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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds the useful fact that the id prefix determines which record type is returned, but says nothing about what happens on an unknown or malformed id, or about the size/shape of the returned record.

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?

A single sentence that front-loads the verb and resource and packs the id-format detail into a parenthetical. No filler, nothing wasted.

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 one-parameter read tool whose annotations already establish safety, the definition covers the input format and the general return ('full record'). With no output schema the agent still cannot know the record's fields, but nothing essential for invoking the tool correctly is missing.

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%, so the bare 'id' string parameter carries no meaning on its own; the description compensates by documenting the accepted id forms (model:<slug>, gecko-test:<slug>, scorecard). That is real semantic value beyond the schema, though it omits format constraints for each prefix.

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?

States a specific verb ('Fetch') and resource ('the full record') and clarifies it operates on an id produced by search, covering model, gecko-test and scorecard records. It implicitly spans the typed siblings get_model/get_gecko_test/get_scorecard but never names them, so differentiation is inferred rather than stated.

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 ties usage to ids 'returned by search', which implies the workflow (search first, then fetch), but it never says when to prefer this generic fetch over the typed siblings get_model, get_gecko_test or get_scorecard. Usage is implied, not prescribed.

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