BlenderMCP

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

With no annotations provided, the description carries full burden. It discloses the core behavior (capturing viewport screenshot) and return type (Image), but lacks details about permissions needed, whether it pauses rendering, rate limits, or what happens if viewport is empty. It provides basic behavioral context but misses operational details.

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 perfectly front-loaded with the core purpose in the first sentence, followed by clean parameter documentation. Every sentence earns its place with no redundant information. The structure with clear parameter listing is efficient and scannable.

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 no annotations, no output schema, and low schema coverage, the description provides adequate basics but lacks completeness. It explains what the tool does and the parameter meaning, but doesn't cover return format details (image type, dimensions), error conditions, or integration context with Blender's state.

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?

With 0% schema description coverage and only one parameter, the description adds significant value by explaining what max_size means ('Maximum size in pixels for the largest dimension') and providing the default value (800). This compensates well for the schema's lack of descriptions, though it doesn't explain constraints like minimum/maximum values.

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 specific action ('Capture a screenshot') and target resource ('current Blender 3D viewport'), distinguishing it from sibling tools like get_scene_info or get_object_info. It uses precise technical terminology that identifies the exact functionality.

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 implies usage context (when working with Blender viewports) but provides no explicit guidance on when to use this tool versus alternatives like get_scene_info. There's no mention of prerequisites, limitations, or comparison to other screenshot-related tools that might exist.

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