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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavioral detail: results include Approved/Pending/Rejected status and the rejection reason, and open drafts are included alongside submitted templates. Minor gap is that pagination and ordering are unstated.

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 sentences, no filler, with the scope constraint and the returned fields front-loaded. Every clause carries information an agent needs before calling.

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 single-parameter read-only listing tool with no output schema, the description covers what is returned (templates, statuses, rejection reason, open drafts) sufficiently. The remaining gap is the format and origin of did_id, which neither the schema nor the description resolves.

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?

The single parameter did_id has 0% schema description coverage, so the description must carry the semantics. It only implies that the value identifies 'a number this account owns'; it never says whether this is an internal DID id or a phone number, nor where to obtain it (e.g., list_did_numbers).

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 names a specific verb and resource ('Lists WhatsApp templates'), states the scope ('for a number this account owns') and an extra inclusion ('plus open drafts'). It stops short of naming the sibling tools it complements, such as get_whatsapp_template_status, draft_whatsapp_template, and submit_whatsapp_template, so an agent must infer the boundary from names alone.

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?

Usage is implied by 'lists ... plus open drafts' – an agent can infer this is a discovery step before revise_whatsapp_template or submit_whatsapp_template. However, there is no explicit when-to-use statement and no routing away from the closely related get_whatsapp_template_status, which also returns template state.

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