blender_render_still

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

No annotations are provided, so the description carries the full burden. It discloses the two execution modes (bridge vs headless) and that headless requires a blend_file, which is useful behavioral context. However, it does not disclose what happens to the current scene in bridge mode, whether the render is blocking or async, or what the output schema contains. The description adds some value but leaves important behavioral details unstated.

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 with no filler. The core action is front-loaded, and the transport guidance is packed efficiently. It could be slightly more structured (e.g., separating parameter notes from usage modes), but it earns 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?

The tool has 7 parameters, no annotations, and an output schema, but the description covers only the main action and transport modes. It does not explain factory_startup, the meaning of the default output path '//render.png', or what the output schema contains. For a render tool with two distinct execution modes, the description is adequate but not complete.

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 0%, so the description must compensate. It does mention output path, resolution, and render engine, which maps to output_path, resolution_x/resolution_y, and engine. However, it does not explain transport, blend_file, or factory_startup beyond the transport/blend_file usage note. The description adds partial meaning but leaves several parameters (factory_startup, resolution defaults) unexplained.

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 ('Render') and resource ('the current scene as a still image'), and distinguishes itself from the sibling blender_render_animation by specifying 'still image'. It also names the two transport modes, which clarifies the tool's scope beyond a generic render call.

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 explicitly tells the agent when to use each transport mode: use transport='bridge' for the live Blender add-on session, or transport='headless' with blend_file='/path/to/file.blend' to render in a separate background Blender process. This is clear usage guidance that also implies the alternative (blender_render_animation) is for animations, not stills.

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