serial_write

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

With no annotations, the description carries the full burden. It discloses the lease requirement, which is a key precondition. It does not mention whether the write is blocking, whether a response is expected, error behavior, or any side effects on the board. This is minimal but not misleading.

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 compact and front-loaded with the core action. The lease requirement is stated in the second sentence, followed by an 'Args' section that lists parameters with examples. No wasted words; it is efficiently structured.

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 there is an output schema (not shown), the return format is presumably documented. The description covers the core requirement (board_id, data) and the lease prerequisite. It does not explain error conditions (e.g., invalid board, missing lease) or whether the write is synchronous, but for a simple write tool it is reasonably complete. It could be improved with a note about expected behavior on failure.

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 coverage is 0%, so the description must compensate. It provides clear semantics for both parameters, including an example for board_id ('board_a') and for data ('help\r\n'), clarifying that data is a raw string with possible escape sequences. This goes beyond the bare schema and is adequate for basic usage.

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 states a specific action ('Write a raw command string') on a clear resource ('the board's serial port'). It distinguishes from sibling serial tools like serial_read and serial_exchange by specifying it is a write operation. The purpose is unambiguous.

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?

It provides a prerequisite ('Requires active controller lease') which tells the agent it must acquire a lease first. However, it does not explicitly mention when to prefer this over serial_exchange (which likely does write+read) or serial_read. No explicit alternatives are given, leaving the routing partially to inference.

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