blender.update_object

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

With no annotations, the description carries the full burden and delivers: explicit unit conventions (meters, degrees), the OBJECT_ALREADY_EXISTS failure for name collisions instead of silent 'Name.001' renaming, the side effect that a missing material is created, and the 'material_created' response flag. These are non-obvious behaviors an agent could not infer from the schema.

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 partial-update rule, then a scannable field-by-field list where every line contributes new information (units, error behavior, or side effects). No filler sentences.

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 9-parameter mutation tool with no annotations and no schema descriptions, the definition covers semantics, units, error cases, and side effects thoroughly, and an output schema exists to cover return values (which the description still references via 'material_created'). Nothing essential to correct invocation is missing.

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, and it does: it defines units and axis order for location/scale/rotation/dimensions, notes dimensions replaces scale, and explains that material_color is only used when creating a material and sets both viewport colour and shader. Only the obvious 'name' identifier is left implicit.

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 opens with a specific verb+resource ('Change an existing object') and immediately scopes it as a partial update ('Only the fields you pass are touched'). This clearly distinguishes it from sibling create_object/delete_object, which operate on different lifecycles.

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?

It gives strong operational context — omitted fields retain their current value, and material is created on demand — which tells the agent how to call it safely. However, it never names an alternative (e.g. create_object for new objects, or the transaction siblings) or states when not to use this tool.

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