Overview

Westminster records from the official UK Parliament Bills, Members, Commons and Lords Votes, Hansard, Written Questions, and Committees APIs. Search parliamentary business, retrieve selected records and source links, and trace members, bills, votes, answers, and committee publications across their distinct identifiers. Runs as a stdio process, a local Streamable HTTP server, or the public hosted endpoint above; no API key is required.

Tools

Capability reference

ukparl_lookup_reference _tool

• topic: identifiers, coverage, bill_stages, bill_types, parties, departments, or answering_bodies; live directories default to 10 rows, capped at 20, with optional nameContains AND-token filtering
• house is required only for parties; that directory covers active parties in the selected House, not every historical party. Static guides accept neither House nor name filters
• Identifier guidance distinguishes reference stageId from bill-specific billStageId, House-scoped division IDs, Questions API IDs from UINs, and committee person IDs from Members API IDs
• departments IDs feed ukparl_search_bills.departmentId; they are distinct from Written Questions answering-body IDs

ukparl_search_bills _tool

• Optional query, current house, originatingHouse, sessionId, memberId, departmentId, stageIds, and billTypeIds; each ID array accepts up to 20 entries. Defaults to 10 bills, capped at 20
• sortOrder: TitleAscending, TitleDescending, DateUpdatedAscending, or DateUpdatedDescending; omission preserves source ordering. Optional isDefeated and isWithdrawn accept true or false. inAmendableStage: true restricts to amendable stages; false leaves results unrestricted
• Results are detailLevel: "summary" with billId, provenance, and collection continuation; no current-session scope is inferred. Resolve reference filters with ukparl_lookup_reference

ukparl_get_bill _tool

• Required billId; section defaults to overview, or selects stages, stage, publications, amendments, amendment, motions, or motion. Collections default to 20 records, capped at 50
• Stage, amendment, and motion selections require the bill-specific billStageId from stages; singular amendment/motion retrieval also needs itemId from the parent collection (amendmentId for amendments, motion.id for motions). Amendment/motion lists are summaries; singular selectors retrieve complete text
• Only section: "amendments" accepts amendmentNumber (a string retaining letter suffixes), official decision, and sponsoring memberId filters. Filters apply before source pagination; singular retrieval still uses itemId
• Missing entities return found: false with guidance. section: "publications" derives legislationHandoff (authoritative_link, not_enacted, or unavailable) from the bill's published documents; only supplied legislation.gov.uk links establish a statute handoff
• Overview reads metadata only. Unless isAct is explicitly false, its unavailable handoff explains that publications remain unchecked; repeat with the same billId and section: "publications" to discover statute links

ukparl_search_members _tool

• Optional name, constituency (source location text: constituency name or postcode), partyId, and house; currentOnly defaults to false, including current and former members. Defaults to 10 rows, capped at 20
• asOf selects membership on a real YYYY-MM-DD date and accepts name, pagination, and currentOnly: false alongside it; returned latest profile fields are not a historical snapshot
• Summary hits carry memberId for ukparl_get_member, source, and page; unknown source fields remain absent or null

ukparl_get_member _tool

• Required memberId; section: profile (default), roles, committee_seats, contact, interests, or voting. Roles without category returns an availability outline; select a returned category for whole role periods
• house is required for interests and voting, and omitted elsewhere. Local histories default to 20 rows, capped at 50; voting uses native 20-row pages regardless of limit
• found and guidance distinguish missing members and unavailable source collections. Interest trees and committee relationships retain source pointers; voting preserves recorded lobby and teller facts without inferring abstention or lifetime participation

ukparl_search_divisions _tool

• Required house: commons or lords; mode: search (default), detail, voters, or party_totals. Search accepts query, memberId, and inclusive startDate / endDate; defaults to 5 divisions, capped at 10
• Other modes require a divisionId from the same House. Voters default to 20 rows, capped at 50, with exact source party labels and lobby: Commons aye, no, not_recorded; Lords content, not_content
• Detail preserves headline counts and teller identities; partyTotals counts listed non-tellers and tellers separately. not_recorded is the source list, never an abstention claim; member searches include teller participation
• Search with memberId returns memberVote: { memberId, lobby, wasTeller } on each result, using the House's recorded lobby. A missing result does not imply abstention

ukparl_search_hansard _tool

• Optional query, memberId, house, inclusive startDate / endDate, and numeric debateSectionId; defaults to 5 contributions, capped at 20. Dates are YYYY-MM-DD, with no inferred window
• detailLevel: "complete" carries full source contribution text, including HTML; summary means the source supplied only a preview. Section filtering does not establish a complete debate transcript
• coverage reports historical limitations, including the 2004–2006 website warning; empty results do not prove no debate occurred. Narrow date windows after timeouts; use ukparl_lookup_reference with topic: "coverage" for archive guidance

ukparl_search_questions _tool

• mode: "search" (default) accepts query, uin, asking-member memberId, answeringMemberId, house, up to 20 answeringBodyIds, answered, and inclusive tabledFrom / tabledTo / answeredFrom / answeredTo dates (YYYY-MM-DD). Defaults to 10 previews, capped at 20
• Search includes all sessions and withdrawn questions; omitted answered includes either state. mode: "detail" takes a returned questionId alone for complete question/answer HTML, corrections, and attachment metadata; a UIN is not a questionId
• uin retains leading zeros and normalizes the HL prefix. Without dates, reused UINs can return candidates across sessions; combine tabledFrom / tabledTo and House filters to narrow them, then retrieve a returned questionId
• Results distinguish detailLevel: "summary" from "complete"; detail misses return found: false with guidance. Attachments are links and metadata, not downloaded files

