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

Beyond annotations, the description explains non-obvious behavior: while state is 'qr', each call returns a new image, so the agent should show the latest one. This aligns with idempotentHint=false and adds meaningful operational detail without contradicting the readOnlyHint=true annotation.

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 two sentences long, front-loaded with the tool's purpose, and then provides the essential state behavior. Every sentence earns its place with no filler or repetition.

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 the single parameter, output schema, and annotations, the description covers the main lifecycle: polling while 'qr', showing the latest image, and recognizing readiness once 'paired'. It doesn't mention possible error/expired states, but the output schema likely captures those, so the description is still highly usable.

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 schema already documents pair_id fully as 'the pair_id returned by wa_pair_account' with 100% coverage. The description refers to the pairing context but does not add meaningfully new parameter-level semantics, so the baseline score of 3 is appropriate.

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 tool checks the status of a pairing started with wa_pair_account. It also distinguishes itself from related tools: wa_pair_account starts the pairing, while wa_list_accounts shows accounts after they become paired.

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 gives clear lifecycle context: use it after wa_pair_account to poll the pairing state, and stop once the state becomes 'paired', at which point wa_list_accounts becomes relevant. It is not an explicit 'when not to use' statement but it provides enough contextual guidance.

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