list_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 of behavioral disclosure. It mentions the tool lists destinations but doesn't describe key behaviors: whether it's a read-only operation, if it requires specific permissions, how results are formatted (e.g., pagination, sorting), or any rate limits. The return statement is vague ('String containing the list of destinations'), lacking detail on structure.

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 and concise, with three clear sections: a purpose statement, args, and returns. Each sentence serves a specific function without redundancy. It could be slightly more front-loaded by integrating the parameter explanation into the main description, but overall it's efficient.

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 low complexity (one optional parameter) and the presence of an output schema, the description is minimally adequate. However, it lacks completeness for a tool with no annotations: it doesn't explain behavioral aspects like safety, permissions, or result formatting. The output schema existence reduces the need to detail returns, but more context on usage and behavior would improve completeness.

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 description adds meaningful context for the single parameter: it explains that 'destination_type' is an 'Optional destination connector type to filter by.' This clarifies the parameter's purpose beyond the schema, which only shows it as an optional string/enum with a default of null. Since there's only one parameter and the description covers it well, this earns a high score despite 0% schema description coverage.

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 available destinations from the Unstructured API.' It specifies the verb ('List') and resource ('available destinations'), making the function unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'list_sources' or 'list_workflows', which would require 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. It doesn't mention related tools like 'get_destination_info' for detailed information or 'create_destination_connector' for setup. There's no context about prerequisites, such as whether authentication is needed or when listing destinations is appropriate.

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