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

Annotations already declare destructiveHint=true, so the safety profile is covered structurally. The description adds little behavioral context beyond the endpoint mapping — it does not say whether duplicate customers are rejected, whether an existing customer is matched/merged, or what identifier comes back. It does not contradict the annotation.

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 terse clauses, each carrying distinct information (what it does, when it is unnecessary, and the endpoint). Front-loaded with the action and free of 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?

No output schema exists, so the description should ideally say something about the created record or its identifier, and it stays silent. It handles the routing question well but leaves a 10-parameter, nested-object create call thinly documented.

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 only 20% across 10 parameters (including nested phoneNumbers and streetAddress objects) and the description supplies no field-level meaning at all. With low coverage, the description was expected to compensate with format or required-field guidance, and it does not.

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 + resource ('Create a customer record') and adds the REST mapping (POST /customers). It also clarifies its boundary against sibling create flows, but does not distinguish it from the related bookeo_get_customer / bookeo_update_customer beyond the obvious verb.

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?

Explicitly tells the agent this step is NOT required before booking because bookeo_create_booking can create the customer inline — a genuine when-not-to-use rule with the alternative named. It does not state the positive case where you specifically do want a standalone customer, so it is not quite a 5.

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