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

Annotations already declare 'readOnlyHint: true', so the description does not need to repeat that. It adds the API endpoint reference, which is minor behavioral context. No further behavioral traits (e.g., rate limits, response structure) are disclosed.

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 crisp sentences with no wasted words. The first sentence communicates the core purpose, and the second provides a helpful API reference. Every part earns its place.

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 list tool with full schema coverage and no output schema, the description adequately covers the essentials. It could optionally mention that results are read-only (though annotations handle that) or that an empty list implies no availability, but it is sufficiently complete given the tool's complexity.

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 the baseline is 3. The description does not add any information beyond what the schema already provides for parameters like timezone or calendarID. It mentions 'given date' and 'appointment type' but those are already specified in required fields.

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 action ('List'), the resource ('available time slots'), and the constraints ('on a given date for an appointment type'). It effectively distinguishes from sibling 'acuity_availability_dates' by focusing on times within a specific date.

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 implies usage for checking times on a specific date but provides no explicit guidance on when to use this tool versus alternatives like 'acuity_availability_dates' or when to avoid it. No exclusions or prerequisites are mentioned.

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