Add Zone

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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is known. The description adds no extra behavioral context such as whether this modifies the board, requires a refill, or is undoable. It does not contradict annotations, but it also does not go beyond them. For a mutation tool, more disclosure (e.g., what happens to existing zones or nets) would be helpful.

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 a single, focused sentence that immediately states the verb, object, and key modifiers. It is concise with no redundant information, and the structure front-loads the essential purpose. Ideal for quick agent comprehension.

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?

Although the output schema exists and annotations cover destructive behavior, the description lacks important contextual information such as when this tool should be used, how it relates to the sibling 'add_copper_pour', and any side effects like needing to refill zones. This leaves the agent underinformed for selecting and invoking the tool correctly in a broader workflow.

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 all six parameters described in the input schema. The description itself adds no parameter-level detail beyond what the schema provides. Since the schema carries the full burden, a baseline of 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 clearly states the action (create) and the resource (copper fill zone/pour) with a specific context (on a PCB layer for a specified net). It is not a tautology and conveys what the tool does. However, it does not distinguish from the sibling tool 'add_copper_pour', which appears to have the same purpose, so it lacks explicit sibling differentiation.

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 provides no guidance on when to use this tool versus alternatives like 'add_copper_pour' or when not to use it. There is no mention of prerequisites (e.g., board must be open) or relationships to other zone-related tools (e.g., 'refill_zones'). The usage context is only implied by the name and description.

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