Skip to main content
Glama
lzinga

US Government Open Data MCP

congress_house_votes

Read-only

Retrieve House roll call vote results with party breakdown. Supports votes from 1990 to present by congress, session, year, or vote number.

Instructions

Get House of Representatives roll call vote results with member-level party breakdown. Primary source: Congress.gov API (118th-119th Congress); falls back to clerk.house.gov XML for older congresses. Coverage: 1990 to present. Use year param for historical votes. Cross-reference with: congress_senate_votes (same bill's Senate vote), FEC (congress_member donors via fec_candidate_financials), lobbying_search (who lobbied on the bill), FRED (economic impact 1-3 years after passage). For Senate votes, use congress_senate_votes.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
congressNoCongress number (default: current). Used with session to determine year.
sessionNoSession (1 or 2). Default: current session
yearNoCalendar year (e.g. 2024). Overrides congress+session if provided.
vote_numberNoSpecific roll call vote number. Omit to list recent votes.
limitNoMax results when listing votes (default: 20)
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate readOnlyHint=true. The description adds valuable behavioral context: it uses two data sources (Congress.gov API for recent, clerk.house.gov for older), covers 1990-present, and includes fallback behavior. This goes beyond annotations, though it could mention pagination or rate limits.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise (two main sentences plus cross-references) and front-loaded with the primary purpose. The cross-references are comprehensive but not verbose. Every sentence adds value, though the list of cross-references could be slightly trimmed.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (5 parameters, multiple sources, no output schema), the description covers key aspects: data sources, coverage, parameter behavior, and related tools. It doesn't detail the return format or pagination, but for a read-only vote tool, this is sufficient.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage for all 5 parameters. The description adds the context that the year parameter overrides congress+session and that vote_number can be omitted to list recent votes, which slightly enhances meaning, but the schema already covers the basics. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool gets House roll call votes with party breakdown, and distinguishes it from congress_senate_votes. It specifies the source and coverage, making the purpose unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit guidance: when to use the year parameter, cross-references to related tools for deeper analysis, and explicitly states to use congress_senate_votes for Senate votes. This leaves no ambiguity about when to use this tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/lzinga/us-gov-open-data-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server