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

Beyond the annotations (readOnly, idempotent, non-destructive), it adds substantial behavioral context: it reads from a standing census, returns 'unknown' and schedules unknown URLs, reports price when published and user-agent variance, and warns that it is observational and not a guarantee. This is exactly the kind of disclosure an agent needs to use the result correctly.

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 compact but information-dense, front-loading the cost ('FREE') and the trigger ('before fetching a URL') before explaining outcomes and caveats. Every segment adds value, and the bulk alternative is stated in one clause.

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 one-parameter read-only lookup, the description gives the core outcome categories, unknown-URL behavior, and reliability caveat. It does not spell out the exact response fields, but no output schema exists and the stated statuses are sufficient to shape an agent's expectation.

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?

The schema already documents the only parameter fully, including the http/https requirement and max length, and schema coverage is 100%. The description does not add parameter-level meaning beyond naming 'URL' and 'page,' so the baseline score of 3 is 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?

The description states a specific verb and resource ('before fetching a URL, learn whether your crawler identity will be served, refused, or met by a paid tollgate') and enumerates the possible answers. It also names a distinct sibling for bulk use, so it is easy to tell apart from triage_ai_crawler_access.

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 clearly identifies when to call it ('before fetching a URL') and directs bulk needs to triage_ai_crawler_access. It does not explicitly contrast against verify_ai_crawler, watch_ai_crawler_access, or pull_ai_crawler_watch, but the single-URL vs bulk distinction is enough for the most common routing decision.

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