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

There are no annotations, so the description carries the behavioral disclosure burden. It usefully discloses the authentication requirement and the stateful flow ('sign in with start_login — a session opens this tool — then call this tool again'). However, it does not describe return shape, error behavior, or whether repeated calls are safe.

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 and front-loaded: one clear purpose sentence followed by a concise access note. Every sentence adds useful information, and there is no filler or repetition of the tool name.

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 single-parameter getter, the description covers purpose, parameter context, and access prerequisites. However, no output schema exists, and the description only vaguely says 'including challenge details,' leaving the actual response format and possible status values 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%, and the schema already documents session_id as 'Domain verification session ID.' The description reinforces that the tool concerns a domain verification session, but it does not add meaning beyond the schema.

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: 'Get the current status of a domain verification session, including challenge details.' This clearly identifies what the tool does. However, it does not differentiate this tool from nearby siblings like check_domain_verification, check_user_domain_verification, or get_multi_channel_verification_status.

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 gives explicit usage context: a Proof account is required, authentication must happen first, and signing in with start_login opens a session before this tool is called again. This is clear practical guidance, though it does not explicitly state when to choose this tool over alternatives or when not to use it.

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