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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuine value by scoping the payload (summary only, body excluded), but it says nothing about the caching semantics implied by the refresh parameter, nor about rate limits or staleness — a notable omission for an open-world read tool.

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?

A single front-loaded sentence that lists the returned fields, followed by a short exclusion clause. No filler, no repetition of the title, and the most important scoping fact is stated up front.

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-shape detail is largely redundant, and the description is complete about what is and is not returned. But for a two-parameter tool with 0% schema coverage, the unexplained refresh flag and the absence of any usage or prerequisite context leave real gaps.

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 0%, so the description carries the full burden for two parameters, and it explains neither. subsidy_id is only inferable from context, and refresh — a boolean that clearly controls cache bypass — is completely undocumented in both schema and description.

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 (返す) and resource (補助金の概要) and enumerates exactly which fields are returned (公募回次・対象地域・締切・上限額・補助率・添付文書名とページ数). The negative clause 本文は返さない separates it from body-text retrieval tools like get_guideline_pages, though no sibling is named explicitly.

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 exclusion 本文は返さない implicitly tells the agent when to look elsewhere for full text, and the 'detail for a given subsidy' framing implies use after a search. However there is no explicit when-to-use statement, no prerequisite (e.g., needing a subsidy_id from search_subsidies), and no named alternative tool.

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