cast_scan

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

Annotations declare readOnlyHint=true, openWorldHint=true, and idempotentHint=true, and the description is fully consistent with these. The description adds the specific target (Chromecast/DLNA devices), which provides useful context beyond the annotations. No contradictions exist.

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, concise sentence in French that front-loads the action and resource. It contains no filler or redundant information, making it highly 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?

For a simple, parameterless discovery tool, the description adequately states the action and scope. It does not explicitly describe the return format, but the tool name and description imply a list of devices. Given the annotations and lack of an output schema, it is sufficiently complete.

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 tool has zero parameters, so the description need not explain parameter semantics. The schema coverage is 100% (trivially, since there are no parameters), and the description adds no unnecessary information.

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 scans for available Chromecast/DLNA devices on the network, using a specific verb (scan) and resource (devices). It differentiates from sibling cast_* tools that perform casting actions, making the purpose unambiguous.

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 implies this is the discovery step before casting, but it does not explicitly state when to use it versus alternatives. The context of sibling tools makes the intended usage clear, and there are no exclusions or alternative references, so it earns a 4 for clear context.

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