audit_tented_via_ratio

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

With no annotations, the description carries the full burden and does well: it explains the counting rules (top/bottom counted separately, through-vias two, buried/blind outer-layer surfaces ignored) so the agent knows what is measured. It doesn't explicitly state read-only/no side effects, a minor omission.

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 with the core action, and the environmental rationale is useful. The 'Returns' block duplicates the existing output schema, which is a small waste but doesn't obscure the front-loaded core.

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, and the description restates the return fields anyway; combined with the counting semantics and rationale, it is essentially complete for a zero-parameter audit tool. Only the read-only/side-effect expectation is left implicit.

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?

Zero parameters, so the baseline of 4 applies. Nothing to document beyond the empty 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?

States a specific verb and resource: count tented vs untented via surfaces on the active board and report the tented ratio. The scope and unit of counting are defined well enough to distinguish it from siblings like pcb_get_vias or pcb_normalize_vias.

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?

Provides clear context on when the ratio matters (humid/salt-spray environments, consumer boards requiring all-vias-tented vs prototyping). It doesn't name an alternative tool or explicit exclusion, so it falls just 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.