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

Annotations already cover safety (readOnlyHint=true, destructiveHint=false, openWorldHint=true), yet the description adds substantial behavioral context beyond them: the 1,000-row cap, the explicit caveat that the list is not exhaustive, the count-vs-report reconciliation in the response, the last-crawl-date field, the note that non-Website sources usually cannot be fixed, and the Cotlet API key auth requirement.

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?

Front-loaded with what the tool returns, then constraints, then pagination and auth. Dense but each sentence carries information; only mild length cost.

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 read-only listing tool with no output schema, the description supplies everything an agent needs: return contents, limits, completeness caveats, pagination mechanics, and the auth prerequisite. Nothing material is missing.

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 meaningful connective semantics: that status takes either 'indexed' or a report reason, and that the response's next_cursor must be passed back as cursor for the next page. That linkage is genuine added value over the schema's standalone field docs.

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 names a specific verb (\"list\") and resource (URLs from the Page indexing report) and states the exact scope: indexed URLs, or URLs grouped by a specific not-indexed reason. An agent can immediately tell this apart from inspect_url or list_page_issues without opening either schema.

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?

Usage context is implied through the data source and the status parameter's meaning, but the description never explicitly routes the agent against siblings such as list_page_issues or inspect_url, nor states when this tool is the wrong choice. Adequate but leaves the selection decision to inference.

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