After Effects MCP

This lets Claude Code, or any MCP client, drive the Adobe After Effects that's open on your computer. It can:

• inspect projects and comps

• build and animate layers with ExtendScript

• preview frames as images

• import files

• render, with live progress on long renders

There are no dependencies beyond Node.js 18+.

Installing with an AI agent? Tell it: "Install the After Effects MCP from https://github.com/LiamcKerr/after-effects-mcp by following its AGENTS.md." The file has step-by-step instructions, a verification script and a fix for every failure.

How it works

MCP client ──stdio──> server/server.mjs ──HTTP 127.0.0.1:47670 + token──> Claude Bridge (CEP extension inside AE) ──> ExtendScript

• cep/ is a small CEP extension with two parts:

  • An invisible host. After Effects starts it on launch, and it runs a local server that passes scripts to AE's script engine one at a time.

  • A status panel, under Window > Extensions > Claude Bridge. It shows whether the bridge is up and lists recent calls, and its Restart bridge button reloads the host.

• server/ is the MCP server: stdio JSON-RPC with no dependencies. All the tool logic lives here.

Related MCP server: After Effects MCP Custom

Tools

Every change is one undo step named "Claude: …", so Edit > Undo in AE reverses it.

Install

The requirements are After Effects 2022 or newer and Node.js 18 or newer. ffmpeg is optional (for .mp4 from sequence renders). The installer registers the server with Claude Code if the claude CLI is installed.

# Windows (tested: Windows 11, After Effects 2025 and 2026)
git clone https://github.com/LiamcKerr/after-effects-mcp.git "$env:USERPROFILE\after-effects-mcp"
cd "$env:USERPROFILE\after-effects-mcp"
powershell -ExecutionPolicy Bypass -File install.ps1

# macOS (written for macOS but not yet tested there)
git clone https://github.com/LiamcKerr/after-effects-mcp.git ~/after-effects-mcp
cd ~/after-effects-mcp && bash install.sh

Then do three things by hand:

1. Restart After Effects.

2. Tick Preferences > Scripting & Expressions > "Allow Scripts to Write Files and Access Network".

3. Start a new Claude Code session.

Check everything with:

node scripts/doctor.mjs        # PASS/FAIL per piece, with the fix for each failure

Keep the repo folder where it is: After Effects loads the extension through a link to cep/.

Other MCP clients

Register a stdio server with command node and argument <repo>/server/server.mjs. For Claude Desktop's claude_desktop_config.json:

{ "mcpServers": { "after-effects": { "command": "node", "args": ["C:\\Users\\you\\after-effects-mcp\\server\\server.mjs"] } } }

Rendering long comps

ae_render { comp: "Main", output_path: "D:/renders/main.mp4", format: "sequence", wait: false }
  -> { job: "render-…", frames: 1800 }
ae_render_status { job: "render-…" }
  -> { status: "running", framesDone: 612, percent: 34, secondsPerFrame: 1.9, etaSeconds: 2257 }
  -> { status: "done", encodedBytes: 48211003, file: "D:/renders/main.mp4" }

• The frames go to main_frames/ next to the output. When the render is done, ae_render_status encodes them to the .mp4 with ffmpeg.

• PNG sequences carry no audio, so mux your soundtrack separately.

• format: "template" (the default) renders straight to one file with an output module template, but AE reports no progress until it finishes.

Security

• Local only. The bridge listens on 127.0.0.1 and needs a random token from bridge.json: %APPDATA%\ClaudeAEBridge on Windows, ~/Library/Application Support/ClaudeAEBridge on macOS. The token is created on first run and readable by your user only.

• No browsers. Requests with an Origin header, or a Host other than 127.0.0.1/localhost, are refused. That blocks web pages and DNS rebinding.

• Full scripting power. ae_run_script can do anything ExtendScript can do in the open project. That's the point, so only your own MCP client should hold the token.

Gotchas

• Dialogs freeze everything. alert, confirm, prompt, or any AE warning dialog (missing fonts, "overwrite?", "undo group mismatch") blocks AE and the bridge until someone clicks. ae_render avoids the ones it can: it deletes an existing output file first and never renders inside an undo group.

• One job at a time. While AE renders or shows a dialog, other calls wait; only ae_render_status answers. A timeout on the MCP side doesn't stop the script in AE.

• One AE at a time. If two versions of AE are open, only the first gets port 47670.

• Preview permission. ae_preview_frame uses saveFrameToPng. A file permission error means the scripting preference above isn't ticked.

• ES3 only. ExtendScript is ES3: no let/const, arrow functions, template strings or JSON, and reserved words must be quoted as object keys.

Testing without After Effects

node test/fake-ae.mjs                                  # real host.js + bridge.jsx with a stand-in AE on :47670
node test/smoke.mjs                                    # initialize, tools/list, ae_status
node test/smoke.mjs ae_run_script @test/roundtrip.json

The stand-in runs modern JavaScript, so it won't catch ES3-only mistakes. Always finish with a live check in AE.

Uninstall

uninstall.ps1 (Windows) or uninstall.sh (macOS) removes the link, the Claude Code registration and the token folder, and leaves the repo in place.

Licence

MIT. See LICENSE.