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

Annotations already declare readOnly, idempotent and closed-world, so the safety profile is covered. The description adds genuinely useful behavior beyond them: conjunctive token matching ('Every word must match') and the result ordering ('Newest model years first'), both of which affect how an agent forms and interprets queries.

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 short sentences, front-loaded with the core action, and each clause carries non-redundant information (matching rule, return fields, sort order). No filler.

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 two-parameter read-only search with full schema coverage and no output schema, the description supplies what is needed: matching semantics, ordering, and the returned fields. It could be complete at 5 with a note on empty-result behavior or the limit interaction, but nothing essential 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 coverage is 100%, so the baseline is 3. The description still adds meaning beyond the schema by clarifying the query semantics — all tokens must match — which is not expressible in a plain string schema and directly affects how the "toyota rav4" example behaves.

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 names a specific verb and resource ('Search the priced catalogue') and states the matching dimensions (make, model, trim, year) plus the return payload ('slug and true monthly cost'). It is clear without needing the schema, though it does not explicitly differentiate itself from siblings like get_true_cost or cost_index.

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?

There is no explicit when-to-use guidance and no mention of the sibling tools (compare_true_cost, cost_index, get_true_cost), so an agent must infer that this is the entry-point search. The matching constraint ('Every word must match') is a usage rule but not routing guidance.

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