blender_python_exec

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

With no annotations, the description carries the full burden and does well: it discloses the execution environment (bpy, mathutils, args dict), the __result__ return convention, and that stdout/stderr and duration are captured. It does not mention permissions, side effects on the open scene, or timeout behavior, which for an arbitrary-code-execution tool would be worth stating.

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?

Front-loaded with the core action, then the input contract, return shape, transport options, and the async alternative in dense, waste-free sentences. No filler.

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 complex 7-parameter code-execution tool with an output schema (so return format need not be restated), the description covers the essentials an agent needs to invoke it. The three undocumented parameters (blend_file, factory_startup, timeout_seconds) are the remaining gap.

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 coverage is 0% and there are 7 parameters, so the description must compensate and largely does: it explains code, script_path, args, and the transport enum with both mode meanings. blend_file, factory_startup, and timeout_seconds are left undocumented, so it falls short of full coverage.

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 ('Execute a Python script in Blender's context') plus the synchronous execution scope, which cleanly separates it from blender_python_exec_async named in the same description. An agent can identify the tool's job without opening the schema.

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?

Gives explicit mutual-exclusion guidance ('provide either code or script_path, not both'), explains the transport choice with the meaning of both enum values, and routes long-running work to blender_python_exec_async. When-to-use and alternatives are both covered.

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