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

With no annotations, the description carries the full burden and does substantial work: it discloses the auth requirement (API key, Authorization: Bearer), the cost model (5 credits/call, $0.0053–$0.02 per credit), and the proxied POST endpoint. It also clarifies a subtle semantic ('undetermined is not a pass'). It omits rate limits, error/retry behavior, and pagination semantics.

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?

Front-loaded with the core question and return shape, then auth, cost, endpoint and the sibling alternative. Dense and nearly every sentence earns its place, though the pricing URL and proxy detail make it slightly cluttered.

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?

For a 7-parameter tool with nested objects and no output schema, it covers auth, cost, endpoint and verdict semantics well, and describes the per-model/per-platform return shape. It leaves the paging/filter parameters and the policy sub-fields (residency, commercial_use) unexplained, so an agent would still have to guess at several arguments.

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 description coverage is 0% across 7 parameters, one of which is a nested policy object, so the description must compensate and largely does not. It indirectly explains the verdict vocabulary ('pass, fail or undetermined', matching the verdicts enum) and names the licence/origin dimensions of the policy object, but limit, offset, require_no_undetermined, models and platforms are never explained.

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 opening question plus the explicit statement of what is returned ('pass, fail or undetermined per model/platform for licence, origin and data handling') gives a specific verb+resource and scope. It also differentiates itself from the sibling 'decide' by stating 'It doesn't choose a model'.

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 names an alternative tool and the condition that selects it ('use decide among passing rows'), which is real routing guidance. It does not, however, explain when to apply the filter parameters (models, platforms, verdicts) or when other siblings such as compare_models or rank would be more appropriate.

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