Convert an After Effects audio layer to keyframes: creates an Audio Amplitude null with sliders so you can drive audio-reactive animations from sound.
After Effects: Convert Audio to Keyframes on an audio layer (creates "Audio Amplitude" null with sliders) — for audio-reactive animation.
| Name | Required | Description | Default |
|---|---|---|---|
| layer | Yes | Layer name or 1-based index. | |
| compositionName | No | Comp name; omit to use the active comp. |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only declare readOnlyHint=false and destructiveHint=false; the description adds real value by disclosing the side effect — a new null layer named 'Audio Amplitude' with slider properties is created. It does not say whether keyframes are baked per-frame, whether an existing null is reused, or what is returned.
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?
One sentence, front-loaded with the action, with the parenthetical side effect and the use case packed in without waste. Nothing could be trimmed without losing information.
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 2-parameter mutation tool with no output schema, the description covers purpose, side effect, and intended use. The remaining gaps — return value and keyframe density/behavior on the generated null — are modest but would help an agent chain follow-up calls.
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% and both parameters are documented with types and defaults in the schema itself. The description adds only the implicit constraint that `layer` must be an audio layer; it says nothing about compositionName or the string-vs-index form. Baseline 3 applies.
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 concrete verb and resource ('Convert Audio to Keyframes on an audio layer') and names the artifact produced ('Audio Amplitude' null with sliders). This is clearly distinct from generic keyframe tools like ae_setKeyframe or ae_setKeyframes, though it does not explicitly say so.
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 trailing clause 'for audio-reactive animation' gives the intended scenario, which implies when to reach for it. But there is no explicit when-not guidance and no named alternative (e.g., ae_applyExpressionTemplate for linking sliders manually), so the agent must infer routing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.