render_frame

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

With no annotations, the description carries the full burden. It discloses that a file is written to disk and that a file path is returned, which are key behavioral traits. It does not cover edge cases like overwriting or missing compositions, but covers the core side effect adequately.

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 sentences, front-loaded with the verb and resource. Every word earns its place, and there is no wasted content.

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 simple render tool, the description covers the main purpose and return value. The only gap is that compId/compName are optional but the description does not clarify how the target composition is selected (e.g., current active comp). Given the schema already documents parameters, this is a minor omission.

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 the baseline is 3. The description adds context about the output format (PNG) and return value, but does not enrich parameter meaning beyond the schema. It hints at fileName/outputDir defaults indirectly via the default behavior stated in 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+resource+output: 'Render a single frame of a composition to a PNG file on disk.' It clearly distinguishes from sibling tools by focusing on visual rendering and returning a file path, unlike tools that manipulate project structure.

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 phrase 'so the AI can inspect what the comp actually looks like' provides clear context for when to use this tool. However, it does not explicitly mention alternatives or when not to use it, leaving the guidance slightly implicit.

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