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

Annotations cover the safety profile (readOnlyHint=false, openWorldHint=true, non-idempotent, non-destructive), and the description layers on cost (1–4 credits per page), budget-exhaustion behavior (stops and keeps what it read), and the 409/402 refusal conditions. This is far beyond what the annotations alone convey.

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-loads what the tool does, then usage routing, then cost/error semantics, then return behavior. Every clause carries information; no filler.

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?

With no output schema, the description still explains the return shapes (queued run, finished run, or a job for hosted timeouts) and points to list_pages/get_changes for reading results. Nothing needed to call this correctly 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 semantics the schema does not: 'with wait it returns the finished run, except hosted, where a run still going after the time budget comes back as a job for get_job.' That extra hosted-mode nuance materially changes how the wait parameter behaves.

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?

States a specific verb and resource ('Crawl a project's site now with its saved settings, outside its schedule') and immediately distinguishes itself from recrawl_pages and crawl_site by name. An agent can identify the exact operation without opening the 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?

Gives explicit triggers ('after create_project or update_project, or when fresh results are wanted') and names the alternatives with the conditions that select them: recrawl_pages for a few pages, crawl_site for sites with no project. Nothing is left to inference.

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