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

The destructiveHint and title come from annotations, so the description doesn't repeat them. It adds the POST endpoint and the minimum-viable-input rule, but says nothing about side effects, duplicate handling, or permission requirements for a write operation with 14 optional fields.

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 tight sentences with the core constraint front-loaded. Including the raw REST endpoint is marginally useful but slightly noisy for an agent-facing definition.

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 14-parameter write tool with no required fields, no output schema, and thin schema descriptions, the description is under-specified. It gives no sense of which fields map to the client record versus contacts, nor what a successful call returns.

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 only 29% across 14 parameters, so the description must compensate and largely doesn't. 'At least a name or one contact' is the only param-level guidance and only touches two of the fourteen fields; the rest (address, vat_number, country_id, etc.) are undocumented in both places.

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 ('Create a client') and adds that contacts can be created inline, which differentiates it from get_client/update_client/list_clients in the sibling set. It doesn't explicitly name an alternative, but the purpose is unambiguous.

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?

'Give at least a name or one contact' supplies a genuine precondition for calling the tool, which is useful. It stops short of stating when to prefer this over siblings (e.g. update_client for existing clients) or how it interacts with list_clients lookups.

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