Modify mesh faces on a Blender object by selecting, deselecting, deleting, filling, grid-filling, triangulating, or poking them, optionally specifying face indices.
Edit mesh faces.
Args: object_name: Target mesh object. action: select, deselect, delete, fill, grid_fill, triangulate, poke. faces: List of face indices (None = selected).
| Name | Required | Description | Default |
|---|---|---|---|
| faces | No | ||
| action | No | select | |
| object_name | Yes |
Changes observed during successful MCP inspections.
v3.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the burden of behavioral disclosure. It does reveal that actions include destructive ones like delete and that faces defaults to selected, but it does not state prerequisites, effects on edit mode, reversibility, or what happens to unlisted faces. For a mutating mesh tool this is a meaningful gap.
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 short and front-loaded, with each line adding necessary information. The Args block is scannable and efficiently conveys parameter semantics. Minor formatting polish could improve it, but it earns its space.
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?
The description covers the key parameters and actions, and for a tool with no output schema that may be sufficient to invoke it. However, it lacks context about edit-mode requirements, the behavior of operations like fill/grid_fill, and the side effects of destructive actions, leaving some ambiguity for an agent.
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 0%, but the description compensates by explaining all three parameters: object_name as target mesh, action with its valid values, and faces as a list of indices with None meaning selected. This goes well beyond the bare schema, though object_name's explanation remains minimal.
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 'Edit mesh faces' gives a clear verb and resource, and the action list (select, deselect, delete, fill, grid_fill, triangulate, poke) sharpens the scope considerably. It does not explicitly differentiate from sibling tools like extrude_faces or subdivide_mesh, but the listed actions make the intended domain clear enough.
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?
No when-to-use or when-not-to-use guidance is provided, and no alternatives are named. The description implies usage by enumerating face actions, but an agent is not helped to choose this tool over edit_mesh_vertices, edit_mesh_edges, extrude_faces, or subdivide_mesh.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.