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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description's job is added context — and it delivers: corpus scope (~225 decisions), backing infrastructure (same Qdrant hybrid search), and the fact that each result spans the full thread (referring order, binding answer, final judgment). No contradiction with 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?

Front-loads the scope and the routing rule, and each sentence carries information. It is somewhat dense with repeated parentheticals (統一法律見解／法律見解歧異 restated in the schema query field), which costs a point but does not obscure the message.

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 search tool with no output schema, the description supplies everything needed to call and interpret it correctly: scope, corpus size, the semantic shape of returned results, and the sibling alternative. Nothing material 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%, so query, limit, and case_types are already well documented in the schema — including the caveat not to infer case_type from query wording. The description adds no parameter-level syntax or format detail beyond that, so the baseline of 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 (search Grand Chamber rulings) and immediately scopes it to Taiwan's 大法庭 mechanism for resolving divergent interpretations. It names the sibling it is not (search_decisions) and the distinguishing question type, so an agent can route without opening either 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 gives the selection rule: use this instead of search_decisions when the question is about which legal interpretation prevails on a disputed point, not an ordinary fact-pattern search. The when-not condition is stated, not inferred.

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