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

Annotations already indicate a read-only, idempotent, non-destructive tool, and the description adds substantial behavioral detail beyond that: proof-of-key control rather than network origin, the operator key-directory fetch, the IP-range check, and the four possible return statuses. It also explicitly avoids false positives on spoofing, which is valuable operational context.

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 longer than average but every sentence contributes: cost, purpose, both verification methods, required inputs, supported operators, return statuses, and a key caveat. It is well-labelled and front-loads the core purpose before detail.

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 tool with seven optional parameters, no required fields, and no output schema, the description provides enough to invoke it correctly: the two mutually relevant input combinations, the meaning of each verification mode, and the return status vocabulary. It covers both invocation modes and the tool's limitations.

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 schema already documents each parameter. The description adds value by grouping parameters into the two verification flows: signatureInput/signatureAgent/url for cryptographic, and ip/userAgent/claimed for network. This clarifies how the parameters work together beyond individual schema entries.

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 states a precise verb and resource: verify whether a crawler is who it claims to be, via cryptographic or network-range evidence. It distinguishes itself from sibling access-focused tools and clearly names the two verification modes. The phrase 'never calls a claim spoofed when it merely cannot be checked' adds a clear behavioral boundary.

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 input-selection guidance: use cryptographic verification when a Web Bot Auth signature is available, and network verification when only an IP/user-agent is available. It does not explicitly name alternative sibling tools or state when not to use this tool, but the context for invocation is clear.

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