io.github.cyanheads/openstates-mcp-server

Official

by cyanheads · TypeScript

Search bills, legislators, committees, and events across all 50 US states, DC, and Puerto Rico.

Search US state bills, legislators, committees, and events.

Topics

aibunlegislationmcpmcp-servermodel-context-protocolopenstatesstate-legislaturebillslegislatorstypescriptopen-statescyanheads

README.md15 KBView on GitHub

<div align="center"> <h1>@cyanheads/openstates-mcp-server</h1> <p><b>Search bills, legislators, committees, and events across all 50 US states, DC, and Puerto Rico via MCP. STDIO or Streamable HTTP.</b> <div>10 Tools • 1 Resource • 2 Prompts</div> </p> </div> <div align="center">

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

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Tools

10 tools covering the full Open States v3 API surface — bills, legislators, committees, events, and jurisdictions:

Tool	Description
`openstates_search_bills`	Search state legislative bills across all covered US jurisdictions with full-text search, jurisdiction/session filtering, subject tags, and sponsor lookups
`openstates_get_bill`	Fetch full detail for a specific bill by OCD ID or three-part path (jurisdiction + session + bill_id)
`openstates_search_people`	Search state legislators and officials by name, jurisdiction, chamber, district, or party
`openstates_get_legislators_by_location`	Find all legislators representing a geographic coordinate (latitude/longitude)
`openstates_search_committees`	List committees for a jurisdiction (experimental — not all states have coverage)
`openstates_get_committee`	Fetch committee detail by OCD organization ID, with optional membership roster
`openstates_search_events`	Search hearings, floor sessions, and committee meetings (experimental)
`openstates_get_event`	Fetch full event detail including agenda, participants, and media links
`openstates_list_jurisdictions`	List all 52 jurisdictions covered by Open States with session identifiers and coverage metadata
`openstates_get_jurisdiction`	Fetch full metadata for a specific jurisdiction including all legislative sessions and their identifiers

`openstates_search_bills`

Search state legislative bills with rich filtering and inline related data.

Full-text search across bill titles, abstracts, and text (q)
Filter by jurisdiction (state name, two-letter abbreviation, or OCD-ID), session, chamber, classification, subject tags, and sponsor
Sort by latest action, first action, or update time — use sort=latest_action_desc for bills currently moving through the legislature
include parameter requests sponsorships, actions, votes, abstracts, versions, and related bills inline — eliminates follow-up openstates_get_bill calls for most research workflows
action_since and updated_since date filters for change-tracking
Pagination up to 20 results per page
Empty-result recovery: echoes applied filters and suggests how to broaden

`openstates_get_bill`

Fetch complete bill detail by OCD ID or path lookup.

Two lookup modes: openstates_id (OCD bill ID from search results, preferred) or the three-part path jurisdiction + session + bill_id
Accepts bill identifiers in legislature format (e.g., HB 1000, SB 42)
include=votes returns full vote tallies and per-legislator positions
include=versions,documents provides links to bill text and fiscal notes
Sponsors carry linked person records (OCD person ID + name) when available

`openstates_search_people`

Search legislators and officials by name, jurisdiction, chamber, or district.

Case-insensitive substring matching on name
org_classification targets a specific chamber: upper (Senate), lower (House/Assembly), legislature (all), executive (governors and executive officials)
include=offices returns phone, fax, and mailing address
include=links returns website and social media links
Strongly recommended to provide jurisdiction — omitting it returns legislators across all states

`openstates_get_legislators_by_location`

Find all state legislators representing a geographic coordinate.

Pass decimal-degree latitude/longitude to get state senators and representatives for that location
Useful for constituent-to-representative matching, address-based policy research, and electoral boundary analysis
Does not geocode addresses — the caller must provide coordinates
Returns a coverage note when no legislators are found (e.g., coordinates outside US boundaries)

`openstates_list_jurisdictions` and `openstates_get_jurisdiction`

Discover and look up jurisdiction coverage metadata.

openstates_list_jurisdictions returns all 52 jurisdictions (50 states + DC + Puerto Rico) in a single call with per_page=52 (the default)
include=legislative_sessions returns all historical and current session identifiers — required before filtering bill searches by session, since formats vary widely by state (e.g., 2025, 2025-2026, 2025rs, 2025s1)
openstates_get_jurisdiction fetches one jurisdiction by OCD-ID, state name, or two-letter abbreviation

Committee and event tools (experimental)

openstates_search_committees, openstates_get_committee, openstates_search_events, and openstates_get_event are experimental — Open States is actively working to restore committee support and most states do not publish event data. Empty results may indicate the state lacks data, not that no committees or events exist. All four tools include a coverage_note in their output documenting this limitation.

Resources and prompts

Type	Name	Description
Resource	`openstates://jurisdiction/{jurisdiction_id}`	Jurisdiction metadata including current sessions, coverage dates, and bill/people update timestamps
Prompt	`openstates_bill_research`	Structured framework for analyzing a state bill: summary, sponsors, committee referrals, action timeline, vote record, and related legislation
Prompt	`openstates_legislator_profile`	Research framework for profiling a legislator: sponsored bills, committee assignments, voting record, and contact details

All resource data is also reachable via tools. Use openstates_get_jurisdiction for programmatic jurisdiction lookups; the resource is useful for injecting jurisdiction context as stable reference material.

