Set a keyframe for a specific layer property at a given time.
AI agents use setLayerKeyframe to create or update resources in After Effects MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your After Effects MCP Server environment.
setLayerKeyframe creates or modifies animation data (keyframes) in After Effects compositions. This is a Write operation because it changes the project state reversibly—keyframes can be deleted or adjusted afterward. It does not execute arbitrary code, delete data irreversibly, or trigger destructive effects.
From the tool's definition Tool description states 'Set a keyframe for a specific layer property at a given time' — this modifies layer state by adding/updating a keyframe, which is a reversible change to composition data.
Documented attack patterns abuse exactly the kind of access setLayerKeyframe gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and After Effects MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for setLayerKeyframe:
{
"version": "1",
"default": "deny",
"tools": {
"setLayerKeyframe": {
"limits": [
{
"counter": "setlayerkeyframe_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}setLayerKeyframe stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Set a keyframe for a specific layer property at a given time. It is categorised as a Write tool in the After Effects MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the After Effects MCP Server MCP server in PolicyLayer and add a rule for setLayerKeyframe: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches After Effects MCP Server. Nothing to install.
setLayerKeyframe is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the setLayerKeyframe rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for setLayerKeyframe. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
setLayerKeyframe is provided by the After Effects MCP Server MCP server (thellamainator/after-effects-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from After Effects MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
30 After Effects MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.