check_whatsapp_optout

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

With no annotations provided, the description carries the full burden. It indicates a read-only check ('check', 'query'), but does not explicitly state it is non-destructive, nor does it disclose any other behavioral traits like rate limits or required permissions.

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 short (two sentences) and front-loaded with a title-like phrase. However, there is slight redundancy between the first phrase and the second sentence. Generally efficient.

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 1-parameter tool with no output schema, the description covers the purpose and parameter adequately. However, it does not hint at the return type (e.g., boolean or list), leaving a gap in completeness.

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 coverage is 100% (one parameter fully described in schema). The description adds a minor clarification ('con prefijo internacional') but does not provide significant additional meaning beyond the schema.

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's purpose: checking if a phone number is in the WhatsApp opt-out list. It uses a specific verb ('verificar' / 'comprueba') and resource ('opt-out list'), and it distinguishes itself from sibling tools like 'add_whatsapp_optout' and 'remove_whatsapp_optout'.

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 the tool should be used to verify opt-out status, but does not explicitly state when to use it versus alternatives, nor does it provide any context about prerequisites or limitations.

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