update_net_class_rules

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 discloses the dry_run preview mode, the requirement to pass expected_sha256 when writing, and the critical units convention (millimetres regardless of document units). It does not mention permissions or failure modes, but the core safety workflow is well covered.

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?

Three sentences, each earning its place: purpose, units, and workflow. It is front-loaded with the main action and contains no redundant or vague wording.

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 11 parameters and no annotations, the description covers the essential operation, the units, and a safe mutation workflow. The output schema exists, so return values need not be described. However, it leaves some parameter semantics (e.g., path, txid, layer) to the schema, which has 0% coverage, so it is not fully complete.

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 coverage is 0%, but the description compensates for key parameters: dry_run and expected_sha256 are explicitly explained, and the millimetres note applies to width, clearance, min_width, max_width, and neck_width. Parameters like path, txid, and layer are not explained in the description, but their purposes are somewhat inferable from context.

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 a specific verb ('Update') and identifies the resource ('verified per-layer width and clearance fields of a PCB net class'), clearly distinguishing it from sibling tools like set_trace_width or set_diff_pair_rules. It is precise about the scope and field targets.

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 clear context for when to use the tool (updating net class width/clearance rules) and a concrete workflow: dry_run=true first, then set dry_run=false only after inspecting the preview and passing expected_sha256. However, it does not explicitly name alternatives or state when not to use this tool, so it stops short of a 5.

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