get_design_rules

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

With no annotations, the description carries the full burden and does disclose a genuinely useful behavioral trait: it is best-effort and falls back to an explanatory message when the KiCad build does not expose design rules over the API. It does not state permissions or whether the values are authoritative for DRC.

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?

Two short sentences, unit of measure front-loaded in the first line, degradation behavior second. Nothing extraneous.

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?

An output schema exists, so the description need not enumerate return fields; it still contributes the unit (mm) and the fallback behavior. Adequate for a zero-parameter read tool, though a note on how these rules relate to run_drc would complete it.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies.

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?

States a specific verb and resource ('Return the board's minimum design-rule constraints in mm'), which is clearly distinct from sibling checks like run_drc or check_clearance. It does not explicitly name or contrast against those siblings, so it stops short of a 5.

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 'best effort' framing implies this is a lightweight read-only query, but the description never says when to call it versus run_drc, check_clearance, or get_netclass_config. Usage is only implied by context, not stated.

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