep. X vote on bill Y".
• member_attendance_party_line(bioguide_id | name [+ state], from_roll?, to_roll?, congress?, session?) — attendance and party-line share for one member over a session or roll range. Every figure carries its denominator and exclusions; a figure that cannot be computed is null with a stated reason, never 0% or 100%.
• roll_call_positions(roll_number, party?, state?, position?, congress?, session?) — every member's position on one roll call, with party tallies.

What the derived figures mean

• Attendance denominator: recorded roll calls in the range on which the member was on the roll. Quorum calls and Speaker elections are excluded (and counted in excluded_rolls). attended = Yea + Nay + Present; missed = Not Voting.
• Not on the roll is not Not Voting. A member absent from a roll entirely (not yet seated, or already gone) is excluded from the denominator and counted separately as not_on_roll_excluded.
• with_party_majority: of the member's Yea/Nay votes, the share matching what a strict majority of their own party's Yea/Nay voters did. Includes lopsided votes, so it runs high. Party-tied rolls are excluded and counted.
• party_unity: the same, restricted to rolls where a majority of Democrats opposed a majority of Republicans.
• The Speaker is listed on a roll only when voting, so a Speaker's missed-vote count cannot be derived; attendance is returned as null with that reason (party-line is still computed over the votes cast).
• Party is the member's party at their latest roll call. Independents have no D-versus-R majority, so no party-line figure is computed for them.

Auth

Keyless.

Coverage

House only. 119th Congress, sessions 1 and 2. Other Congresses and the Senate return a named reason. Senate roll-call records could not be read: the Secretary of the Senate's site refused every request (HTTP 403) from this service and from a separate machine on 2026-10-23.

Data sources

• U.S. House Clerk, roll-call votes. US federal data, public domain.

Rolls are held as a compact member-by-roll table, generated by scripts/bake-congress-member-votes.mjs (the refresh path), uploaded at deploy and injected into the pack (pack-baked-indexes.json). Rolls newer than the table are read from the Clerk live on each call (up to 40), so every response states the last roll it covers (rolls_covered), how many were added live (live_topup) and data_as_of. If the live read fails the response says so and covers only the stored rolls.

The Clerk answers a roll that does not exist with an HTTP 200 stub rather than a 404; the pack treats that as "no such roll" and any other non-record body as a fault.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "congress-member-votes": {
      "url": "https://gateway.pipeworx.io/congress-member-votes/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/congress-member-votes/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — ask_pipeworx, discover_tools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Both URLs reach the same gateway and the same 1875+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

No MCP client? Call it over HTTP

curl -X POST https://gateway.pipeworx.io/v1/tools/member_vote_positions \
  -H 'Content-Type: application/json' \
  -d '{"bioguide_id":"P000197","bill":"H CON RES 14","congress":119,"session":1}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/member_vote_positions. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.

Standalone (no gateway account)

This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:

{
  "mcpServers": {
    "congress-member-votes": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-congress-member-votes"]
    }
  }
}

Or run it directly to confirm it starts:

npx -y @pipeworx/mcp-congress-member-votes

It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call for only this pack's tools — none of the shared meta-tools the gateway connection above adds. Same source, same tools, no ask_pipeworx routing.

Using with ask_pipeworx

Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:

ask_pipeworx({ question: "your question about Congress Member Votes data" })

The gateway picks the right tool and fills the arguments automatically.

More

• Docs and guides
• pipeworx.io

License

MIT