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

No annotations are provided, so the description carries the full burden. It discloses the auth requirement, the need for a proof account, and a recovery path (start_login then call again), plus the prerequisite of stored credentials. However, it doesn't disclose whether verification is mutating, idempotent, or what failure/success responses look like.

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 core purpose and usage condition are front-loaded in the first sentence. The ACCESS note is slightly verbose but contains necessary auth workflow steps. Overall it is efficient with no redundant 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?

For a one-parameter tool with no output schema and no annotations, the description covers the key prerequisites (stored credentials, auth flow, pending domain) but doesn't say what the tool returns or what happens on failure. It is adequate but leaves the outcome unspecified.

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 description coverage is 100% — the only parameter 'id' is documented as 'Domain ID to verify'. The description adds no further parameter-level detail, so the baseline of 3 is appropriate since the schema already fully documents the parameter.

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 action ('Verify a pending domain'), the resource ('domain'), and the distinguishing method ('using previously stored DNS credentials'). This clearly separates it from sibling tools like verify_domain, check_domain_verification, or start_domain_verification.

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 explicitly says 'Use when credentials are already connected,' which is a clear precondition for selecting this tool. It doesn't name alternative tools or state when not to use it, but the context is clear enough for an agent to route correctly.

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