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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds useful domain context (bilingual names, EDINET entity codes) but says nothing about error/not-found behavior or whether results are cached or sourced from EDINET.

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?

Two sentences, and the second largely repeats the first's field list (names, entity code, ticker, industry). The EDINET hint is the only new information in sentence two, so the definition is roughly 40% redundant.

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 no output schema, the description does the right job of enumerating return fields and noting bilingual output. Only gap is failure modes and how lookups resolve ambiguous names (e.g., 'name' vs 'simple_name').

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 id_type enum values are fully documented in the schema, so this is baseline 3. The description's 'by any identifier' and the EDINET note add only marginal meaning beyond the schema.

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 ('Return the profile of one Japanese listed company') and names the fields returned. It implicitly separates a single-profile lookup from sibling search/screen tools by emphasizing 'one' company, but never names an alternative 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 phrase 'by any identifier' hints at flexible input, but there is no explicit when-to-use guidance, no mention of when to use search_companies or screen_companies instead, and no note on what happens if the company is not found.

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