Get the QR code to link a number

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

Annotations already indicate readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds valuable behavior beyond annotations: QR codes rotate every 20 seconds, it waits during account startup, and returns status or pairing code depending on link state. This is helpful context that annotations do not provide.

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 sentences that are front-loaded with the purpose and then behavioral notes. It is concise and well-structured, though the second sentence packs multiple facts that could be slightly reorganized for readability.

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 simple read-only tool with annotations covering safety and schema covering parameters, the description explains all key runtime behaviors: waiting, rotation, and conditional return values. Nothing essential for correct invocation is missing.

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 description coverage is 100% for both parameters, so the schema already documents them. The description adds context about waiting behavior and rotation that relates to waitSeconds and the overall operation, enriching the meaning beyond the schema definitions.

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 retrieves a QR code for linking a device in WhatsApp, with specific context (Settings > Linked devices). It distinguishes its purpose from a generic 'get' but does not explicitly differentiate it from sibling tools like request_pairing_code, though it mentions pairing code behavior.

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?

No explicit guidance on when to use this tool versus alternatives. It gives retry advice (call again if expired) but does not mention any sibling tools or conditions that would make another tool more appropriate, such as using request_pairing_code for phone-number linking.

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