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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is fully covered elsewhere. The description adds the useful scoping fact that results are class definitions rather than sessions, but says nothing about pagination behavior or result volume.

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?

A single compact sentence with a parenthetical field list and no filler. The scope disambiguation is front-loaded immediately after the verb+resource, so nothing important is buried.

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, so enumerating the returned fields in the description is genuinely valuable and compensates well. Combined with the scope clarification and full schema coverage, an agent has enough to call this correctly, though pagination expectations remain 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 description coverage is 100%, so all five parameters (page, class_ids, page_length, location_ids, online_bookings) are already documented in the schema. The description only echoes 'location' and 'online-booking settings' as returned fields, adding no filter syntax or semantics beyond the schema — the baseline 3.

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 ('List the class types offered') and enumerates the attributes returned (id, name, category, duration, price, location, online-booking settings). It also explicitly disambiguates scope — 'the class definitions, not individual sessions' — which is the key distinction an agent needs in this domain.

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?

Usage context is implied by the scope statement (definitions, not sessions), but no alternative tool is named and no when/when-not condition is given. With siblings like nookal_list_services and nookal_get_availability, an explicit contrast would have helped route the agent.

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