check_impedance

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

Annotations already cover safety (readOnly, idempotent, non-destructive). The description adds genuinely new behavioral context: the estimation method (IPC-2141 closed form), its accuracy envelope (~10% vs a field solver), and a secondary side effect of flagging P-N gap versus copper clearance rules. Good added value beyond structured fields.

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?

Front-loads the core action, then adds the flagging behavior and the accuracy caveat in two tight sentences. Dense but every clause carries information; no filler.

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?

With no output schema, the description adequately explains what the tool returns (per-pair impedance estimates, comparison to target, clearance-gap flags) and how reliable they are. The main omission is disambiguation from the sibling 'estimate_impedance' and parameter-level detail.

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 description coverage is 0%, so the description must carry parameter meaning. It hints at the stackup input ('using the real stackup') and the comparison target ('compare with the target'), but never names or explains 'tolerance_pct' and gives no formats or defaults, so the compensation is only partial.

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 with scope: estimates every differential pair's impedance on its routed layer against the target, plus flags clearance-rule violations. Clear and detailed, but it never distinguishes itself from the sibling 'estimate_impedance', which an agent could easily confuse it with.

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?

Gives useful context about when the result is trustworthy ('use a solver or the fab's calculator for sign-off') and implies it runs against routed geometry, but offers no explicit when-to-use versus the near-identical sibling 'estimate_impedance', nor prerequisites like needing a routed design.

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