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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the bar is lower. The description adds useful context by specifying the election cycle, filterable dimensions, and return content (campaign website, social media, FEC data, position/speech counts), which goes beyond the annotations. It does not disclose pagination behavior, but that is not a major gap given the safety hints.

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?

Two concise sentences front-load the core purpose and filters, followed by return data. Every sentence contributes useful information with no redundancy or fluff.

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?

With no output schema, the description partially compensates by listing return content. It covers key filter dimensions and the election cycle, but omits pagination details and the exact meaning of 'position and speech counts'. Given the read-only nature and rich annotations, this is sufficient for a list tool.

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 baseline is 3. The description adds marginal value by summarizing filters (state, office, party, has_url) and enumerating office values, but this largely restates schema. It does not provide additional parameter semantics beyond the schema descriptions.

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?

The description clearly states the tool returns registered federal candidates for the 2026 election cycle, with filtering by state, office, party, and URL presence. It distinguishes from siblings by its specific focus on federal candidates and the data returned (campaign website, FEC data, counts), though it lacks an explicit verb like 'list' or 'get'.

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?

The description implies usage through its filter options and return fields, but it does not explicitly state when to use this tool versus alternatives like politics_candidate_feed or politics_search. No exclusions or alternative tool recommendations are provided, so guidance is minimal.

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