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

The annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the description needs only to add behavioral context. It does so by identifying the exact source portal (官公需情報ポータルサイト), clarifying that organization matching is partial, and noting the optional full-text return mode. This adds useful transparency beyond the annotation flags without contradicting them.

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?

The description is a single, well-structured sentence that front-loads the core action and resource, then adds source attribution and filter options. The Japanese examples and portal name are relevant, and there is no redundant filler or restating of annotations.

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 read-only lookup tool with a fully documented schema, the description supplies enough context: required organization name, optional narrowing filters, source data, and partial-match semantics. The main gap is not describing the return format or sample output, but this is mitigated by the full_text parameter and the absence of an output schema; an explicit note about pagination/limit behavior would round it out.

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?

The input schema already covers 100% of parameters with descriptions, so the baseline is 3. The description adds some context by explaining that organization_name is a partial Japanese match and by naming the filter dimensions, but it largely duplicates what the schema already provides. It does not contribute material new semantics for the individual parameters.

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?

The description opens with a specific verb and resource: 'List Japanese government tender notices published by a named buyer.' It further clarifies the matching basis (partial organization name) and gives concrete Japanese examples, making the tool's purpose unmistakable and distinguishing it from sibling tender tools like japan_tenders_by_prefecture.

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?

The description clearly conveys when to use this tool: when organizing by a named buyer such as a ministry or city. It also mentions optional filters for category, keyword, and date range. It does not explicitly name alternative sibling tools or state when not to use them, but the scope is specific enough that the intended use case is well understood.

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