serial_close

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

Description adds context beyond annotations: it warns about blocking other tools and processes. Annotations already indicate destructiveHint=true, which is consistent. No contradiction.

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?

Extremely concise: two sentences plus a brief Args line. Front-loaded with purpose, every sentence is valuable. No redundant information.

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 connection-close tool, the description covers purpose, when to use, parameter semantics, and consequences. Output schema exists but isn't needed. Complete and self-sufficient.

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?

Although schema description coverage is 0%, the description's 'Args' section explains session_id meaningfully: 'Port name of the session to close. Optional if only one session is open.' This adds practical guidance beyond the schema's default null.

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 'Close a serial connection and release the port.' This is a specific verb-resource combination that distinguishes it from siblings like serial_open (opposite operation) and serial_read (different function).

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?

Explicitly advises when to use: 'Always call this when you are done interacting with a device. Leaving a port open blocks other tools...' This provides clear context. Could mention alternatives like serial_force_release, but not necessary for this tool.

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