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

Annotations cover safety (readOnly, idempotent, non-destructive), and the description adds substantive behavior beyond them: the ranking mechanism (hybrid semantic + keyword, reranked), the non-exhaustive result contract, and the exact court-tier coverage boundary. These are the traits an agent most needs to know to avoid treating results as a complete match set.

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 purpose and scope in the first two sentences, then routing rules, then the read-in-full pointer. It is dense but every clause carries routing or behavioral information; nothing is 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?

No output schema exists, yet the description tells the agent what results look like (relevant ranked subset, not all matches) and how to continue reading one (get_decision_details by jid). Combined with full schema coverage and annotations, an agent has everything needed to call and follow up correctly.

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 all three parameters are already documented, including the case_types caveat about not inferring filters from query wording. The description adds essentially no parameter-level detail beyond the schema (e.g., no guidance on sensible limit values or query phrasing), 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 ('Search Taiwan (ROC) court decisions') and immediately narrows the scope to a named apex-tier set of courts, explicitly excluding district and high court decisions. This lets an agent separate it from search_decisions_exact and search_law without opening any 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?

Gives concrete trigger questions ('how have courts ruled on X'), states the negative condition ('it returns the most relevant decisions, not every match'), and names three alternatives with the exact condition that selects each (search_decisions_exact for exhaustive literal matches/counts, search_grand_chamber_decisions for divergent-panel interpretation questions, search_law for statutes), plus the follow-up get_decision_details.

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