openfec-mcp-server

Public Hosted Server: https://openfec.caseyjhand.com/mcp

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Overview

US federal campaign finance data from the FEC's OpenFEC API. Search candidates, committees, and filings, trace contributions (Schedule A), disbursements (Schedule B), and independent and coordinated party expenditures (Schedules E/F), and look up election races, legal documents, and filing deadlines. Runs as a stdio process, a local Streamable HTTP server, or the public hosted endpoint above.

Tools

Tool	Description
openfec_search_candidates	Find federal candidates by name, state, office, party, or cycle; fetch one by FEC ID with financial totals
openfec_search_committees	Find political committees by name, type, candidate affiliation, or state; fetch one by FEC ID
openfec_get_committee_totals	Pre-aggregated financial totals for one committee by cycle, or ranked across committees of one entity type
openfec_search_contributions	Itemized contributions (Schedule A), or aggregates by size, state, employer, or occupation
openfec_search_disbursements	Itemized committee spending (Schedule B), or aggregates by purpose or recipient
openfec_search_expenditures	Independent expenditures (Schedule E) supporting or opposing candidates, itemized or totaled per candidate
openfec_search_coordinated_expenditures	Coordinated party expenditures (Schedule F) made on behalf of a candidate
openfec_search_filings	FEC filings and reports by committee, candidate, form type, or date range
openfec_lookup_elections	Candidates in a federal race with their fundraising totals, or an aggregate race summary
openfec_search_legal	Advisory opinions, enforcement cases, alternative dispute resolutions, administrative fines, and statutes
openfec_get_legal_document	One legal document in full, including the arrays search trims away, paged by entry when too large for one response
openfec_lookup_calendar	FEC calendar events, filing deadlines, and election dates

Resources

Resource	Description
openfec://candidate/{candidate_id}	Candidate profile with financial totals and principal committees
openfec://committee/{committee_id}	Committee profile with type, designation, and financial summary
openfec://election/{cycle}/{office}	Presidential race with candidate financial totals
openfec://election/{cycle}/{office}/{state}	Senate or at-large House race with candidate financial totals
openfec://election/{cycle}/{office}/{state}/{district}	House district race with candidate financial totals

The same data is reachable through openfec_search_candidates, openfec_search_committees, and openfec_lookup_elections for tool-only clients.

Prompts

Prompt	Description
openfec_money_trail	Trace the money around a candidate: direct fundraising, PAC support, independent expenditures, and party spending
openfec_campaign_analysis	Structured analysis of a candidate's financial position

Capability reference

openfec_search_candidates tool

• query name search filtered by state, district, office, party, cycle, election_year, incumbent_challenge, candidate_status, and has_raised_funds, up to 100 per page; or a candidate_id lookup (H/S/P + eight letters or digits) returning one full record
• include_totals (default on for an ID lookup) adds per-cycle totals rows and caps a search page at 35 candidates when cycle or election_year scopes the totals, 5 when they span every cycle; candidates the totals fetch didn't reach are listed in missing_totals
• Typed errors: candidate_not_found, inputs_not_applicable_to_id_lookup

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openfec_search_committees tool

• query name search filtered by candidate_id, state, party, committee_type, designation, cycle, and treasurer_name, up to 100 per page; or a committee_id lookup (C + eight digits)
• Typed errors: committee_not_found, inputs_not_applicable_to_id_lookup

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openfec_get_committee_totals tool

• mode: "single" (default) takes a committee_id and returns one row per two-year cycle; mode: "by_entity_type" ranks every committee of one entity_type (presidential, pac, party, pac-party, house-senate, ie-only), filterable by state, type, designation, organization type, and receipts/disbursements bounds; up to 100 per page
• Rows carry receipts, disbursements, cash on hand, debts, and the itemized/unitemized split; the output mode says whether rows are cycles or committees
• Typed errors: committee_id_required_for_single_mode, entity_type_required_for_group_mode, committee_totals_not_found

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openfec_search_contributions tool

