Get PCB equal length groups

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

The read-only, non-destructive, closed-world annotations already establish the safety profile, and "Lists" is consistent with them. The description adds useful reporting context (skew, reference length, tolerance compliance) but says nothing about how toleranceMm affects results or when includeRaw/timeoutMs matter.

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?

A single front-loaded sentence with no filler; the result fields are packed efficiently. It is appropriately sized, though brevity comes at the cost of any operational guidance.

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 read-only query the description adequately sketches the returned data, which matters since there is no output schema. However, with a five-parameter schema containing an undocumented nested target object and no explanation of document targeting, an agent still lacks information needed to invoke it confidently.

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 60%: name, includeRaw, and toleranceMm are documented in the schema, while the nested target object and timeoutMs are undocumented in both places. The description's mention of "tolerance compliance" loosely ties to toleranceMm but adds no syntax or default guidance beyond the schema, so it neither compensates for nor worsens the gap.

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?

"Lists equal length matching groups" names a specific verb and resource, and the enumerated return fields (member net lengths, reference length, max skew, tolerance compliance) make the domain unambiguous. It is distinguishable from nearby siblings such as get_pcb_differential_pairs and get_pcb_net_report, though it never explicitly positions itself against them.

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?

There is no when-to-use or when-not-to-use guidance, no mention of alternatives for related length/matching analysis, and no stated prerequisite (e.g., that a PCB document must be open). The agent must infer the use case from the name alone.

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