create_via

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

Annotations declare destructiveHint=true, and the description adds critical context: it creates one undo step (Ctrl+Z), warns that it modifies the board, and explains that defaults are used when parameters are omitted. The dry_run option is also disclosed, going beyond the annotation's bare boolean.

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?

Every sentence contributes: core operation, layer connectivity, defaults, undo behavior, dry-run, and a warning. The structure is front-loaded and compact without unnecessary filler.

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?

Given the output schema exists and the description covers side effects, warnings, defaults, and preview mode, the tool is fully contextualized. No gaps remain for an agent to understand what happens and what to expect.

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% with detailed parameter descriptions. The description adds value by explaining default design-rule behavior when diameter/drill are omitted and by explicitly recommending dry_run=true for preview, which is not fully captured in the schema alone.

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 clearly states the tool 'Places a via' at a specified position, defines it as a vertical connection between copper layers, and mentions net assignment. This specific verb+resource statement distinguishes it from sibling tools like create_track or manage_zone.

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 intended use is implied by 'Places a via...' and reinforced with 'Place vias only where connectivity is needed.' It does not explicitly name alternatives or when-not conditions, but the scenario is clear. The dry-run tip provides a safe preview path.

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