Features

Built on @cyanheads/mcp-ts-core:

Declarative tool, resource, and prompt definitions — single file per primitive, framework handles registration and validation
Unified error handling — handlers throw, framework catches, classifies, and formats
Pluggable auth: none, jwt, oauth
Swappable storage backends: in-memory, filesystem, Supabase, Cloudflare KV/R2/D1
Structured logging with optional OpenTelemetry tracing
STDIO and Streamable HTTP transports

Open States-specific:

Full Open States v3 API coverage: bills, people, committees, events, and jurisdictions
Dual lookup modes on bill and committee fetchers (OCD ID or structured path)
Geo-based legislator lookup via the Open States people-by-geo endpoint
Server-level instructions prime the agent with session discovery workflow and include parameter strategy before any tool calls

Agent-friendly output:

Empty-result recovery: tools echo the applied filters and suggest how to broaden when no results are returned
Experimental coverage notes on committee and event tools — agents can surface these to users rather than returning silent empty results
include parameter pattern across all search and get tools — avoids N+1 follow-up calls for common research workflows (e.g., include=sponsorships,actions on openstates_search_bills)

Getting started

Requires an Open States API key — register free at open.pluralpolicy.com.

Add the following to your MCP client configuration file:

json

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

Or with npx (no Bun required):

json

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

Or with Docker:

json

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

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

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

Prerequisites

Bun v1.3.0 or higher (or Node.js v24+).
An Open States API key — register free at open.pluralpolicy.com.

Installation

Clone the repository:

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

Navigate into the directory:

cd openstates-mcp-server

Install dependencies:

bun install

Configure environment:

cp .env.example .env
# edit .env and set OPENSTATES_API_KEY

Configuration

All configuration is validated at startup via Zod schemas in src/config/server-config.ts. Key environment variables:

Variable	Description	Default
`OPENSTATES_API_KEY`	Required. Open States API key from open.pluralpolicy.com.	—
`OPENSTATES_API_BASE_URL`	Open States API base URL.	`https://v3.openstates.org`
`MCP_TRANSPORT_TYPE`	Transport: `stdio` or `http`.	`stdio`
`MCP_HTTP_PORT`	HTTP server port.	`3010`
`MCP_HTTP_ENDPOINT_PATH`	HTTP endpoint path.	`/mcp`
`MCP_PUBLIC_URL`	Public origin override for TLS-terminating reverse-proxy deployments.	none
`MCP_AUTH_MODE`	Auth mode: `none`, `jwt`, or `oauth`.	`none`
`MCP_LOG_LEVEL`	Log level (`debug`, `info`, `notice`, `warning`, `error`).	`info`
`MCP_GC_PRESSURE_INTERVAL_MS`	Opt-in Bun-only forced-GC interval (ms). Try `60000` if heap grows under sustained HTTP load.	`0` (disabled)
`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 instrumentation.	`false`

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

Running the server

Local development

Build and run the production version:

# One-time build
bun run rebuild

# Run the built server
bun run start:stdio
# or
bun run start:http

Run checks and tests:

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

Docker

docker build -t openstates-mcp-server .
docker run --rm -e OPENSTATES_API_KEY=your-key -e MCP_TRANSPORT_TYPE=http -p 3010:3010 openstates-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/openstates-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 Open States service.
`src/config`	Server-specific environment variable parsing and validation with Zod.
`src/mcp-server/tools`	Tool definitions (`*.tool.ts`). Ten tools across bills, people, committees, events, and jurisdictions.
`src/mcp-server/resources`	Resource definitions. Jurisdiction metadata resource.
`src/mcp-server/prompts`	Prompt definitions. Bill research and legislator profile prompts.
`src/services/openstates`	Open States API v3 service layer — HTTP client, request handling, domain types.
`tests/`	Unit and integration tests mirroring `src/`.

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 request-scoped logging, ctx.state for tenant-scoped storage
Register new tools and resources via the arrays in src/index.ts
Wrap external API calls: validate raw → normalize to domain type → return output schema; never fabricate missing fields

Contributing

Issues and pull requests are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

License

Apache-2.0 — see LICENSE for details.

Install

Configuration

Environment variables

OPENSTATES_API_KEYrequired

Open States API key from open.pluralpolicy.com. Required to make any API requests.

MCP_LOG_LEVELdefault info

Sets the minimum log level for output (e.g., 'debug', 'info', 'warn').

MCP_HTTP_HOSTdefault 127.0.0.1

The hostname for the HTTP server.

MCP_HTTP_PORTdefault 3010

The port to run the HTTP server on.

MCP_HTTP_ENDPOINT_PATHdefault /mcp

The endpoint path for the MCP server.

MCP_AUTH_MODEdefault none

Authentication mode to use: 'none', 'jwt', or 'oauth'.

claude_desktop_config.json

{
  "mcpServers": {
    "openstates-mcp-server": {
      "command": "npx",
      "args": [
        "-y",
        "@cyanheads/openstates-mcp-server@0.1.10",
        "run",
        "start:stdio"
      ],
      "env": {
        "OPENSTATES_API_KEY": "<YOUR_OPENSTATES_API_KEY>",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

Topics

Tools

openstates_search_bills

openstates_get_bill

openstates_search_people

openstates_get_legislators_by_location

openstates_list_jurisdictions and openstates_get_jurisdiction

Committee and event tools (experimental)

Resources and prompts

Features

Getting started

Prerequisites

Installation

Configuration

Running the server

Local development

Docker

Project structure

Development guide

Contributing

License

Install

Configuration

`openstates_search_bills`

`openstates_get_bill`

`openstates_search_people`

`openstates_get_legislators_by_location`

`openstates_list_jurisdictions` and `openstates_get_jurisdiction`