list_serial_ports

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

No annotations are provided, so the description carries the burden of disclosing behavior. It clearly states this is a read-only listing operation ('List all available serial ports') and offers helpful naming conventions ('STM32', 'CP210x') without promising any side effects. This is sufficient for a simple enumeration tool.

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 concise and front-loaded. The purpose is stated in the first sentence, followed by practical usage instructions. Every sentence contributes value, and there is no fluff.

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 (zero parameters) and the presence of an output schema, the description is complete. It tells the agent when to call it and what to expect, making it fully self-contained for selection and invocation.

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 there is nothing to explain. The baseline for a no-parameter tool is 4, and the description adds useful context about how to interpret the output, which is effective.

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 opens with 'List all available serial ports', a specific verb+resource combination. It further explains the practical use (finding the FC's COM port or /dev/tty* device), which clearly distinguishes it from sibling tools like find_fc or connect.

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 gives clear when-to-use guidance: plug in the FC, run this, and look for a new entry. It implies this is the first step for locating the FC's port. It doesn't explicitly mention alternatives, but the context is enough for an agent to select it appropriately.

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