Set the current animation frame in a named Cascadeur scene and return the actual frame number.
Switch to an existing frame; require expected scene name; returns actual frame.
| Name | Required | Description | Default |
|---|---|---|---|
| frame | Yes | ||
| scene | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds useful context beyond that: it returns the actual frame, and it requires the expected scene name as a validation guard against acting on the wrong scene. It still doesn't explain what state is altered by 'switching' or failure behavior, so it adds value but not rich disclosure.
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?
A single front-loaded sentence with no wasted words; the mutation verb and the two key constraints (scene validity, frame existence) all appear up front. It is efficient, if terse.
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 no output schema the description appropriately mentions the return ('actual frame'), and annotations cover the destructive/read-only profile. However, for a mutating frame-switch tool it omits what changes to the current frame state, error conditions, and any auth/context requirements, leaving gaps.
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 partially: 'expected scene name' clarifies that scene is validated against the active scene, and 'existing frame' implies frame must reference a valid existing frame. It doesn't cover the 0–10000 range or format details from the schema, so it is helpful but incomplete.
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 ('Switch to') and resource ('existing frame'), which distinguishes it from the read-only sibling get_current_frame. It doesn't explicitly name alternatives, but the mutation verb and frame target are unambiguous.
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 the operation targets an already-existing frame but offers no when-to-use context, no prerequisites (beyond scene name), and no guidance versus siblings like set_keyframe or get_current_frame. The only hint is the scene-name requirement, which is more parameter semantics than usage routing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.