• itemized (default) needs a committee_id and filters by contributor name, employer, occupation, city, state, ZIP, date and amount ranges, and is_individual, 30 rows per page; by_size / by_state take a committee_id or candidate_id, by_employer / by_occupation a committee_id
• The output mode becomes by_size_candidate or by_state_candidate when scoped by candidate, a different row shape; itemized responses carry next_cursor, count, and count_is_approximate
• Typed errors: itemized_requires_committee_id, aggregate_requires_committee_id

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openfec_search_disbursements tool

• committee_id required in every mode: itemized (default; recipient name, state, city, and committee ID, description, purpose category, date and amount ranges, 30 rows per page), by_purpose, by_recipient, by_recipient_id
• Itemized responses carry next_cursor, count, and count_is_approximate; aggregate modes page by number

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openfec_search_expenditures tool

• itemized (default) filters by committee, candidate, support_oppose, payee, targeted office/state/district, party, is_notice (24/48-hour notices), dates, and amounts; most_recent defaults to true; 60 rows per page when scoped by committee_id, 30 otherwise
• by_candidate totals need a candidate_id or a full race scope (candidate_office=P alone, S plus candidate_office_state, H plus state and candidate_office_district), or fail as by_candidate_requires_scope

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openfec_search_coordinated_expenditures tool

• Scope by spending party committee_id, benefiting candidate_id, cycle, payee, dates, and amounts; unscoped queries span all years
• Page-based, 80 rows per page when scoped by committee_id and 25 otherwise; rows carry subordinate_committee_id, the committee the spending is attributed to

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openfec_search_filings tool

• Filters: committee_id, candidate_id, filer_name, form_type (F3, F3P, F3X, F24, F1, F2, F5), report_type, report_year, cycle, is_amended, and receipt date range; 65 rows per page
• most_recent defaults to true, hiding superseded amendments; rows carry form and report type, financial totals, and pdf_url

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openfec_lookup_elections tool

• office and an even cycle are required; Senate also needs state and House state plus district, unless a zip scopes a search
• mode: "search" (default) returns the race's candidates with totals and candidate_pcc_id / candidate_pcc_name, that cycle's principal campaign committee; mode: "summary" returns one aggregate race row
• Typed errors: cycle_must_be_even, missing_state_for_office, missing_district_for_house, summary_does_not_support_zip

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openfec_search_legal tool

• type (advisory_opinions, murs, adrs, admin_fines, statutes), query, ao_number, case_number, respondent, citations, penalty bounds, or dates; at least one is required (missing_filter), and a date bound needs type plus a date_kind that type records
• Citations, penalty bounds, respondent, ao_number, and case_number each filter only some types; one sent with a type it doesn't filter fails as filter_not_valid_for_type, and with type omitted the search returns only the types they all apply to, with a total over those types. On MURs and ADRs a citation can't be combined with case_number, respondent, a penalty bound, or an open/close date bound, which upstream would ignore; the two citation fields together match either one
• Citations take the form upstream parses — 52 U.S.C. 30104 or 11 CFR 110.1 (USC, C.F.R., §, and suffixes like 30104(g) are fine); a bare 30106 or 110.1 fails as invalid_citation instead of silently returning unfiltered results. One citation per field: upstream applies only the first citation in a value, so 52 U.S.C. 30104, 52 U.S.C. 30118 fails the same way
• Offset paging via from_hit / hits_returned, up to 200 per type within a 10,000-result window
• Results are trimmed: documents becomes document_count and document_categories, dispositions becomes disposition_count and disposition_categories, highlights stop at 3 with their <em> match markup removed and render one per line, and commission_votes shrink to a date and a 200-character action; openfec_get_legal_document returns the full record
• Each response stays under 100,000 bytes: whole results are admitted one type at a time until the next would not fit, and a page that held some back reports truncated, shown, and nextFromHit — the from_hit that continues each type, passed back with that type

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openfec_get_legal_document tool

