decimate_mesh

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

With no annotations the description carries the full burden, and it does useful work here: it names the mechanism (edge collapse), and discloses the non-obvious refusal of ratio=1.0 as a no-op. It omits whether the original topology is recoverable/undoable and whether the object must be in a particular mode, which matters for a mutation tool.

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?

Front-loaded with the core action in sentence one, followed by a short rationale, then Args/Returns. The rationale paragraph is slightly padded, and the Returns block partly duplicates the output schema, but nothing is genuinely wasted.

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 two-param mutation tool with an output schema, the description covers purpose, parameters, and one key refusal behavior. The remaining gap is operational prerequisites (target mode, whether modifiers are applied, undo semantics), which an agent would otherwise have to guess.

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 document both params, and it does: object_name is identified as the target mesh, and ratio is defined as the fraction of faces to keep with a worked example (0.5 halves) and a boundary rule (1.0 is refused). This fully compensates for the empty schema descriptions.

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 ('Reduce a mesh's polygon count, collapsing edges to hit a target') and explicitly positions itself against a sibling ('The counterpart to subdivision'), so an agent can tell it apart from subdivide_mesh and remesh without opening a schema.

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?

Gives clear context for when to reach for it: after stacking Subdivision modifiers, when a dense mesh is slowing later operations. It stops short of naming a concrete alternative (e.g. remesh) or stating when-not-to-use, so it is strong but not fully routing.

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