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

Annotations already declare non-readonly, non-idempotent, non-destructive, so the description's key contribution is disclosing the async contract: it returns a job_id and requires polling get_job. It also reassures that existing copper and design rules are preserved, which is meaningful behavioral context beyond the annotations. It does not say what happens on routing failure or how long the job takes.

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 compact sentences, front-loaded with the action, followed immediately by the follow-up step. Nothing is wasted or buried.

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 correctly compensates by naming the return value (job_id) and the polling target (get_job), which is exactly what an agent needs to complete the workflow. Only failure/error behavior is left unstated.

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 coverage is 100% and there is only one parameter, so the schema already explains design_id. The description adds only that routing applies to the whole board ('every unrouted connection'), which slightly clarifies the parameter's scope but is otherwise baseline.

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 clear scope: 'Routes every unrouted connection on the board with PCBEditor's router.' The scope qualifier ('every unrouted') distinguishes it from a general board-editing tool, though it never names which sibling to use instead (e.g., edit_board or design_board).

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?

Usage is implied by the name and the phrase 'unrouted connection' – an agent can infer it should call this after placing components but before exporting. There is no explicit when-not guidance, no prerequisites (e.g., DRC clean), and no named alternative tool.

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