get_countries

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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering the safety profile. The description adds the 'with webcams' constraint, which gives useful context about the data returned, but does not disclose other behaviors like language handling, error conditions, or output structure. This adds minor value beyond annotations, meriting a 3.

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 with zero wasted words. It front-loads the action and resource, making it immediately understandable. This is model conciseness.

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 the tool's simplicity (one optional parameter, read-only, output schema present), the description sufficiently conveys the core purpose. The output schema presumably covers return structure, and the schema covers lang. Missing context about what 'available' means or how lang influences results is minor despite the output schema, so it is adequate 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 description coverage is 100%, with the lang parameter fully documented as a language code (default 'en'). The tool description adds no extra meaning about how lang affects the result or what language codes are valid, so it relies entirely on the schema. Baseline 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 'Get available countries with webcams' clearly states a specific verb (get) and resource (available countries with webcams), and is easily distinguished from siblings like get_regions and get_continents by its focus on countries. However, it does not explicitly name or contrast with any sibling, so it falls short of a 5.

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 no guidance on when to use this tool versus alternatives such as get_regions or get_continents. It simply states the function without any context about use cases, prerequisites, or when to prefer it over other geographic lookup tools.

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