calc_track_width

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

With no annotations, the description carries the full behavioral burden; it does disclose the conditional behavior (length triggers resistance/drop/loss) and the physical model nuance that inner layers need ~2.5x width because they cool worse. It never states that this is a side-effect-free calculation that does not touch the board, which is the key thing an agent needs to know amid a set of mutating siblings.

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-loaded summary sentence followed by a compact, line-per-parameter Args block; no filler. The opening is a noun phrase rather than a verb clause, a minor structural weakness, but the content is tight and well organized.

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 return values need no explanation, and every input is documented. For a side-effect-free calculator it is nearly complete; it could still note the assumption set (e.g., ambient, formula basis) but nothing essential to correct invocation is missing.

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 compensate and it does: all five parameters are documented with units (amps, C, mm, oz), defaults, and physical meaning, including the non-obvious semantics of internal_layer. This fully covers the gap left by the bare schema.

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 opening sentence names a specific computation (IPC-2221 minimum track width) tied to a specific input (current), and adds the two conditional outputs (resistance and voltage drop) that only appear when length is supplied. An agent can immediately distinguish this from board-mutation siblings like add_track since it is a pure calculation.

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 explicit 'use this when...' vs alternative routing (the closest sibling, analyze_power_budget, is never mentioned). However, the arg documentation embeds practical selection guidance such as '10 C is conservative' and '1 oz = 35 um is the usual default', which helps with invocation but not with tool choice.

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