pair_start

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

With no annotations provided, the description must fully disclose behavioral traits. It only mentions that a PIN appears on screen, but does not address potential side effects (e.g., whether a previous pairing is overwritten), timeouts, or prerequisites. The tool's behavior beyond the PIN appearance is unclear.

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 sentence that front-loads the action and outcome. It is concise and every word contributes to understanding. No unnecessary information is present.

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?

The tool has no parameters and no output schema, so the description is nearly sufficient. It explains what happens (PIN appears), but could be improved by mentioning the need to complete pairing with 'pair_finish' and the PIN. Nonetheless, for a simple initiation tool, it is fairly complete.

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 input schema has no parameters and schema description coverage is 100%. Therefore the description does not need to add any parameter semantics. The baseline of 4 is appropriate since the description adds no extra information but none is required.

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 clearly states the action 'Start pairing with your Vizio TV' and indicates the outcome 'a PIN will appear on screen'. It uses a specific verb and resource, making the purpose unambiguous. It also distinguishes itself from sibling tool 'pair_finish' by implying this is the initiation step.

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 implies when to use the tool (to start pairing), but does not explicitly state when not to use it or mention alternatives. With sibling 'pair_finish', there is no guidance on the sequence of operations. However, for a simple start action, the implied usage is acceptable.

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