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 safety profile is disclosed. The description adds the useful behavioral note 'Uses metered access when findings exist,' which is not present in the annotations. A touch more detail about return format would push this higher, but the bar is met.

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?

Three sentences, each earning its place: the first states the purpose, the second gives usage instructions, and the third points to an alternative tool. No redundancy, perfectly sized.

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 read-only scan tool with 0 required parameters and an output schema, the description covers the core behavior (deprecations, sunset dates, replacements), filter usage, and the closest alternative. The only minor gap is what returns look like, but the output schema presumably covers that, so this is sufficiently complete.

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 100% with both parameters well described. The description adds operational semantics beyond the schema: 'Omit filters for the catalogue-wide view, pass service to limit one API' and 'add endpoints to check selected paths,' which helps an agent reason about parameter combination rather than just individual fields.

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 starts with a specific verb and resource: 'Scan publisher specifications for deprecated endpoints or parameters, sunset dates, and replacement operations.' It clearly states what the tool does and what it finds, and differentiates from the sibling 'factreason_api_breaking_changes' by naming it explicitly.

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?

Explicit guidance is given: 'Omit filters for the catalogue-wide view, pass service to limit one API, and add endpoints to check selected paths.' It also tells the agent when NOT to use this tool and what to use instead: 'Use factreason_api_breaking_changes for broader version-to-version changes.'

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