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

Annotations already declare the full safety profile (readOnly, idempotent, non-open-world, non-destructive), so the description isn't burdened with disclosing safety. It adds the 'typeahead' behavioral nature and states return content (resource links to trips), which is modest added value beyond the schema and 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 tight sentences, front-loaded with the core action and scope, and the return behavior. Every clause earns its place with no redundancy.

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?

With an output schema covering return values and annotations covering the safety profile, the description needs only to establish intent and scope, which it does. It is nearly complete, though the distinction from the generic 'search' and 'trips_list' siblings could be sharper.

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 a single 'query' parameter already documented ('Search text; may be empty.'). The description adds no syntax, format, or matching semantics beyond what the schema provides, so the baseline 3 applies.

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 gives a specific verb (typeahead search), resource (the user's Tineo trips), and a narrowing scope (for composer @-mentions), which is far more informative than the title 'Find Trips to Mention'. It does not explicitly name a sibling it differs from, so it falls short of a 5 despite being clear.

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 phrase 'for composer @-mentions' implies the usage context (populating a mention autocomplete), but there is no explicit when-to-use guidance, no when-not, and no alternative named among the many sibling search/list tools. Usage is implied rather than stated.

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