verify_phone_code

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

No annotations are provided, so the description must carry the full burden of behavioral disclosure. It only states the action without revealing potential side effects, whether the code is single-use, what happens on invalid code, authentication needs, or the success/failure response. This is insufficient for a mutating verification operation.

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 directly states the purpose without any redundant wording. It is front-loaded and every word earns its place, making it highly concise and well-structured.

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 tool's simplicity (one parameter, no output schema, no annotations), the description is minimally adequate for an agent to understand the action. However, it does not describe the outcome of verification (e.g., what indicates success or failure), which is a gap since no output schema exists to explain return values.

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 fully describes the 'code' parameter as a '6-digit verification code', so the description adds minimal additional semantic value. The mention of SMS/voice call provides minor context about the code's source, but it doesn't compensate for the lack of deeper parameter guidance since the schema already covers the essential information.

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 ('Verify') and the specific resource ('WhatsApp Business phone number') with the method ('code received via SMS or voice call'). It effectively distinguishes from sibling tools like request_verification_code which issues the code, and register_phone which registers without verification.

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 usage by mentioning the code received via SMS/voice, indicating this is a follow-up to a code request. However, it does not explicitly state prerequisites, when to use this instead of alternatives (e.g., register_phone), or any exclusions, leaving the usage context only implied.

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