Add Hatch Boundary

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

Annotations only provide destructiveHint=false, so the description carries most of the behavioral disclosure burden. It adds valuable detail: every edge is validated before anything is written, and a malformed list fails as a whole rather than leaving a half-built path. This discloses atomicity and error behavior beyond what annotations provide.

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 and front-loaded: the first sentence gives the exact action, and the second paragraph explains the design rationale and validation guarantee. Every sentence earns its place with no 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?

With a rich input schema, an output schema present, and the validation/atomicity behavior disclosed, an agent has enough to call this tool correctly. The main gaps are explicit routing among boundary-related siblings and whether the added boundary replaces or supplements existing hatch boundaries, but these are not fatal.

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 the edges parameter already documented with concrete shape examples and handle described as 'Handle of an existing HATCH.' The description adds only the notion of typed edges and validation, not new parameter-level semantics, so baseline 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 states a specific verb ('Add'), a resource ('hatch boundary'), and the core mechanism ('built from typed edges'), so the purpose is clear. It does not explicitly name sibling tools such as boundary_from_entities or hatch_edit, leaving differentiation mostly to inference.

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 rationale paragraph implies when this tool is useful: when curves must not be silently straightened, and the handle parameter implies an existing HATCH is required. However, it does not explicitly say when to prefer this tool over boundary_from_entities, boundary_trace, or hatch_edit, nor does it state exclusions.

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