decimate

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

Annotations already flag it as destructive (readOnlyHint false, destructiveHint true). The description adds mode-specific effects beyond annotations: collapse can distort shapes and UVs and should be validated with compare_view, while planar removes flat coplanar faces with minimal shape change. It stops short of describing what data is destroyed or any permission requirements.

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 definition is front-loaded with the core purpose, then uses two compact mode-specific clauses. Every sentence earns its place and parameter names are formatted clearly with backticks.

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 annotations covering the destructive safety profile, the description is nearly complete: it explains behavior and mode selection. The main gap is the required 'object' parameter, which is never mentioned, leaving the agent to infer it from the schema property name.

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?

With 0% schema description coverage, the description must compensate. It explains mode, defines ratio as 0..1 of current triangles, notes target_tris as an alternative, and describes angle in degrees. It entirely omits the required 'object' parameter and does not clarify defaults or the target_tris type.

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 gives a specific verb and resource: 'Reduce the triangle count,' then defines the two operational modes. This clearly separates it from siblings like subdivide (increases geometry) and repair_mesh (fixes topology).

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 provides clear context for each mode: collapse for hitting a ratio/target_tris, planar for cleaning flat subdivided surfaces, and recommends checking with compare_view after collapse. However, it does not state when to choose decimate over alternative reduction tools or list any explicit exclusions.

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