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

Annotations already provide readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the behavioral detail that it scans a range and returns the first available dates, but this is largely inferable from the name and schema (e.g., max_dates, days_ahead). It does not disclose additional behaviors such as how availability is determined or whether pricing is included in the response.

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 extremely concise: two sentences with no wasted words. The first sentence states the action and output, and the second provides usage context. It is front-loaded and 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?

The tool has no output schema, so the description should summarize return values; it does so by stating it returns the first N dates with available slots. The schema covers all parameter semantics, and annotations cover safety. However, the description does not explicitly mention that the output includes pricing (hinted by the currency parameter) or how availability is determined in relation to participants, which are minor gaps but not critical given the schema's detail.

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%, with every parameter having a clear description in the input schema. The main description does not add any parameter-level meaning beyond what the schema already provides. The baseline of 3 is appropriate because the schema does the heavy lifting and the description offers no additional semantic detail.

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's function: 'Scan upcoming days and return the first N dates that have available slots.' This is a specific verb (scan) with a clear resource (upcoming days) and output (dates with available slots). It also distinguishes the tool from siblings (e.g., check_availability) by describing a flexible date search, and includes intended use cases ('no specific date in mind' or 'requested date is fully booked').

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 gives explicit guidance on when to use this tool: 'Use this when a visitor has no specific date in mind or when a requested date is fully booked.' This clearly sets the context for use, but it does not explicitly mention alternatives or exclusions (e.g., 'for checking a specific date, use check_availability instead'), so it lacks a full when-not-to-use clause.

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