pcb_add_fiducial_marks

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

The annotation destructiveHint: true already signals destructiveness, but the description adds no context about what specifically might be altered, whether existing fiducials are replaced, or if any prerequisites exist. For a mutation tool with minimal annotation context, this is a significant gap.

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?

Single sentence, no wasted words. However, it is perhaps too short for the level of complexity, but that is more a completeness issue than conciseness.

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 4 parameters (all with defaults) and a destructive annotation, but the description gives no information on parameter semantics or side effects. An agent cannot accurately invoke this tool without guessing at parameter meanings, making the description insufficient.

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?

With 0% schema description coverage, the description needed to explain 'count', 'margin_mm', 'diameter_mm', and 'allow_open_board', but it does not mention any parameters. The description only says 'near the board corners', which implies margin but not the others.

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 uses the specific verb 'Append' and clearly identifies the resource ('simple fiducial footprints') and location ('near the board corners'). This distinguishes it from sibling tools like pcb_add_mounting_holes and pcb_add_teardrops.

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 gives no explicit guidance on when to use this tool vs alternatives, nor any exclusions. Usage is only implied by the tool name and action, which is insufficient for an agent choosing between similar PCB modification tools.

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