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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description's job is to add non-obvious behavior, and it does: the api_key is returned only once on approval, so losing it matters. It does not describe the pending/denied response shape, which is the remaining gap.

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?

Two short sentences, front-loaded with the purpose and followed by the actionable consequence. 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 must convey return values, and it covers the approved case including the one-time api_key. It leaves the non-approved outcomes (pending vs denied) unexplained, which is a real but modest gap for a single-parameter status check.

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% and the device_code property already documents its format and origin in pair_device, so the description adds nothing parameter-specific. Baseline 3 applies when the schema does all the work.

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: check whether the owner approved the device. That is clearly distinct from the sibling pair_device, which initiates the flow rather than reporting on it, though the description never names that sibling directly.

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?

Implies the correct sequence (pair, then poll this for approval) and, more usefully, tells the agent what to do with the result: keep the api_key and pass it to the other tools. It stops short of saying to call repeatedly until approval or what to do on denial.

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