• doc_type is the plural of a search result's document_type (mur → murs); no is that result's no field
• Returns the untrimmed record, including documents, commission_votes, and dispositions; fails as legal_document_not_found
• A record over 100,000 bytes returns its scalar fields, the arrays that fit (smallest first), and withheld — each held-back array with its entry count and size; re-call with array and offset for that array's entries while they fit, plus next_offset. An array the record lacks fails as array_not_in_record

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openfec_lookup_calendar tool

• events (default; category, one of 18 codes, and description), filing_deadlines (report_type, report_year), or election_dates (state, office, district, election_year); min_date / max_date apply in every mode, up to 100 per page
• A district filter never matches an at-large race; pair it with state

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openfec://candidate/{candidate_id} resource

• Candidate record merged with its financial totals and principal_committees (current designation P, not scoped to a cycle)
• candidate_id comes from openfec_search_candidates; fails as candidate_not_found

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openfec://committee/{committee_id} resource

• Committee record merged with its financial totals, which are absent for a committee that files no Form 3/3X/3P
• committee_id comes from openfec_search_committees; fails as committee_not_found

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openfec://election/{cycle}/{office} resource

• Presidential races (office P), with totals for the full election period
• First page only: a longer race carries truncation_notice pointing to openfec_lookup_elections, and an empty one empty_result_notice

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openfec://election/{cycle}/{office}/{state} resource

• Senate races, or an at-large House race in a single-district state (office S or H)
• Same first-page limit and notices as the presidential template

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openfec://election/{cycle}/{office}/{state}/{district} resource

• House district races (office H)
• Same first-page limit and notices as the presidential template

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openfec_money_trail prompt

• Arguments: candidate_name or candidate_id (one required), optional cycle
• Seven steps: identify the candidate, resolve the cycle's principal committee via candidate_pcc_id, then direct fundraising, independent expenditures, coordinated party spending, disbursements, and a synthesis

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openfec_campaign_analysis prompt

• Arguments: candidate_name or candidate_id (one required), optional cycle
• Seven steps: candidate overview, principal committee and per-cycle trajectory, fundraising mix, burn rate, competitive position, outside money, and an assessment

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.

OpenFEC-specific:

• Type-safe client for the OpenFEC REST API with retry and a configurable timeout; error messages have the API key stripped and HTTP failures carry recovery hints
• Cycles are even years covering two calendar years (2024 = Jan 2023 – Dec 2024); itemized Schedule A/B/E default to the current cycle when cycle is omitted, and election_full (default true) widens a race total to the full election period (4yr president, 6yr senate, 2yr house)
• Itemized contributions and disbursements scope to a committee_id, not a candidate_id. Committee designation and principal_committees reflect current designation only, so for a cycle's principal committee read candidate_pcc_id from openfec_lookup_elections
• Itemized Schedule A/B/E page with an opaque next_cursor, valid only for an otherwise-identical call; other tools page by number, and legal search by offset

Agent-friendly output:

• Effective-query echo: every tool response carries search_criteria with the post-default filters, and an empty result carries a notice on how to broaden it
• Response budget of 100,000 bytes per surface: high-volume tools cap rows per page and report truncated, shown, and cap when a page falls below the requested per_page (page-based tools also echo the applied size in pagination.per_page); legal search holds back whole results and reports nextFromHit, and a large legal document pages its arrays by offset; a single-committee query lifts that committee into one top-level committee field instead of repeating it per row
• Typed contracts: multi-mode tools echo the resolved mode and reject a filter the mode can't apply (itemized_only_filters_in_aggregate_mode, inputs_not_applicable_to_mode) instead of dropping it; every failure carries a typed reason and recovery text, and estimated totals are flagged count_is_approximate

Getting started

Public Hosted Instance

A public instance is available at https://openfec.caseyjhand.com/mcp — no installation required. Point any MCP client at it via Streamable HTTP:

{
  "mcpServers": {
    "openfec-mcp-server": {
      "type": "streamable-http",
      "url": "https://openfec.caseyjhand.com/mcp"
    }
  }
}

Self-Hosted / Local

Add the following to your MCP client configuration file.

