compile_material

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

Annotations only declare the generic mutation profile (readOnly=false, destructive=true, idempotent=false). The description goes well beyond that: it discloses the concrete side effects (refreshes child material instances and viewports, marks the package dirty without saving), that 'recompiled' is always true, and that shader errors are NOT reported — all behavior an agent would otherwise have to discover empirically.

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?

Dense and front-loaded: side effects first, then the sibling routing, then the return contract. Two long sentences are information-rich but border on overloaded; still, every clause carries distinct information.

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 mutation tool with no output schema, the description supplies the return shape inline, the persistence behavior (no save), the error-reporting limitation, and the sibling alternative. Nothing material an agent needs to call it correctly is missing.

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 100% and already documents the path format and the 'Material not found' failure mode for instances/functions. The description adds nothing about the single parameter, so the baseline 3 applies.

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 (Recompile), the exact resource (a UMaterial asset), names the underlying engine call, and immediately distinguishes itself from the sibling recompile_material_function. An agent can tell what this does and what it does not handle without opening any 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?

Explicitly routes the agent to recompile_material_function for material functions, and the schema adds that instance/function paths fail. It gives a clear positive condition and the main exclusion, though it doesn't enumerate broader when-not cases.

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