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

Annotations already signal read-only and idempotent behavior. The description adds value by disclosing the slot structure: the 'time' field for booking and the 'display' field for user presentation, plus the lifecycle instruction to check before booking. No contradiction with annotations.

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 sentences with a clear lead action, precise return-value semantics, and a direct usage directive. Every sentence earns its place and nothing is redundant.

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?

Given the annotations cover safety and the schema covers all parameters, the description completes the picture by explaining the shape and usage of the return value. A agent has everything it needs to decide when to call and how to interpret the result.

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 each parameter is already documented. The description does not add parameter-specific insights beyond what the schema provides; it mainly explains the return fields. 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 states the verb 'check' and the resource 'available time slots' for a provider and service, and ties the output to the booking step ('use this for booboooking_book'). This makes the tool's purpose distinct from siblings like booboooking_book or booboooking_find_next_available.

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 explicitly says 'Use this before booking,' which gives clear placement in the workflow. However, it does not explicitly mention when not to use this tool or name alternatives such as booboooking_find_next_available, so it stops short of full exclusion guidance.

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