Assign a texture to faces

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

With no annotations, the description carries the full burden; it usefully discloses the null-to-clear semantics and the cube-only meaning of 'faces'. It does not say whether an existing texture is overwritten, whether the change is undoable, or what happens on invalid texture names.

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?

Two tight sentences, front-loaded with the core action and followed by the one conditional detail. No filler or restatement of the title.

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 3-parameter mutation tool with no annotations and no output schema, the description covers the texture and faces parameters adequately but leaves 'targets' entirely unexplained, which is a real gap given it is required and untyped.

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 coverage is only 33% and the 'targets' parameter is both undocumented and untyped in the schema, yet the description never explains it. The description does add value for 'texture' (name/uuid, or null to clear) and 'faces' (limits sides on cubes), but that value largely duplicates the schema's own 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?

States a specific verb and resource ('Assign a texture ... to cube or mesh faces') plus the clearing behavior with null. It is clearly distinguishable from UV-oriented siblings like bb_set_face_uv and property-oriented ones like bb_set_texture_properties, though it never names a sibling explicitly.

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?

'For cubes, pass faces to limit which sides are changed' gives concrete usage context for one parameter. There is no statement of when not to use it, no prerequisites, and no mention of alternatives such as bb_set_face_uv for coordinate work.

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