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

Annotations already declare read-only/open-world safety, so the description adds useful data-quality context: filters combine with AND, roughly a third of rows carry an FEC id, only sitting members carry a Bioguide id, and people_id is populated only when a voting record exists. It does not cover pagination totals or result ordering, but the behavioral context it does add is substantive.

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

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

The description is dense and front-loaded with purpose, then routing hints. Every clause carries information, though the middle sentences about FEC and Bioguide ids are somewhat compressed.

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

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

No output schema exists, so the description must explain return values. It describes key row fields (fec_id, bioguide, people_id) and coverage, but omits the candidate name/id field and pagination behavior, leaving minor gaps for an agent forming expectations about results.

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

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

Schema coverage is 100%, so the baseline is 3. The description adds meaning beyond the schema by explaining that filters combine with AND and by clarifying when fec_id and bioguide will be non-null, which helps the agent interpret filter behavior.

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

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

States a specific verb and resource ('Search the election-candidate directory... people running for office') plus the underlying endpoint. This clearly separates it from siblings like list_legislators and get_candidate.

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

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

Explicitly routes the agent: use get_candidate for the full record via candidate id, and get_legislator / get_legislator_scorecard for voting history via people_id. It states scope (STATE and federal candidates) but does not explicitly contrast with list_legislators.

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