decimate

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

With no annotations provided, the description carries the full behavioral burden and does well: it warns that collapse can distort shapes and UVs and recommends compare_view afterwards. It also explains planar's shape-preserving behavior, though it does not explicitly state whether the operation is permanent or reversible.

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 front-loaded with the core purpose and then efficiently details both modes. It uses two tight sentences with no filler, and the backtick parameter references aid scanning.

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?

Given no output schema and no annotations, the description still gives enough for correct invocation: mode semantics, parameter meanings, and the main risk/check workflow. Minor omissions like the object parameter's expected format and explicit permanence are acceptable but prevent a perfect score.

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%, so the description must compensate. It explains ratio (0..1 of current triangles), target_tris as an alternative, angle in degrees for planar, and the mode enum, but leaves the required object parameter implicit.

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 and resource: reduce the triangle count via decimation. It distinguishes the two modes collapse and planar, making the tool's purpose immediately clear relative to mesh-editing siblings.

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?

It clearly explains when to use each mode: collapse for reaching a ratio/target, planar for cleaning up subdivided flat surfaces. It also advises checking with compare_view after collapse, though it does not explicitly contrast decimate with alternatives like remesh or repair_mesh.

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