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

Annotations already declare readOnly/idempotent/non-destructive/open-world, so the safety profile is covered. The description adds value beyond that: the authoritative source (JPO public trademark register) and the fact that a status code and mark type are returned, telling the agent what kind of result to expect.

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-loaded single sentence plus a source line and examples — efficient and scannable. The enumerated return fields are partly redundant given a declared output schema, costing some space.

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 annotations, a fully described 2-param schema, and an output schema, the description covers essentially everything an agent needs. The one residual gap is the 'status code' — it never says what the code domain looks like, which matters for interpreting the lookup.

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% and the enum/default for number_type are already documented, so the baseline is 3. The description's number examples reinforce the two accepted formats but add no semantics the schema lacks (e.g., it does not explain what happens if number_type mismatches the format).

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 ('Look up') and resource ('Japanese trademark') plus the access key (application or registration number) and enumerates what comes back. The trademark-vs-patent distinction separates it cleanly from jp_patent_status; an agent can tell them apart from the description alone.

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?

Provides concrete example identifiers ('application 2020-000001, registration 6316886'), which implies the usage context, but never states when to choose this over jp_patent_status or another lookup tool, nor any prerequisites or failure conditions.

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