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

Beyond the readOnlyHint annotation, the description adds valuable behavioral context: deterministic execution, no AI, no credit usage, API key requirement, and the output target distinction between Reanimated v4 and the reduced-feature 'animated' core API. These details help an agent set expectations correctly without contradicting the annotation.

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 description is three tight sentences with no filler. It front-loads the core purpose, then covers input modes, output targets, cost model, and access requirements, with every sentence earning its place.

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 tool with five optional parameters and no output schema, the description covers the key operational facts: what it does, how to provide input, what output target is used, and the access constraint. It does not explicitly state that the result is a code string or describe failure modes, but the description together with the rich schema is sufficient for correct usage.

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 input schema already documents all five parameters with 100% coverage, so the baseline is 3. The description adds meaningful context by explaining the two input modes (inline JSON vs scene_id) and clarifying that 'animated' uses a reduced feature set, which enriches the api parameter semantics beyond the schema enum 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?

The description clearly states the tool compiles a scene into a runnable React Native component, which is specific and unambiguous. It does not explicitly name sibling tools or contrast itself with them, so the differentiation is implied rather than stated.

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?

The description gives clear context for when to use the tool: when you want to compile a scene into React Native code, and you can pass inline JSON or a saved scene_id. It also communicates prerequisites and cost characteristics (API key on a paid plan, no AI, no credits), but it does not explicitly list exclusions or alternative tools.

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