pcb_route_differential_pairs

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

With no annotations, the description carries the full burden. It discloses the routing style (parallel L-shaped, negative net offset by gap) and that it reports length deviation. However, it does not state whether existing traces are removed/replaced, which objects are mutated, or how the deviation report is delivered.

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 a single compact sentence, front-loaded with the core action and containing the method and report behavior. Every phrase earns its place with no filler or redundancy.

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 mutating 4-parameter tool with no annotations and no output schema, the description covers the core routing behavior but leaves gaps: no return-value format, no side effects, no mention that pairName defaults to all pairs, and no preconditions. It is adequate but 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 100% with defaults for all four parameters, so the baseline is 3. The description adds context for gap as an offset between nets, but this largely restates the schema's '正负线间距' and adds no new parameter-specific syntax or format details.

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 identifies the tool's specific verb+resource: differential pair auto-routing, with the routing method (parallel L-shaped traces, negative net offset by gap) and a distinct output (reports length deviation). This differentiates it from siblings like pcb_route_track, pcb_auto_route_nets, and pcb_create_equal_length.

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?

No guidance is provided on when to use this tool versus alternatives. It does not mention prerequisites such as existing differential pairs, nor does it contrast with pcb_auto_route_nets, pcb_create_diff_pair, or pcb_create_equal_length. The only signal is the tool name and implied use case.

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