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

Goes well beyond the readOnly and idempotent annotations by disclosing the queried registries (GLEIF and SEC EDGAR), the exact data fields returned, and the honest not_found behavior with source attribution. Cost and latency are also disclosed, and there is no contradiction with 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?

Organized with clear sections and front-loaded with the core purpose, examples, and key constraints. The example block is slightly redundant with the WHEN TO USE text, but overall every section contributes to correct invocation and expectation-setting.

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?

Covers what the tool returns, which sources it queries, failure behavior (not_found), cost, latency, and all accepted parameter combinations. Since there is no output schema, the description's explanation of return values and not_found behavior is sufficient for an agent to invoke it correctly.

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 coverage is 100%, so the baseline is 3, but the description adds practical meaning through example queries (e.g., LEI for precise lookup, country to narrow GLEIF results to a jurisdiction). This enriches the schema's parameter descriptions without being redundant.

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 clearly states a specific action (verify) on a specific resource (company official registry record) and names the actual data sources (GLEIF, SEC EDGAR). It also differentiates from related uses by explicitly stating it is not a fraud-detection or KYC tool, which helps an agent distinguish it from siblings like screen_sanctions.

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?

Provides explicit WHEN TO USE scenarios (before signing a contract, qualifying a vendor, validating a counterparty, due-diligence) and WHEN NOT TO USE exclusions (private companies not registered with GLEIF/SEC, not an exhaustive fraud-detection or full KYC screen). However, it does not name a specific sibling tool as an alternative, so it falls just short of full alternative routing.

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