serial_write

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 only states 'raw data' and special use cases, but does not disclose side effects, prerequisites like an open connection, return values, or the default newline behavior. For a mutating tool, this is insufficient.

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?

Two concise, front-loaded sentences immediately state the action and use cases. Zero filler, perfect length for the tool's simplicity.

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 write tool with no output schema, the description is brief but lacks important context about prerequisites (e.g., establishing a serial connection), possible return values, or edge cases like newline handling. It is minimally adequate but not complete.

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 schema covers 100% of parameters (data and newline) with descriptions, so the baseline is 3. The description adds context about 'raw data' and special sequences but does not provide additional parameter-level semantics beyond the schema.

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 writes raw data directly to the serial port, using a specific verb and resource. It also distinguishes itself from sibling tools like serial_log (reading) and file_write by emphasizing 'raw data' and special sequences.

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?

Provides explicit use cases ('sending special key sequences, break signals, or interacting with bootloaders'), giving clear context for when to use the tool. However, it does not mention alternative tools or exclusion criteria, so it slightly misses the 'when-not' aspect.

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