list_niagara_data_interface_classes

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

Annotations already declare the safe-read profile (readOnly, idempotent, non-destructive), so the bar is lower. The description adds real behavioral context beyond them: enumeration is process-wide via TObjectIterator and abstract classes are filtered out, which tells the agent what will and won't appear in the result.

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, followed by the filtering constraint, the intended use, and the return shape. Three tight sentences with no filler; every clause carries 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?

No output schema exists, but the description supplies the full return contract (count plus per-class fields including abstract and class_flags), and with no input parameters and a safe-read annotation set, nothing an agent needs in order 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?

The tool takes zero parameters, so the baseline is 4. The description adds no parameter detail because there is none to add, and it appropriately spends its words on the return shape instead.

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 precise verb+resource (enumerate every concrete UNiagaraDataInterface subclass) plus the mechanism (TObjectIterator) and the exclusion (abstract base classes). An agent can immediately distinguish it from list_niagara_renderer_classes or list_niagara_modules, which enumerate different registries.

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 ties usage to a downstream tool: 'Used to discover what data-interface class strings are valid for add_niagara_data_interface.' That gives a clear use-before-X context. It stops short of naming an alternative enumerator or when-not to call it, so it falls just shy of a 5.

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