Route Trace

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

Annotations already declare destructiveHint=true and readOnlyHint=false, covering the mutation aspect. The description adds valuable behavioral context by warning that the tool does NOT handle layer changes and requires a fixed layer, which is important for correct usage. It doesn't fully describe all side effects, but the annotation coverage plus the added caveat make this above average.

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 sentences, front-loaded with the main purpose and a concise warning. No wasted words, and the structure clearly separates the core function from the critical limitation and alternative.

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 presence of an output schema and rich sibling context, the description covers the essential purpose, key limitation, and alternative usage. It doesn't need to detail return values due to the output schema, and it provides enough context for a routing tool with a layer-change caveat.

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% with each parameter (start, end, layer, width, net) having a clear description. The tool description adds context about the 'fixed layer' and 'XY points' but does not significantly elaborate on parameter meanings. Baseline 3 applies as 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?

The description clearly states the tool routes a trace segment between two XY points on a fixed layer, with a specific verb and resource. It also distinguishes itself from the sibling route_pad_to_pad by explicitly noting it does not handle layer changes, making its purpose unambiguous.

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 explicit usage guidance: when start and end are on different copper layers, use route_pad_to_pad instead, which auto-inserts a via. This clearly indicates when not to use this tool and names the alternative, fulfilling the 'when/when-not/alternatives' criterion.

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