pairing_status

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

Annotations already provide readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds value by explaining the three possible states (ready, awaiting_qr, error) and the fields included in each, giving behavioral detail beyond what structured annotations convey. No contradictions.

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 a single paragraph that front-loads the purpose and usage, then details the output structure and states. Every sentence contributes meaningful information with no repetition or fluff.

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?

Given that the tool has no parameters and no output schema, the description fully explains what the tool does, when to use it, and what the return value looks like (including state values and additional fields). It is complete for an agent to select and invoke correctly.

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?

Tool has zero parameters, making schema coverage 100% complete. With no parameters, the description does not need to add parameter details. Baseline for zero parameters is 4.

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 explicitly states it reports WhatsApp device-pairing state as a structured `setup_state` envelope. It uses specific verbs ('report the ... state') and clearly identifies the resource. Among siblings, no other tool covers pairing state, so it is well-distinguished.

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 says it is 'for programmatic supervisors that surface the linking QR to their own clients (e.g. a polling daemon)', which gives clear context for when to use. It also notes the tool is read-only with no side effects. It does not explicitly exclude cases or name alternatives, but the context is sufficient.

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