Mark edges sharper than a specified angle as UV seams to prepare hard-surface models for UV unwrapping.
Mark UV seams on sharp edges -- a decent preparation step before unwrap_selected on hard-surface models.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes | ||
| angle | No | Mark edges sharper than this as seams |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description must disclose behavioral traits itself. It states that seams are marked, but doesn't say whether existing seams are overwritten or preserved, which object is affected, whether the operation is reversible, or what the result looks like. The 'preparation step' hint implies intent but doesn't disclose side effects.
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 action-first sentence that communicates purpose and usage context without filler. The mention of unwrap_selected earns its place by helping the agent understand where this tool fits in a workflow.
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 tool with no annotations and no output schema, the description needs to carry more weight. It leaves the required 'name' parameter ambiguous, doesn't explain what happens to existing seams, and omits any indication of success or failure behavior. The purpose is clear, but an agent still lacks enough information to invoke it confidently on the right object.
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 describes the angle parameter well but leaves the required 'name' parameter undocumented. The description doesn't clarify that 'name' refers to an object name or how it selects the target, and with only 50% schema description coverage, this is a notable gap. 'Sharp edges' loosely maps to angle but adds no new parameter-level meaning.
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 a specific action ('Mark UV seams') and resource ('sharp edges'), and distinguishes it from sibling unwrap tools by framing it as a preparation step before unwrap_selected. An agent can immediately tell this tool is for seam marking, not unwrapping.
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 a clear usage context: use it before unwrap_selected on hard-surface models. It doesn't explicitly name when not to use it or alternative seam-marking approaches, but the 'preparation step' framing is enough to guide correct sequencing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.