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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is known. The description adds context on what overrides mean (modified or blocked availability), which enriches the agent's understanding of the returned data without contradicting 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 a single sentence that is clear and front-loaded with the action ('Get availability overrides'). It contains no extraneous information and is appropriately concise.

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?

This is a simple read-only tool with one parameter and rich annotations. The description adequately explains what the tool returns, and no output schema is present. The information provided is sufficient for an agent to select and invoke the tool correctly.

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?

The schema covers the only parameter (calendarId) with a description, and the coverage is 100%. The tool description does not add additional parameter semantics, but since the schema already handles it, the baseline score of 3 applies.

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 retrieves availability overrides for a calendar, with a parenthetical clarifying that overrides are specific dates with modified or blocked availability. This distinguishes it from siblings like get_calendar_availability and get_calendar_weekly_availability by focusing on overrides.

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 does not explicitly state when to use this tool versus alternatives, nor does it provide exclusions. The use case is implied through the term 'overrides,' but there is no direct comparison to sibling tools such as get_calendar_availability or get_calendar_weekly_availability.

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