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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=true, and the description contributes genuinely useful behavior beyond them: the link expires in 30 minutes and Coexistence is supported. It omits whether links are single-use, whether repeated calls create multiple concurrent links, and any rate-limit or auth constraints — reasonable gaps for a low-complexity tool but not a complete behavioral picture.

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, both load-bearing: the first defines the artifact and its constraints, the second tells the agent what to do with the result. The expiry and the key next step are front-loaded with no filler.

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?

There is no output schema, and the description compensates by telling the agent that a connect_url is returned and should be shared — exactly the information an agent needs after the call. For a two-optional-parameter creation tool this is nearly complete; only edge behavior on expired or repeated links is unstated.

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 100%, so both parameters (state and display_name) are already fully documented in the schema, and the description adds nothing about them. It does mention connect_url, but that is an output rather than an input, so the baseline 3 applies.

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?

Names a specific verb (create) and resource (a short-lived Connect link), plus the concrete flow it serves (Meta Embedded Signup, Coexistence supported) and the 30-minute lifetime. None of the sibling tools (send_text, list_numbers, send_template) do anything similar, so it is unambiguously distinguishable.

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 intended use case is clear — obtain a link for a business to connect its WhatsApp number and hand that link to the owner, which is stated explicitly as a next step. It stops short of naming when NOT to use it (e.g. reusing an existing link, whether an unexpired link can be refreshed) or pointing at any alternative tool for other onboarding paths.

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