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

Annotations already establish read-only, idempotent, and non-destructive behavior. The description adds meaningful context beyond annotations by disclosing what data is available, that results are city-filterable, and that no payment is processed through Kicksmash. No contradiction with annotations exists.

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?

The description is compact and front-loaded: it states the core subject first, lists relevant attributes, then gives filtering guidance and an important policy caveat. Every sentence earns its place with no filler or redundancy.

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 simple one-optional-parameter read-only tool, the description covers the entity type, available fields, filtering capability, and a key payment policy. It does not describe the return envelope or ordering, but given the tool's simplicity and the absence of an output schema, it is sufficiently complete for selection and invocation.

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%, and the schema already documents the single optional city parameter with valid values and omission behavior. The description's 'Filter by city' reinforces the parameter but does not add substantive meaning beyond the schema. 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?

The description clearly identifies the resource as Padel coaches and lists what their pages contain (clubs, lesson length, languages, booking rules). It is distinguishable from the sibling find_clubs because it explicitly targets coaches, not clubs. However, it relies on the tool name for the action verb rather than stating an explicit 'list' or 'get' action.

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 description provides clear usage context: filter by city, and this is for coaches who have listed their page. The payment note ('prices are the coach's to tell; nothing is paid through Kicksmash') helps the agent set expectations. It does not explicitly contrast with siblings like coach_slots or request_coach, so it stops short of a 5.

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