wa_get_phone_number

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

With no annotations, the description must disclose behavioral traits, but it only states 'Get details' without mentioning error behavior, required permissions, or what 'details' include. No context about read-only nature, rate limits, or response format is provided.

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 of nine words, with no filler or repetition. It is appropriately sized for a simple getter and front-loads the primary action and resource.

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?

There is no output schema or annotations, and the description does not convey what 'details' are returned or any other contextual information. For a simple read tool, this is minimal but lacks completeness regarding the expected response or additional requirements.

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 0%, and the description does not add meaning to the 'phone_number_id' parameter. It vaguely refers to 'specific WhatsApp phone number' but does not clarify the ID format, source, or how it relates to the parameter beyond the parameter's name.

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 ('Get') and the resource ('details for a specific WhatsApp phone number'), distinguishing it from sibling wa_list_phone_numbers which lists all numbers. This is specific and unambiguous.

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 when details for a specific phone number are needed, but it does not explicitly mention alternatives or when not to use this tool. No reference to sibling tools like wa_list_phone_numbers, so guidance is only implicit.

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