timeline_rename

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

No annotations exist, so the description carries the load, and it does disclose the key non-obvious side effect: entity refs stay valid but a group's ref mutates to 'timeline:<new name>'. It also pre-empts the missing output schema by spelling out the return shape. It does not mention permissions, duplicate-name behavior, or error cases for an invalid item ref.

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 rename scope comes first, then the behavioral consequence, then the exclusion, then the return shape and example — a well front-loaded order. Mentioning the excluded bodies case early prevents a wrong call before the agent reads further, and nothing is padding.

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?

With only two required params, no annotations and no output schema, the description covers the crucial ground: what can be renamed, ref stability, return shape and the sibling to avoid. Gaps remain around failure modes and whether renaming a group affects member refs, which matter for a mutation tool with no annotations.

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 100%, so both parameters are already documented and baseline would be 3. The description adds value beyond the schema by giving a concrete worked example (item=<extrude ref>, name="Base") and by reinforcing that group items are addressed as 'timeline:<name>', which clarifies how item is actually formed in practice.

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 (Rename) and enumerates the exact resource classes it covers: feature, sketch, construction element, timeline group. It also draws a boundary against the nearest confusable sibling, body_rename, by saying bodies are renamed with the body_* tools, not here.

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?

Explicitly tells the agent when NOT to use it (bodies → body_* tools) and what the item argument should reference. It stops short of stating prerequisites, such as the fact that the ref must first come from timeline_list, and gives no guidance for the other rename-adjacent siblings like assembly_rename_component or timeline_edit_* beyond the body exclusion.

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