serial_read

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 the tool reads data, implying a read-only operation, but doesn't cover critical behaviors: whether it's blocking/non-blocking, how it handles errors or timeouts beyond the parameter, what happens if no data is available, or the format of returned data. For a read operation with zero annotation coverage, this leaves significant gaps in understanding its runtime behavior.

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, efficient sentence that directly states the tool's purpose without any fluff or redundancy. It's front-loaded with the core action and resource, making it easy to parse. Every word earns its place, achieving maximum clarity with minimal length.

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 complexity of serial communication and the lack of annotations and output schema, the description is incomplete. It doesn't explain what 'available data' means, how the read operation behaves (e.g., streaming vs. buffered), error handling, or return format. For a tool with 3 parameters and no structured output documentation, more context is needed to fully understand its operation and results.

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 all parameters well-documented in the schema (connection_id, timeout, bytes). The description adds no additional parameter semantics beyond what's in the schema—it doesn't explain parameter interactions, typical values, or edge cases. With high schema coverage, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract.

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 verb ('Read') and resource ('available data from a serial port'), making the purpose immediately understandable. It distinguishes itself from siblings like serial_send (which writes) and serial_expect (which reads with pattern matching), though it doesn't explicitly name these alternatives. The description is specific but lacks explicit sibling differentiation, preventing a perfect score.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., requiring an established connection via serial_connect), exclusions (e.g., not for writing data), or comparisons to similar tools like serial_expect or serial_wait_for. Without any usage context, the agent must infer when this tool is appropriate.

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