eda_pcb_primitive_get_primitives_bbox

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

With no annotations provided, the description carries the behavioral disclosure burden. It does usefully state that a missing primitive or one without a BBox yields `undefined`. It does not clarify whether the returned bbox is a union of all requested primitives, or what units are used, but the read-only nature of a getter is evident from the signature and return type.

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?

The description is compact: a signature line, a one-line purpose, and a one-line return behavior. There is minor redundancy in restating the return type, but no wasteful content and the key information is front-loaded.

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 simple getter with no output schema, the description covers the essential calling contract: parameter type, return shape, and the important `undefined` edge case. Missing context, such as bbox semantics for multiple primitives and coordinate units, is relatively minor for this operation.

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 only exposes a generic `args` array and `windowId`, but the description embeds the actual parameter type `primitiveIds: Array<string | IPCB_Primitive>` and the exact return object fields, adding real meaning beyond the schema. It still does not explain how the parameters map into the generic `args` array beyond the schema's generic note.

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 opens with the full API signature `pcb_Primitive.getPrimitivesBBox(primitiveIds: Array<string | IPCB_Primitive>)` and a clear Chinese statement '获取图元的 BBox' (get primitives' BBox). It clearly identifies the resource and return shape, and the `pcb_` prefix and signature set it apart from the schematic sibling. It does not explicitly contrast with other getter tools, so it stops short of a 5.

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 the name and description: an agent should call this when it needs the bounding box of PCB primitives. However, there is no explicit when-to-use or when-not-to-use guidance, and no alternative tools are named, leaving the selection entirely to inference.

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