get_add_phone_status

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

Annotations only provide readOnlyHint=true, so the description usefully adds the polling contract ('until terminal state') and the auth prerequisite (PROOF_API_KEY or a session opened by start_login). It doesn't describe the returned status values or the response shape, which remains undisclosed.

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?

Purpose is front-loaded in the first sentence and the polling directive is adjacent. The UX aside about showing the user the link is somewhat tangential but genuinely actionable, and the ACCESS block is slightly verbose.

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 polling tool with no output schema, the description covers auth and polling cadence but never explains what statuses or terminal states an agent should expect, leaving the return contract implied.

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?

With one parameter and 100% schema description coverage, the schema already carries the semantics of session_id. The description's phrase 'by session ID' adds nothing beyond what the schema states, so the baseline of 3 applies.

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+resource+scope: 'Check the status of an in-progress phone addition by session ID.' This clearly distinguishes it from the sibling start_add_phone (initiates) and from get_add_email_status (email variant).

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?

Tells the agent to 'Poll until terminal state,' implying this is called after start_add_phone while the flow is in progress. It also routes auth setup via start_login. It stops short of explicitly naming start_add_phone as the prerequisite or stating what the terminal states are.

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