calculate_pcb_panel_rails

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered and the description does not contradict it. Beyond that, the description usefully discloses the governing standards (IPC-2221B §8.4, IPC-SMEMA-9851) and specifics of what is generated (NPTH Φ3.2mm tooling holes, Φ1.0/3.0mm fiducials, V-Cut or mouse-bite features), adding real context over the annotations.

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 sentence, front-loaded with the core action and then ordered by feature group and standards, with no filler. It is dense and clause-heavy, which makes it slightly tiring to parse, but every element contributes information and nothing is redundant.

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 deterministic computation with 100% schema coverage and no output schema, the description supplies the domain framing and the standards that determine the result, which is what an agent needs to invoke it correctly. It could go slightly further by hinting at the shape of the returned panel geometry, since no output schema exists to carry that burden.

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 100%, so every parameter is already documented in the schema, including defaults and the SMEMA 3.0mm minimum for rail_width_mm. The description adds no parameter-level syntax or format detail beyond echoing the V-Cut/mouse-bite distinction already present in depaneling_method. Baseline 3 is appropriate when the schema does the heavy lifting.

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: 'Calculate SMT automated assembly panel frame with breakaway process rails,' then enumerates exactly which features the calculation covers (clamp clearances, SMEMA tooling holes, fiducials, de-paneling). An agent knows precisely what this tool computes. It does not, however, explicitly differentiate itself from near-siblings like optimize_panel_grid or calculate_fiducial_layout, which also touch panel geometry.

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?

The description never states when to use this tool versus alternatives such as optimize_panel_grid (which also arranges panel grids) or calculate_fiducial_layout (which also handles fiducials). There are no prerequisites, no exclusions, and no routing guidance to a sibling tool.

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