start_preview_server

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

With no annotations, the description must carry behavioral disclosure, but it fails to mention that this starts a long-running HTTP server, whether it blocks, how to stop it, or what side effects occur. 'Validated' hints at an internal validation step but does not explain behavior or errors.

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 tight sentence with no filler, naming the core action, resource, and purpose. It could be slightly more structured by front-loading the server-starting behavior, but it is concise and readable.

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 tool that launches a server, the description omits crucial context: whether the server runs asynchronously, how to stop it, what the response contains, and what happens if the directory is invalid or the port is occupied. Without an output schema or annotations, this is under-specified for safe autonomous use.

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 0%, so the description should compensate. It only clarifies 'directory' implicitly as the local directory to serve, but says nothing about the 'port' parameter, its default, range, or effect. The parameter names are somewhat self-explanatory, but the description adds minimal semantic value.

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 action ('Serve'), the resource ('a validated local directory'), and the purpose ('for visual asset preview'). It conveys what the tool does, though it does not explicitly contrast with sibling tools like stop_preview_server or server_capabilities.

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?

No guidance is provided on when to use this tool versus alternatives. It does not mention its counterpart stop_preview_server, nor does it explain prerequisites like directory validation, port availability, or when to prefer other server-related tools.

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