pairing_status

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

Discloses a non-obvious side effect beyond the annotations: the first call on an unlinked device starts a background signal-cli link process, and the first call may return 'awaiting_qr' with no payload yet. This complements the readOnlyHint=false / idempotentHint=false annotations with concrete behavioral detail about the state machine and error condition.

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?

Front-loaded with purpose, then the return envelope, then the side-effect caveat and the sibling routing. Dense but every sentence carries operational value; the state-by-state enumeration is slightly verbose but justified for a polling contract.

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 zero-parameter polling tool, it covers the states ('ready', 'awaiting_qr', 'error'), the payload format, the first-call edge case, and the sibling alternative. Although an output schema exists, the inline state description is consistent and leaves no gap an agent needs to call it 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?

The tool takes no parameters, so the baseline is 4; there is nothing to document and nothing to mislead. The description's envelope details are about returns, not parameters.

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 ('Report the Signal device-linking setup state for first-run pairing') and scopes it to a QR-surfacing client use case. It clearly distinguishes itself from the sibling get_status by framing this as the pairing-flow tool.

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?

Explicitly says to poll this to drive a pairing UI, and names the alternative ('call get_status instead to check read/send availability once linked') with the condition that selects it. When-to-use and when-to-switch are both stated.

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