list_serial_ports

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

No annotations are provided, so the description carries full burden. 'List available serial ports' implies a read-only operation, but doesn't disclose whether this requires specific permissions, whether it returns dynamic/static data, what format the list takes, or if there are rate limits. For a tool with zero annotation coverage, this minimal description leaves significant behavioral gaps.

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, efficient sentence with zero wasted words. It's front-loaded with the core purpose and appropriately sized for a simple listing tool. Every word earns its place.

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 (0 parameters, no output schema), the description is minimally adequate but could be more complete. It doesn't explain what 'available' means (connected? detected?), what information is returned about each port, or how this relates to the broader machine control context. For a tool in a complex CNC/machine control server, more contextual guidance would be helpful.

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 0 parameters with 100% schema description coverage, so the schema already fully documents the absence of parameters. The description doesn't need to add parameter information. A baseline of 4 is appropriate for zero-parameter tools where the schema already provides complete 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 action ('List') and target resource ('available serial ports'), making the purpose immediately understandable. It doesn't explicitly differentiate from sibling tools like 'list_machines' or 'connect_to_port', but the specificity of 'serial ports' provides inherent distinction. This is clear but lacks explicit sibling comparison.

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 prerequisites (like whether a connection must be established first), whether this is for discovery before connection, or how it relates to 'list_machines' or 'connect_to_port'. The agent must infer usage context from the tool name alone.

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