Attach custom key-value user text metadata to selected objects in Rhino, enabling you to label and organize them with custom attributes.
Attach custom key/value user text metadata to selected objects.
Args:
key: Attribute key name.
value: Attribute value string.
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes | ||
| value | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations are absent, so the description carries the full disclosure burden. It reveals the tool mutates selected objects by attaching metadata, but says nothing about overwriting existing keys, behavior with multiple selected objects, or what happens when nothing is selected.
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 compact and front-loaded with the core action in the first sentence. The Args block is mostly redundant with the schema, but the overall length is appropriate and nothing extraneous is included.
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 simple two-string-parameter tool with an output schema, the definition is minimally adequate. Key gaps remain: overwrite semantics for duplicate keys and confirmation that objects must be pre-selected (only implied by 'to selected objects').
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. Its Args section ('key: Attribute key name', 'value: Attribute value string') is nearly a restatement of the parameter names and adds little beyond the schema, omitting format or constraint details.
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 and resource: 'Attach custom key/value user text metadata to selected objects.' It clearly communicates this is a metadata write operation and distinguishes it from the getter siblings (rhino_get_user_text, rhino_cmd_get_user_text), but it does not differentiate from the near-identical sibling rhino_set_user_text.
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?
No guidance is given on when to use this tool, when not to, or which alternative to prefer. The mention of 'selected objects' implies a prerequisite, but it is never made explicit and the overlap with rhino_set_user_text is left unresolved.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.