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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered by structured data. The description adds genuine context beyond that: the data is sourced live from Meta and the payload covers quality rating, messaging limit, and name status, which is valuable since there is no output schema. It omits any note on rate limits or behavior for unregistered/invalid numbers.

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?

A single compact sentence with the returned fields front-loaded and no filler. It works as a fragment rather than a full sentence, but nothing is wasted.

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, single-parameter tool with annotations covering safety, the description supplies the return-value vocabulary needed in the absence of an output schema. Remaining gaps (error behavior for unknown numbers, freshness/latency of 'live' data) are minor.

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% and the sole parameter waba_id is documented in the schema, including a pointer to bridge_list_numbers. The description contributes nothing about waba_id (scoping, format, partner-account requirement), so it sits at the baseline for a fully documented single parameter.

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 the resource precisely (live status of a WhatsApp number from Meta) and enumerates what the status comprises: verified name, quality rating, messaging limit, and name status. That is enough to distinguish it from bridge_list_numbers, though the sibling relationship is only implied rather than stated.

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 the phrase 'Live status of a number', so an agent can infer this is the per-number inspection call versus the listing call. However, it never says when to prefer this over bridge_list_numbers or what preconditions (partner registration, number onboarding) must hold.

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