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

Annotations declare readOnlyHint and openWorldHint, which are consistent with the description. The description adds substantial behavioral context beyond annotations: rate limit (~10 req/s), price ($0.003 USDC per successful call), payment methods (x402 on Base, Solana or Arc), and the fact that failed calls are not charged.

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 front-loaded with purpose and is generally efficient. However, the long enumeration of return fields is partly redundant because an output schema exists, slightly reducing conciseness.

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 paid external search tool, the description covers purpose, data source, rate limit, cost, payment details, and charging policy. With a full output schema and 100% parameter coverage already present, no critical gaps remain for correct invocation.

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 the schema already documents both parameters. The description adds only a redundant 'limit max 25' and no extra syntax or meaning for q, making a baseline 3 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 (Searches) and resource (French companies) and names the official data source (recherche-entreprises.api.gouv.fr). This clearly distinguishes it from generic company_registry or country-specific siblings like company_br and uk_company.

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 gives no explicit when-to-use or when-not-to-use guidance relative to alternatives. It implies French company lookups but never names or contrasts with sibling tools such as company_registry or company_ticker.

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