kicad.add_line

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

With no annotations provided, the description carries the full burden. It successfully communicates the state requirement (open project needed), but fails to disclose mutation effects, error conditions (e.g., invalid layer names), or whether the operation is idempotent. The 'Add' verb implies creation, but safety/reversibility details are absent.

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 appropriately concise at one sentence plus a prerequisite tag. The '[Requires open project]' constraint is correctly front-loaded for immediate visibility. No redundant filler text, though 'or shape' adds slight ambiguity without adding value.

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 existence of an output schema, the description appropriately omits return value details. However, with 6 parameters and 0% schema coverage, the description should provide more semantic context for the coordinate system and defaults (e.g., confirming x1/y1 is start point). Adequate but with clear 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?

Schema description coverage is 0%, requiring the description to compensate for undocumented parameters. It mentions 'PCB layer' which maps to the 'layer' parameter, but completely fails to explain that x1/y1/x2/y2 represent endpoint coordinates or that 'width' controls line thickness. Minimal compensation for the schema deficit.

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 ('Add') and target resource ('a line or shape to a PCB layer'), distinguishing it from schematic-focused siblings like 'add_wire' by specifying 'PCB layer'. However, the 'or shape' phrasing is slightly ambiguous given the tool name and coordinate-based parameters clearly indicate a line segment.

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 a prerequisite ('[Requires open project]'), but offers no guidance on when to use this tool versus alternatives like 'add_wire' (schematic) or 'create_board_outline', nor does it mention if this is for graphical elements or electrical connections.

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