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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful domain context (the 24h window policy, and that results carry a status), but does not describe response shape or pagination for what is potentially a large listing.

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?

Two tight sentences, no filler, with the core purpose front-loaded and the domain rationale following. Every clause earns its place.

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 read-only single-parameter tool, the definition covers purpose and the key domain constraint. It partially signals return content ('with their status') despite the absence of an output schema, though it leaves the accountId contract and listing behavior unexplained.

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 0% and the single accountId parameter has no description. The phrase 'for an account' implies accountId scopes the result, but the description never states the expected format or how to obtain a valid account id, so it only partially compensates for the schema gap.

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 a well-scoped resource: WhatsApp message templates 'approved by WhatsApp for an account, with their status'. This is clearly distinguishable from the mutating sibling manage_whatsapp_templates without opening either schema.

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 second sentence gives strong situational context: outside the 24h window only an approved template is allowed, so a broadcast needs one of these. That implies when to reach for this tool (pre-broadcast template selection) but stops short of naming alternatives or explicit when-not-to-use conditions.

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