Mux Video

Upload, manage, and embed videos through Mux’s API and CLI. Integrates with joelclaw’s webhook infrastructure and Inngest event pipeline.

When to Use

Triggers on: “upload video to mux”, “create mux asset”, “embed mux video”, “check video status”, “mux playback”, “direct upload”, “video encoding”, “mux webhook”, or any task involving video hosting via Mux.

Credentials

Stored in agent-secrets:

• mux_token_id — API token ID
• mux_token_secret — API token secret
• mux_signing_key_id — URL signing key ID
• mux_signing_secret — webhook signing secret (per-endpoint, HMAC)

Lease credentials:

secrets lease mux_token_id
secrets lease mux_token_secret

Or use env vars MUX_TOKEN_ID and MUX_TOKEN_SECRET.

Core Operations

Create Asset from URL

Ingest a video from a public URL:

curl https://api.mux.com/video/v1/assets \
  -X POST \
  -H "Content-Type: application/json" \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET} \
  -d '{
    "input": [{"url": "https://example.com/video.mp4"}],
    "playback_policy": ["public"],
    "video_quality": "plus"
  }'

Video quality tiers: basic (fastest/cheapest), plus (default, good quality), premium (highest).

Direct Upload (browser/client-side)

Two-step process:

Step 1: Create authenticated upload URL (server-side)

curl https://api.mux.com/video/v1/uploads \
  -X POST \
  -H "Content-Type: application/json" \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET} \
  -d '{
    "new_asset_settings": {
      "playback_policies": ["public"],
      "video_quality": "plus"
    },
    "cors_origin": "*"
  }'

Response includes data.url (resumable upload endpoint) and data.id (upload ID).

Step 2: PUT the file to the URL (client-side)

curl -X PUT "${UPLOAD_URL}" \
  -H "Content-Type: video/mp4" \
  --data-binary @video.mp4

The URL is resumable — large files can be uploaded in chunks. Use UpChunk for browser uploads.

List Assets

curl https://api.mux.com/video/v1/assets \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET}

Get Asset Details

curl https://api.mux.com/video/v1/assets/${ASSET_ID} \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET}

Delete Asset

curl -X DELETE https://api.mux.com/video/v1/assets/${ASSET_ID} \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET}

Auto-Generated Captions

curl https://api.mux.com/video/v1/assets \
  -X POST \
  -H "Content-Type: application/json" \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET} \
  -d '{
    "input": [{"url": "https://example.com/video.mp4"}],
    "playback_policy": ["public"],
    "auto_generated_captions": [{"language": "en"}]
  }'

Playback

Embed URL

Once an asset is ready and has a playback ID:

https://stream.mux.com/${PLAYBACK_ID}.m3u8

Thumbnail/Poster

https://image.mux.com/${PLAYBACK_ID}/thumbnail.jpg
https://image.mux.com/${PLAYBACK_ID}/thumbnail.jpg?time=10
https://image.mux.com/${PLAYBACK_ID}/animated.gif?start=5&end=10

Mux Player (Web Component)

<mux-player
  playback-id="${PLAYBACK_ID}"
  metadata-video-title="My Video"
  accent-color="#FF0000"
></mux-player>

Install: npm install @mux/mux-player-react for React, or use the web component directly.

React Component

import MuxPlayer from "@mux/mux-player-react";

<MuxPlayer
  playbackId={playbackId}
  metadata={{ video_title: "My Video" }}
  accentColor="#FF0000"
/>

Webhook Events

Mux webhooks are registered at: https://panda.tail7af24.ts.net/webhooks/mux

The webhook provider (packages/system-bus/src/webhooks/providers/mux.ts) handles HMAC-SHA256 verification and normalizes events into the Inngest pipeline.

Key Events

Event Payload Structure

{
  "type": "video.asset.ready",
  "data": {
    "id": "asset_id",
    "playback_ids": [{"id": "playback_id", "policy": "public"}],
    "status": "ready",
    "duration": 120.5,
    "passthrough": "your_custom_id",
    "tracks": [...]
  }
}

The passthrough field carries your custom identifier through the entire pipeline — use it to correlate uploads with your application records.

Building Inngest Functions for Mux Events

// Example: Notify when video is ready
const onVideoReady = inngest.createFunction(
  { id: "mux-video-ready", name: "Mux Video Ready" },
  { event: "mux/asset.ready" },
  async ({ event, step }) => {
    const { data } = event;
    const playbackId = data.playback_ids?.[0]?.id;
    const duration = data.duration;

    // Your logic here — update DB, notify user, etc.
    await step.run("notify", async () => {
      // ...
    });
  }
);

passthrough Pattern

Always set passthrough when creating assets or uploads. This is your correlation ID that flows through all webhook events:

curl https://api.mux.com/video/v1/assets \
  -X POST \
  -H "Content-Type: application/json" \
  -u ${MUX_TOKEN_ID}:${MUX_TOKEN_SECRET} \
  -d '{
    "input": [{"url": "https://example.com/video.mp4"}],
    "playback_policy": ["public"],
    "passthrough": "my-unique-correlation-id"
  }'

Rules

• Always use passthrough for tracking — it’s your only way to correlate webhooks back to your records.
• Don’t poll for status in production — use webhooks. Mux has rate limits.
• Webhook signing secret is per-endpoint — it’s the secret you get when registering the webhook URL in the Mux dashboard, NOT the API token secret or signing key.
• Video quality tiers affect cost — basic for drafts/previews, plus for production, premium only when needed.
• Direct upload URLs expire — default 1 hour timeout. Create them on-demand, not ahead of time.
• Playback IDs are stable — once an asset is ready, the playback ID doesn’t change. Safe to cache/store.