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

No annotations are provided, so the description carries the full behavioral burden for a mutation tool. It discloses the early-call policy (one contact suffices), which is genuinely useful, but says nothing about permissions, deduplication of existing leads, reversibility, error behavior, or what the call returns.

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 tight sentences, front-loaded with the purpose and immediately followed by the urgency rule. Every clause carries information; nothing is padding. Slightly compressed wording ('Pasar message con resumen breve') repeats what the schema already says.

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 9-parameter write tool with no annotations and no output schema, the description covers the identity and timing of the operation but omits mutation-side context (permissions, dedup, response shape). Adequate to call correctly, thin on consequences.

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%, so all nine parameters are already documented, including the email/phone mutual exclusion. The description only restates the message parameter and reiterates the one-of contact rule, adding no new semantics. 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 and resource: registers a visitor interested in a Cooper service, i.e. a lead. The intent is unambiguous without opening the schema. It does not explicitly distinguish itself from siblings like createOrder, which is a missed opportunity given a 13-tool surface.

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?

Gives a concrete trigger condition ('only when you have ONE contact data point — email OR phone, whichever comes first, don't wait for both') plus two named scenarios: out-of-coverage note-taking and lightweight pre-account signup. No explicit 'when not to use', but the routing intent is clear.

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