{
  "mcpServers": {
    "openfec-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/openfec-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "FEC_API_KEY": "your-api-key"
      }
    }
  }
}

Or with npx (no Bun required):

{
  "mcpServers": {
    "openfec-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/openfec-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "FEC_API_KEY": "your-api-key"
      }
    }
  }
}

Or with Docker:

{
  "mcpServers": {
    "openfec-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": ["run", "-i", "--rm", "-e", "MCP_TRANSPORT_TYPE=stdio", "-e", "FEC_API_KEY=your-api-key", "ghcr.io/cyanheads/openfec-mcp-server:latest"]
    }
  }
}

For Streamable HTTP, set the transport and start the server:

MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 FEC_API_KEY=your-key bun run start:http
# Server listens at http://localhost:3010/mcp

Prerequisites

• Bun v1.4.0 or higher (or Node.js v24+).
• Optional: a free OpenFEC API key raises the rate limit from 30 to 1,000 requests per hour over the default DEMO_KEY.

Installation

1. Clone the repository:

git clone https://github.com/cyanheads/openfec-mcp-server.git

2. Navigate into the directory:

cd openfec-mcp-server

3. Install dependencies:

bun install

4. Configure environment:

cp .env.example .env
# edit .env and set FEC_API_KEY (optional)

Configuration

Variable	Description	Default
FEC_API_KEY	OpenFEC API key from api.data.gov. DEMO_KEY allows 30 req/hr; your own key allows 1,000.	DEMO_KEY
FEC_BASE_URL	OpenFEC API base URL.	https://api.open.fec.gov/v1
FEC_MAX_RETRIES	Retry attempts for failed API requests.	3
FEC_REQUEST_TIMEOUT	Per-request timeout, in ms.	30000
MCP_TRANSPORT_TYPE	Transport: stdio or http.	stdio
MCP_HTTP_PORT	HTTP server port.	3010
MCP_SESSION_MODE	HTTP session mode: stateless, stateful, or auto. Overrides the stateless mode the server declares.	stateless
MCP_AUTH_MODE	Authentication: none, jwt, or oauth.	none
MCP_LOG_LEVEL	Log level (debug, info, warning, error, etc.).	info
LOGS_DIR	Directory for log files (Node.js only).	<project-root>/logs
STORAGE_PROVIDER_TYPE	Storage backend: in-memory, filesystem, supabase, cloudflare-kv/r2/d1.	in-memory
OTEL_ENABLED	Enable OpenTelemetry.	false

See .env.example for the full list of optional overrides.

Running the server

Local development

• Build and run:

  bun run rebuild
  bun run start:stdio   # or start:http
  

• Run checks and tests:

  bun run devcheck      # Lint, format, typecheck, security audit
  bun run test          # Vitest test suite
  bun run lint:mcp      # Validate MCP definitions against spec
  

Docker

docker build -t openfec-mcp-server .
docker run --rm -e FEC_API_KEY=your-key -p 3010:3010 openfec-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/openfec-mcp-server. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.

Project structure

Directory	Purpose
src/index.ts	createApp() entry point — registers tools/resources/prompts and inits the OpenFEC service.
src/config	Server-specific environment variable parsing and validation with Zod.
src/mcp-server/tools	Tool definitions (*.tool.ts), with shared validators and formatters in definitions/utils/.
src/mcp-server/resources	Resource definitions (*.resource.ts). Candidate, committee, and three election-race templates.
src/mcp-server/prompts	Prompt definitions (*.prompt.ts). Money trail and campaign analysis.
src/services/openfec	OpenFEC API client and domain types.
tests/	Unit and integration tests, mirroring the src/ structure.
scripts/	Build, clean, devcheck, tree, changelog, and lint scripts.
docs/	Design notes and the OpenFEC OpenAPI spec.

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 barrels at src/mcp-server/*/definitions/index.ts
• Wrap the OpenFEC API: validate raw → normalize to domain type → return the output schema; never fabricate fields the upstream response omitted

Contributing

Issues are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

License

Apache-2.0 — see LICENSE for details.