Mux

Lightweight, dependency-free, in-memory fake of the Mux Video API for testing code that uses the real @mux/mux-node SDK.

Default port: 4839

Quick start

import { MuxServer } from "./services/mux/src/server.js";

const server = new MuxServer(4839);
await server.start();
// ... run your app/tests ...
await server.stop();

Point the real SDK at it (override baseUrl to http://127.0.0.1:4839) or drive the REST API directly:

const auth = "Basic " + Buffer.from("tokenId:tokenSecret").toString("base64");
await fetch("http://127.0.0.1:4839/video/v1/assets", {
  method: "POST",
  headers: { Authorization: auth, "Content-Type": "application/json" },
  body: JSON.stringify({ input: [{ url: "https://example.com/video.mp4" }], playback_policy: ["public"] }),
});

Access via MCP / preview URL

When run inside a parlel pool, reachable at its mapped preview URL (e.g. http://127.0.0.1:4839). MCP clients drive the Video surface (assets, uploads, playback-ids) using MUX_TOKEN_ID / MUX_TOKEN_SECRET for Basic auth.

Implemented operations

State is in-memory and ephemeral. All routes require Basic auth (token id:secret). Created assets are immediately status: "ready".

Assets

POST /video/v1/assets — create an asset (201 { data: { id, status:"ready", playback_ids, ... } }).
GET /video/v1/assets — list assets.
GET /video/v1/assets/:id — fetch an asset.
DELETE /video/v1/assets/:id — delete an asset (204).
GET /video/v1/assets/:id/playback-ids — list playback ids.
POST /video/v1/assets/:id/playback-ids — add a playback id ({ policy }).

Direct uploads

POST /video/v1/uploads — create a direct-upload URL (201 { data: { id, url, status:"waiting", ... } }).
GET /video/v1/uploads / GET /video/v1/uploads/:id — list / fetch uploads.
PUT /video/v1/uploads/:id/cancel — cancel an upload.

Service & inspection (parlel extensions)

GET / — service metadata. GET /health — { status: "ok" }.
POST /__parlel/reset — reset all in-memory state.
OPTIONS * — CORS preflight (204).

Surface coverage

This emulator faithfully replicates the API surface most application code and agents exercise. Anything below the supported lines is either an intentional design choice for a fast, zero-cost local emulator (✓ By design) or a candidate for a future release (⟳ Roadmap) — never a silent inaccuracy.

Legend: ✅ fully supported · ◐ accepted (stored, not strictly enforced) · ✓ by design · ⟳ on the roadmap.

Feature	Status
Asset create/list/get/delete + `data` envelope	✅ Supported
Playback id list/add	✅ Supported
Direct uploads create/get/cancel	✅ Supported
Basic auth (token id:secret)	◐ Presence checked, not verified
Real ingest / encoding / live streaming	⟳ Roadmap — Not performed (assets are instantly "ready")
Mux Data (`/data/v1/...`)	⟳ Roadmap
Signed playback token verification	⟳ Roadmap
Real persistence	✓ By design — In-memory by design — fast, isolated, resets cleanly between tests

Error shapes

Mux uses { error: { type, messages } }:

Status	When
`401`	missing/invalid Basic auth
`404`	unknown asset/upload

Manifest

See services/mux/manifest.json — name mux, port 4839, protocol http, healthcheck /health, env MUX_TOKEN_ID, MUX_TOKEN_SECRET, MUX_BASE_URL.

Configuration — `test.env`

Copy these into your test.env (used by the bridge sidecar flow). Tokens are Parlel's seeded test credentials — any non-empty value is accepted by the emulator, so you rarely need to change them. Swap in real credentials only when pointing at the live service in prod.env.

MUX_TOKEN_ID=parlel
MUX_TOKEN_SECRET=parlel
MUX_BASE_URL=http://parlel-bridge:4839

Mux