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

Annotations already provide idempotentHint=true, so the description doesn't need to cover idempotency. However, it adds the usage patterns (recurring vs one-off) beyond annotations. It does not describe behavior on conflicts or other side effects, so marginal added value.

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 sentences total: first states purpose, second provides usage guidance. No fluff, front-loaded with key information. Every sentence 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?

Given 7 parameters and output schema, the description covers the core distinction (recurring vs one-off) but lacks details on response, error handling, or prerequisites. Adequate for a create operation but not exhaustive.

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%, so baseline is 3. The description adds meaning by explaining how dayOfWeek, isRecurring, and date are used together (recurring vs one-off), going beyond the schema's property 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 verb 'Add' and resource 'availability window for a resource'. It distinguishes between recurring weekly schedules (day-of-week + recurring=true) and one-off blocks (specific date), making the tool's purpose specific and distinct from siblings.

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 guidance on when to use recurring vs one-off, but does not explicitly state when NOT to use this tool or name alternatives (e.g., set_staff_availability). This is clear context but lacks exclusions.

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