render

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

No annotations exist, so the description must fully disclose behavior. It mentions writing to disk and headless runs for blend_file, but lacks details on file overwriting, state changes to the live session, error handling, or blocking behavior. It is adequate but not comprehensive.

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?

One-sentence intro followed by a clean bullet-style list of parameters. Efficient for 9 parameters, though the intro could be slightly tighter. No wasted words.

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?

Covers parameter semantics thoroughly but omits behavioral context: no return value description, no mention of prerequisites (e.g., open scene), and no error handling guidance. With no output schema, the description should provide more operational context for safe invocation.

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 has 0% description coverage, so every parameter meaning must come from the description. The description adds rich value: explains relative vs absolute paths, engine semantics, frame default, transparent meaning, and target options. This is highly effective compensation.

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?

Description clearly states 'Render a still image and write it to disk', a specific verb+resource. It immediately distinguishes from the sibling 'render_and_view' with the recommendation 'Prefer render_and_view so you see it.' No ambiguity.

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 directs to prefer an alternative sibling (render_and_view) and provides practical guidance on engine choice ('EEVEE for iteration; CYCLES for finals') and sample counts ('Keep it low for previews'). This helps the agent decide when and how to use the tool.

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