set_control_lines

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states what lines are set but does not explain side effects, what happens when dtr/rts are null or omitted, whether the port must already be open, or how this interacts with subsequent reads/writes/resets. The word 'manually' adds some context but not enough behavioral transparency.

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 front-loaded sentence with no filler. The core operation appears first, and the use-case context is compactly parenthesized. 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?

For a simple three-parameter tool with full schema descriptions and an output schema, the definition is mostly adequate. However, behavioral gaps around null semantics and side effects, as well as the absence of explicit routing away from reset_device, leave the agent without enough context to confidently choose and invoke this tool in all scenarios.

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 100%, with each parameter already documented in the schema, so the baseline is 3. The tool description adds no extra parameter meaning beyond the manual-line-control context; port examples and high/low semantics are already in the schema. It neither improves nor harms parameter clarity.

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 a specific action ('Set'), the exact resource ('DTR / RTS modem control lines'), and the manual nature of the operation. The parenthetical context ('bootloader entry, custom reset circuits') reinforces the purpose and helps distinguish this low-level tool from higher-level operations like reset_device.

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 useful context for when this tool might be used, such as bootloader entry or custom reset circuits, but it does not explicitly state when to prefer this over alternatives like reset_device, nor does it provide exclusions or when-not-to-use guidance. Usage is implied rather than explicitly directed.

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