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

Annotations only flag destructiveHint=true; the description adds real behavioral context on top: the site must belong to the authenticated user, bearer-token auth is re-validated server-side, and holding presigned URLs is insufficient to finalize. It also discloses the return value (live site URL). Does not cover idempotency or partial-failure behavior, hence a 4 rather than 5.

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?

Four sentences, no padding, and the prerequisite call is front-loaded before the parameter detail. Slightly dense in the completions sentence but every clause carries load-bearing information.

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 terminal mutation step with no output schema, the description covers the prerequisite call, the conditional parameter shape, the auth/ownership constraint, and the success return value. It is nearly complete; only failure and retry semantics are absent.

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 genuine meaning: it explains that versionId comes from the start response and that the completions array exists only for multi-part uploads, with the empty-uploadId exemption for single-part files. This clarifies the cross-call data flow the schema cannot express on its own.

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 ('Commit a deploy') plus the resource and the exact sibling that must precede it ('deploy_create_upload'). An agent can distinguish this from deploy_files or create_site without opening any 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 clear triggering context: it must follow deploy_create_upload and consume that call's versionId. It also states the conditional rule that single-part uploads (empty uploadId) need no completion entry. It stops short of naming an alternative tool or describing failure/recovery paths, so it falls just short of a 5.

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