ukparl_get_committee _tool

• mode: "search" (default) accepts query, house (commons, lords, joint), and status: Current|Former|All, default 10/cap 20. detail, members, and publications require committeeId; inquiries accepts it optionally for committee-specific or cross-committee discovery. Nested collections default to 20/cap 50
• inquiry requires businessId; publication requires publicationId. businessId can also filter publications. membership selects all (default), current, or former in members mode; query in inquiries/publications requires at least two characters
• inquiries accepts status: Open|Closed, acceptingEvidence, inclusive openedFrom / openedTo dates, and sortOrder: DateOpenedNewest|DateOpenedOldest|PublicationDateAscending|PublicationDateDescending. acceptingEvidence: true restricts to accepting businesses; false is unrestricted. All business types remain labelled by isInquiry
• publications accepts repeated publicationTypeIds, inclusive publishedFrom / publishedTo dates, and sortOrder: PublicationDateAscending|PublicationDateDescending|ResponseDateAscending|ResponseDateDescending. Omitted filters preserve source defaults
• evidence requires businessId and evidenceType: written|oral; evidence_detail requires evidenceId and the same evidenceType. These IDs occupy separate written/oral namespaces. Records retain typed entities and sourcePath relationships, witnesses, organisations, dates, source state, and supplied document links. Publications remain separate reports, responses, and correspondence; no mode downloads or extracts documents

Features

Built on @cyanheads/mcp-ts-core: stdio and Streamable HTTP transports, pluggable auth (none / jwt / oauth), swappable storage (in-memory, filesystem, Supabase, Cloudflare KV/R2/D1), structured logging with optional OpenTelemetry tracing.

UK Parliament-specific:

• Keyless, read-only access to seven official Westminster API origins; devolved legislatures are outside scope
• Separate identifier namespaces and explicit source selections, with no inferred current session or date window
• Shared per-origin backpressure, bounded retries, and a 45-second call deadline across related requests
• Hansard coverage is source-specific: the archive starts on 22 November 1803, the Spoken API minimum date is unknown, and there is no automatic historical-archive fallback

Agent-friendly output:

• Provenance — source API, request URL, retrieval timestamp, and licence link accompany source records; applied reports effective selections and limits
• Whole-record pagination — page.returned, hasMore, and nextCursor describe actually emitted records, with total only when known; every response stays under 24,000 bytes across both output surfaces
• Lossless large records — delivery: "full" | "outline" | "fragment"; an oversized record returns contentPage descriptors, and repeating the original inputs plus each contentCursor reconstructs it exactly
• Compact JSON — content renders complete values as reversible JSON blocks with clickable source links. An outline entry's optional jsonValue is complete JSON text you can decode directly; its contentCursor still retrieves the same value. Fragment sizes adapt to the response budget; concatenate their JSON text before decoding
• Explicit recovery — invalid_cursor restarts a selection; source_changed restarts content retrieval after an upstream revision. Search previews, missing records, and unavailable collections remain distinct
• Selector errors name each missing or incompatible field and its repair in deterministic order, before network requests; existing error reasons and recovery hints remain stable

Getting started

Connect to the hosted instance, no install:

claude mcp add --transport http uk-parliament-mcp-server https://uk-parliament.caseyjhand.com/mcp

Or run it locally:

claude mcp add uk-parliament-mcp-server -- npx -y @cyanheads/uk-parliament-mcp-server

For other clients, add this to the MCP config file:

{
  "mcpServers": {
    "uk-parliament-mcp-server": {
      "command": "npx",
      "args": ["-y", "@cyanheads/uk-parliament-mcp-server"]
    }
  }
}

No API key is required. For Docker or a source build, see Running the server.

Configuration

See .env.example for the common framework overrides. There are no server-specific environment variables.

Running the server

Local development

Requires Bun v1.4.0 or higher (or Node.js v24+) and internet access to the official Parliament APIs.

• Clone and install:

  shCopy

  git clone https://github.com/cyanheads/uk-parliament-mcp-server.git
  cd uk-parliament-mcp-server && bun install
  cp .env.example .env
  # edit .env for transport, logging, or authentication overrides as needed
  

• Build and run the production version:

  shCopy

  # One-time build
  bun run rebuild
  
  # Run the built server
  bun run start:http
  # or
  bun run start:stdio
  

• Run checks and tests:

  shCopy

  bun run devcheck  # Lints, formats, type-checks, and more
  bun run test      # Runs the test suite
  

Docker

docker run --rm -p 3010:3010 ghcr.io/cyanheads/uk-parliament-mcp-server:latest

The image defaults to HTTP transport, stateless sessions, and logs to /var/log/uk-parliament-mcp-server. For an MCP client using stdio, use "command": "docker" with "args": ["run", "-i", "--rm", "-e", "MCP_TRANSPORT_TYPE=stdio", "ghcr.io/cyanheads/uk-parliament-mcp-server:latest"]. Build locally with docker build -t uk-parliament-mcp-server .; --build-arg OTEL_ENABLED=false omits the optional OpenTelemetry peers.

Project structure

Development guide

See CLAUDE.md for development guidelines and architectural rules. The short version:

• Handlers throw, framework catches — no try/catch in tool logic
• Use ctx.log for logging, ctx.state for storage
• Register new tools and resources in the createApp() arrays in src/index.ts
• Wrap external API calls: validate raw → normalize to domain type → return output schema; never fabricate missing fields

Contributing

Issues are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

License

Apache-2.0 — see LICENSE for details.

Contains Parliamentary information licensed under the Open Parliament Licence v3.0 where applicable. Personal data, parliamentary marks, and third-party rights are excluded; preserve the source's notices and check rights before reusing excluded material. This software is independent and does not imply parliamentary endorsement.