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

With no annotations, the description takes full burden. It discloses tolerance for ID variations (dots vs dashes, suffixes, prefixes) and what it checks (scheduled retirements, past retirements, breaking changes). However, it does not explicitly state it is read-only or describe failure modes.

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, front-loaded with purpose, no filler. Every sentence adds value: purpose, behavior, usage. Excellent conciseness.

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 covers purpose, matching logic, and usage. Lacks explicit output description (no output schema), but for a check tool with one array parameter, it is adequately complete for an agent to understand and invoke.

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% with an example. The description adds significant semantic meaning by explaining the purpose of the parameter and the matching logic, going beyond the schema's basic type and example.

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 checks model IDs against retirement records, with a friendly opener 'Is my stack okay?' The verb 'Check' and resource are explicit, and it distinguishes from siblings like list_deprecations by focusing on specific models.

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 advises calling 'at startup or in CI with the models you depend on,' providing clear usage context. It does not explicitly exclude alternatives or contrast with siblings, but the guidance is strong.

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