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

Annotations already declare destructive, open-world, and non-idempotent behavior, and the description adds valuable operational safeguards: show exact sender/recipient/text, obtain explicit confirmation, call once, never auto-retry on uncertain outcomes, avoid restricted data, and note that recording settings may persist content. This meaningfully exceeds what annotations alone 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?

The description is compact and front-loaded: the first sentence states purpose, then the following sentences deliver the safety protocol without redundancy. Every sentence adds meaningful guidance for correct invocation.

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 three-parameter tool with 100% schema coverage, output schema, and strong annotations, the description is complete. It covers the action's purpose, safety workflow, restricted-data constraints, and behavioral side effects, giving an agent everything needed to call it correctly.

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%, so the input schema fully documents all three parameters. The description contributes safety-oriented guidance about showing sender, recipient, and text before sending, but does not add new parameter-level semantics beyond what the schema already provides, so the baseline 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 states a specific verb ('send') and resource ('real external WhatsApp text message through a tenant-scoped Wapiworld instance'). It clearly distinguishes this as the only messaging tool among the sibling tools, which are all read/status/list operations.

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 clearly establishes the action's context and safety expectations, and no competing send tool exists among the siblings. It does not explicitly name alternatives or exclusions, but the 'clear context, no exclusions' level fits because the sibling set is all non-send operations.

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