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

No annotations are provided, so the description carries the full burden. It transparently discloses outputs (signed attestation, 0-100 trust score, evidence URLs), behavior (flags newly registered or thin-infrastructure domains), limitations (free tier unsigned and rate-limited), and payment requirements (x402 header, USDC). This is comprehensive and goes beyond what an agent could infer from the schema.

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 dense but every sentence earns its place: purpose, methods, output, bulk/payment alternatives, and transport options are all covered without redundancy. It is front-loaded with a clear question ('Is this company real?') and flows logically from purpose to invocation details.

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?

Given no output schema and only a single parameter, the description provides all essential context for correct invocation: what the tool does, what it returns, how to access paid features, and rate-limit caveats. An agent has enough information to call this tool correctly without additional documentation.

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% and the only parameter 'domain' is fully described in the schema. The description adds no additional parameter-specific meaning beyond the schema, so the baseline 3 applies. It does not need to compensate because the schema is sufficient.

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 verb and resource: 'Verify a company or domain is legitimate and established'. It explicitly details the verification mechanisms (RDAP, DNS, email posture, HTTPS) and output (signed attestation, trust score, evidence URLs), distinguishing it from sibling tools like verify_claim, verify_freshness, and verify_price, which target different purposes.

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 explicit use-case scenarios: 'before your agent pays an invoice, onboards a vendor, or trusts it', and mentions bulk endpoint and payment options for signed attestations. It lacks an explicit 'when not to use' or direct comparison to sibling tools, but the context is clear enough for an agent to select this tool correctly.

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