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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the description does not need to repeat safety properties. It adds valuable behavioral context about the shape of the result, including FEC distinct-person counts and the meaning of incumbent_note for open seats, though it does not mention pagination or output ordering.

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 sentences, front-loaded with the core scope and then the operational routing tip. Every clause earns its place, and nothing is repeated from the schema.

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 an output schema present, the description need not explain return values, but it still helpfully clarifies what incumbent_note means. Together with rich annotations and fully documented parameters, it is nearly complete; the only minor omission is the office filter, which is covered in the schema.

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 schema already defines state, cycle, and office, including that cycle defaults to 2026 and office restricts to house or senate. The description reinforces the state-and-cycle scoping but does not mention the office filter or add syntax or format details beyond what the schema provides, so baseline 3 is appropriate.

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 states a specific verb and resource ('Every federal race in a state for a cycle') and enumerates exactly what is returned (Senate seat and each House district, FEC registration counts, incumbent and incumbent_note). It clearly distinguishes itself from race_matchup by positioning itself as the discovery tool for district numbers.

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?

It explicitly tells the agent when to use the tool: to find the district number before calling race_matchup. This names both the alternative sibling and the precondition that selects this tool over that one.

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