create_material_function_instance

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

Annotations already declare readOnlyHint=false, destructiveHint=false and idempotentHint=false, so the mutation and non-idempotency profile is covered. The description adds genuine value by disclosing the full return shape (asset_path, instance_name, parent_function_path, created, already_existed, saved) despite there being no output schema, and clarifies that the asset is persisted ('and save it').

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 compact sentences: the action is front-loaded and the return block is separated. Every element carries information; it is only slightly terse on context.

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-required-param create tool with full schema coverage and no output schema, the description supplies the return shape and the save semantics, which is the main gap that structured fields leave open. Usage context remains thin, but the core call requirements are covered.

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%, so all three parameters are already documented in-schema; baseline is 3. The description's 'with parent set' phrase loosely maps to parent_function_path but adds no syntax or format detail beyond the schema.

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: 'Create a UMaterialFunctionInstance (asset, with parent set) and save it.' The parent-setting and save steps narrow it further. However, it does not name any of the many sibling create/function tools (e.g. create_material_function, set_material_function_instance_parent) to help the agent discriminate, so it stops short of a 5.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives among the numerous material-function siblings. The agent must infer usage purely from the name and parameters.

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