Check Calendar Availability

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds context by repeating 'read-only, safe for unsupervised use,' and details return type (free/busy information) and possible errors (ValidationError, ValueError). This goes beyond the 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?

The description is concise, well-structured, and front-loaded with the main purpose. Each section (args, returns, raises) is clearly separated, and every sentence adds value.

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 tool has 4 parameters and an output schema, the description covers purpose, parameters, return format, and errors. The presence of an output schema means the description does not need to detail the return structure, making it complete.

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?

Despite 0% schema description coverage, the description lists each parameter with a brief explanation (e.g., 'start: Start time in ISO format'). This adds meaning that the schema alone does not provide, compensating for the lack of schema descriptions.

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 tool checks calendar availability for scheduling and returns free/busy information. It is distinct from siblings like calendar_create_event, but could differentiate from calendar_get_free_busy, which also deals with free/busy data.

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 says 'Useful for finding meeting times,' implying usage context. However, it does not specify when not to use this tool or mention alternatives like calendar_get_free_busy, leaving room for ambiguity.

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