crosspad_devices

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

Annotations include readOnlyHint=true, which aligns with a list operation. The description adds valuable context beyond annotations: it discloses that it only lists 'connected' devices (ephemeral), the tagging mechanism (`kind`), and the underlying hardware/VID/PID distinctions — useful for understanding what the data represents without over-explaining.

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?

A single, information-dense sentence. The [ESP HW] prefix scopes the domain, and the vendor/product IDs and revision mapping are packed efficiently. Zero waste — every clause carries meaning.

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?

The tool has an output schema, describing the `kind` field in the description covers the main return-value nuance (esp-native vs stm-bridge). However, it doesn't explicitly state edge cases (e.g., what happens when no devices are connected, or how to distinguish non-CrossPad serial ports), though for a list-only hardware probe these are minor gaps.

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?

Tool has 0 parameters so there are no parameters to document. Schema coverage is 100% (trivially). With no parameters, the baseline is 4, and the detailed description of what the returned `kind` field means substantially enriches the agent's understanding of the output before invocation.

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?

Specific verb+resource ('List all connected USB serial devices') with clear scope. Distinguishes from siblings by classifying CrossPad devices into 'esp-native' and 'stm-bridge' kinds with detailed hardware identifiers (VID/PID, ESP revision). Clearly differentiates from sibling tools like crosspad_check or crosspad_capabilities.

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 explains what it does and the classification logic, providing context on when this device enumeration is relevant. It doesn't explicitly name alternatives or excluded scenarios, but as a list-only zero-parameter tool, the usage context is self-evident and well-covered given the sibling naming is clearly distinct.

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