Keyword search over plan clauses

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

Annotations already cover safety (readOnlyHint=true, openWorldHint=false), and the description adds real behavioral context beyond them: lexical rather than semantic matching, a hard cap of the top 3 clauses, the returned fields, and a privacy guarantee that member data is never returned. It does not describe empty-result behavior or how scoring ranks ties, which keeps it below a 5.

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 mechanism, then the return contract, then the alternative-tool routing. No filler; every sentence carries distinct information.

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?

There is no output schema, but the description compensates by naming the exact returned fields and the top-3 cap, and it bounds scope with the no-member-data guarantee. For a two-parameter read-only search, nothing an agent needs to call it 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 100% — the query parameter includes a format example and plan_id carries an enum plus its scoping meaning — so the schema already does the work. The description adds no parameter-level detail (e.g., whether plan_id affects scoring or just filtering), 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?

States a specific verb and resource ("keyword retrieval over the clauses of the synthetic plan documents") and immediately disambiguates the mechanism ("lexical scoring, not semantic search"), which separates it from a semantic-search sibling and from get_plan_clause. An agent can tell what this tool does without opening the schema.

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?

Explicitly routes: "Use it for general plan questions, then get_plan_clause for the full text" — a clear when-to-use plus a named alternative for the follow-up step. It lacks an explicit exclusion (e.g., when to prefer verify_benefits_batch for batch eligibility checks), so it falls short of a 5.

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