Capture the live Blender 3D viewport as an image so agents can visually inspect and judge a 3D scene instead of guessing. Requires the Blender UI to be open.
Screenshot of the Blender 3D viewport (needs the Blender UI open). Returns an image.
| Name | Required | Description | Default |
|---|---|---|---|
| max_size | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, and it does disclose two useful traits: the UI-open prerequisite and that the result is an image. It omits whether the call mutates state (implicitly read-only), image format, and what happens on failure.
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 short sentences, front-loaded with the purpose before the precondition. Nothing is padded, though the extreme brevity is part of why parameter and behavioral detail are missing.
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?
There is no output schema and no annotations, so the description should do more; it covers the output type and prerequisite but leaves the one parameter unexplained. Adequate for a trivial capture tool, but with clear gaps.
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 single parameter max_size has 0% schema description coverage, and the description never mentions it at all. An agent cannot learn from either source whether it is a pixel bound, a byte cap, or what the default 1024 applies to.
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 specific verb and resource ('Screenshot of the Blender 3D viewport'), which is distinct from the render-oriented siblings in concept. However, it never explicitly contrasts itself with blender_render or blender_render_scene, so an agent must infer that this captures the viewport rather than a rendered scene.
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 parenthetical '(needs the Blender UI open)' is a genuine precondition that tells the agent when this call will succeed. There is no guidance on when to prefer this over blender_render/blender_render_scene, nor any statement of what happens if the UI is closed.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.