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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds useful behavioral context beyond that by explaining what each result category returns (actual value for wrong, real season coverage for unverifiable). This is helpful and consistent with the annotations.

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 with no filler: the first states the operation, the second explains return categories and input constraint. Key information is front-loaded, and every sentence adds value.

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?

The description explains the outcome categories well despite no output schema, and the schema covers optional season and entity_kind constraints. A small gap is the absence of an example or a fuller definition of Muffed's verified panel, but the tool is still callable correctly from the description plus 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?

With schema_description_coverage at 0%, the description needed to compensate by explaining the meaning of metric, entity, and value, but it only says 'structured fields only, not sentences'. The field names and enum are present in the schema, but the description does not clarify how to populate the required claim object or what counts as a valid metric/entity.

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 verb 'Checks' and the resource 'structured claims against Muffed's verified panel', and further specifies the three possible outcomes. It is clear, though it does not explicitly name sibling tools or contrast itself with run_stat_query/query_stat_leaders, so it stops short of full sibling differentiation.

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 sentence 'Takes structured fields only, not sentences' gives a concrete usage boundary and tells an agent what input form is acceptable. It does not, however, point to an alternative tool for free-text claims or explain when a sibling would be preferred.

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