sch_selftest

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

With no annotations provided, the description must carry the behavioral burden. It does explain the comparison activity and the one-time post-update usage, which is helpful. However, it does not disclose whether the tool modifies any files, requires kicad-cli to be installed, produces output, or how failures are surfaced.

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?

Two short sentences with no filler. The main action is front-loaded and the usage timing is given immediately after. Every word earns its place.

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 one-parameter tool with no output schema and no annotations, this is adequate but not complete. The description explains what and when, but lacks return behavior, side-effect expectations, and any mention of external dependencies like kicad-cli availability.

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?

The schema already fully describes the single 'project' parameter, including acceptable path forms. The description's 'for a project' adds little beyond the schema, so the baseline 3 is appropriate.

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 description states a specific action ('Compare'), the two resources involved ('text geometry model' and 'kicad-cli PDF output'), and the scope ('for a project'). This clearly differentiates it from sibling tools like sch_lint, sch_inspect, and sch_fix, which have distinct purposes.

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 gives an explicit, actionable usage condition: 'Run once after a KiCad update.' This tells the agent when to invoke the tool. It does not explicitly mention alternatives or when not to use it, but the timing guidance is strong and contextually useful.

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