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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description adds value beyond those by naming the underlying sources (INSEE Sirene, BODACC) and the kind of intelligence returned (legal notices, proceedings, filings). The explicit 'does not modify any state' line reinforces, rather than contradicts, the annotations.

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?

Three sentences, each earning its place: purpose and format, return content, and data-source/safety context. The key identifying constraint is front-loaded, and there is no filler or redundant elaboration.

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 single-parameter read-only verification tool with no output schema, the description gives enough context: it states the input format, the data sources, and the categories of data returned. It does not enumerate the exact output fields, but that would be better handled by an output schema and is not a critical gap for selecting and invoking this tool.

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 the single 'identifier' parameter as a 9-digit SIREN or 14-digit SIRET. The description repeats that format information, which is helpful in the tool body but adds no meaning beyond what the schema already provides. This matches the baseline for high schema coverage.

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 ('Verify'), names the resource ('French company'), and defines the accepted identifier formats (SIREN 9-digit or SIRET 14-digit). It clearly distinguishes this as a verification tool over official register data, and with no sibling tools there is no ambiguity to resolve.

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?

There are no sibling tools, so alternatives are not applicable, but the description still gives clear context: use this when you need to verify a French company and you have a 9-digit SIREN or 14-digit SIRET. It does not explicitly state when not to use it, but for a single-purpose tool this is a minor omission.

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