List Transactional WhatsApp

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

Annotations already declare readOnly, idempotent, closed-world, non-destructive, so the safety profile is covered. The description adds value beyond that by disclosing that results include delivery status and by giving output-presentation guidance (don't surface ids/timestamps unless requested), which is real behavioral context not in the annotations.

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?

Three front-loaded sentences; the purpose leads and the definition of 'transactional' immediately follows. The final presentation note is slightly tangential but short and useful, keeping the whole thing lean.

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 read-only list tool with no output schema, the description covers the resource, scope, return content (delivery status), and presentation guidance, while pagination lives in the schema. It is nearly complete; only the relationship to single-message fetch tools is unaddressed.

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% – after/before cursors and the limit range are fully documented in the schema itself. The description adds no additional parameter meaning, so baseline 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?

States a specific verb (List) and resource (transactional WhatsApp) plus a return attribute (delivery status). It explicitly defines 'transactional' as one-off API sends, not campaigns, which cleanly distinguishes it from campaign-listing and message-fetching siblings.

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 definition clarifies scope by contrasting transactional messages with campaigns (receipts, OTPs), which routes the agent correctly away from campaign tools. However, it never names an alternative tool (e.g. get-whatsapp-message) or states when to prefer a single-message fetch over a list, so it falls short of explicit alternatives.

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