eda_pcb_primitive_get_primitive_board_line

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

No annotations are provided, so the description carries the full burden. It does disclose the return type (IPCB_ComplexPolygon or undefined) and the conditions for undefined (ID not matched or primitive not on specified layers). It implicitly indicates a read operation via 'get', but it does not explicitly state read-only behavior or any other side effects. The disclosure is adequate but minimal.

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 concise, combining a function signature and a brief Chinese phrase, front-loading the purpose. It is not overly verbose and contains no redundant sentences. The bilingual mix is slightly unusual but does not harm clarity.

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 get operation with no output schema, the description states the return type and failure conditions. It does not explain what 'board line' means precisely or explicitly state read-only behavior, but these are reasonably inferred from the name and context. The missing details are minor for an agent to invoke it correctly, especially since the schema handles arg construction.

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 the wrapper parameters (args, windowId) with descriptions, achieving 100% coverage for the schema itself. The description adds the function signature showing primitiveId and layers as parameters, but does not explain their semantics beyond types. It mentions layers are optional and the undefined condition, but does not describe how to format the args array beyond the schema's generic 'JSON parameter array in official signature order'. Baseline 3 applies because schema coverage is high.

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 action: retrieving the border line (board line) of a PCB primitive, with a function signature and Chinese explanation '获取图元的边框线'. It is specific about the resource (primitive's board line) and the verb 'get'. However, it does not explicitly contrast with sibling tools like eda_pcb_primitive_get_primitive_by_primitive_id, so it lacks direct sibling differentiation.

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?

There is no guidance on when to use this tool instead of other primitive-getter tools. The description only explains what it does, not when to select it. No exclusions or alternative recommendations are provided.

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