serial_get_signals

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, so description adds context like exact signals and return format. No contradictions; description complements annotations well.

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?

Description is concise (5 sentences), front-loaded with purpose, then details parameters and return format. No unnecessary text.

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 (1 parameter, no nested objects, output schema present), description covers purpose, parameters, return format, and error case. Output schema provides detailed return structure, so no need to repeat.

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 has 0% description coverage (no descriptions for params inside GetSignalsInput? Actually the schema includes descriptions for connection_id and response_format, but context says 0% coverage – likely an error in context. Assuming low coverage, description adds meaning by listing signal names and showing example JSON structure.

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 reads the current state of serial port signals, listing specific input (CTS, DSR, DCD) and output (DTR, RTS) signals. This distinguishes it from sibling tools like serial_set_signals which writes signals.

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 a read-only tool, and annotations confirm readOnlyHint=true. It does not explicitly exclude when to use other tools, but the sibling context (serial_set_signals) provides natural contrast.

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