tool_visa_free_destinations

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

No annotations are provided, so the description carries the full burden. It discloses key behaviors: read-only, no auth required, data source is a static snapshot, returns list with fields, invalid codes return empty list, territories may be excluded. This is comprehensive for the tool's simplicity.

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 well-structured with sections (purpose, behavioral notes, usage guidance, args). It is concise—every sentence adds value. Front-loaded with the core function, then additional context.

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 list tool with two simple parameters and no output schema, the description covers all necessary aspects: purpose, when to use, parameters, behavior, and limitations (verify with embassy). It is complete for the tool's complexity.

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 0% (no descriptions in schema), but the description thoroughly explains both parameters: passport_country ('ISO 2-letter passport country code' with examples) and include_categories (comma-separated filter with valid values and default). This adds significant meaning beyond the schema titles.

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 purpose: 'List all countries a passport can enter without a traditional pre-arranged visa.' It uses a specific verb ('list') and resource ('countries a passport can enter'), and distinguishes from sibling tools like tool_check_visa_requirement and tool_check_transit_visa.

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 explicitly states when to use this tool ('broad destination discovery') and when to use alternatives: 'Use tool_check_visa_requirement for a precise single-pair lookup. Use tool_check_transit_visa for transit/layover visa checks, not entry.' This provides clear guidance.

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