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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: the catalogue's scale (95,403 items), that it is name-based lookup against public documents, and that it returns existence plus an evidence URL. It does not discuss rate limits or auth, which is the only gap.

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?

Content is front-loaded with what is searched and what is returned, and the routing clauses come last. The bilingual duplication doubles the length, which is defensible for a Japanese-domain tool but is not maximally concise.

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?

An output schema exists, so return-value documentation is not required, yet the description still conveys the essential return shape (existence flag plus evidence URL). Purpose, scope, and routing to sibling tools are all covered, leaving nothing an agent needs before calling it.

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, category and limit are already documented in the schema (including Japanese example and 1-50 bounds). The description implies name-based lookup and references the category filter only obliquely via a sibling tool's parameter, adding little beyond the schema. Baseline 3 is appropriate.

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 (search) and resource (JCCDB item catalogue of 95,403 line items within 526,128 records), plus what it returns: whether a named material/product/labor item exists in a public document with an evidence URL. It is immediately distinguishable from siblings like get_jccdb_observations and search_cost_category.

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?

Explicit routing: 'materials that are not renovation work categories use this one', and '地域・時点・価格は get_jccdb_observations' names the alternative and the condition that selects it. An agent knows when to pick this tool versus the observation/price siblings.

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