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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds that data comes from 'real booking occupancy' and warns against using memory, which is useful behavioral context. However, it doesn't disclose response format, pagination, or what happens when no dates are available. With annotations covering the core safety traits, a 3 is appropriate.

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 with zero waste. The core purpose and data source are front-loaded, and the usage triggers and exclusion are packed into the second sentence. Every word 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 read-only lookup tool with full schema coverage and annotations covering safety, the description is nearly complete. It clearly tells the agent when to call it and what it returns conceptually. The only minor gap is the lack of detail about the response shape, but since there is no output schema and the tool is simple, the description is sufficient for correct invocation.

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 schema already documents all three parameters. The description adds the critical instruction to always use this tool rather than memory, but it doesn't add parameter-level detail beyond the schema. Baseline 3 is correct when the schema does the heavy lifting.

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 states a specific verb ('get'), resource ('free dates and places of a specific tour'), and source ('real booking occupancy'). It explicitly distinguishes from memory-based answers and names the exact user queries it serves. This clearly differentiates it from siblings like get_tour_details and get_tours.

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 when-to-use triggers: 'when a tourist asks when there are places, whether a date is free, which dates are possible.' It also gives a strong when-not-to-use rule: 'do not name dates and places from memory, only from here.' This is exemplary routing guidance.

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