nostr-video-publisher

name	nostr-video-publisher
description	Use when an AI agent needs to create, upload, transcode, sign, or publish Nostr video events for NosTube or compatible Nostr video clients. Covers kind 34235/34236 event structure, imeta tags, Blossom uploads and mirrors, BUD-10 PATCH chunked upload, subtitles, thumbnails, origin tags, nak publishing, and ffmpeg transcode guidance.
metadata	{"short-description":"Publish NosTube-compatible Nostr video events"}

Nostr Video Publisher

Use this skill when creating or editing Nostr video posts for NosTube-compatible clients.

Workflow

1. Prepare media: inspect codec, duration, dimensions, bitrate, file size, thumbnail, subtitles, and external origin references.
2. Transcode if needed: prefer broadly playable MP4/H.264 + AAC; optionally create a 480p fallback or HLS. See Transcode and Upload.
3. Upload blobs to Blossom: upload video variants, thumbnail, and subtitles. Keep returned url, sha256, size, and type.
4. Build a NIP-71 addressable video event:
   • kind 34235 for normal videos
   • kind 34236 for shorts/vertical-first videos
   • one imeta tag per video variant
5. Sign and publish to write relays. Use exact JSON plus nak sign ... | nak req -w ... if no project publisher is available.
6. Optionally publish kind 1063 file metadata events for mirrored blobs.

Required Event Shape

The event must have:

• content: description text
• created_at: current publish timestamp
• tags:
  • ["d", "<stable-identifier>"]
  • ["title", "<video title>"]
  • ["alt", "<description/accessibility text>"]
  • ["published_at", "<unix seconds>"]
  • ["duration", "<seconds>"]
  • at least one imeta tag containing url, m, and ideally x, size, dim, image
  • ["L", "ISO-639-1"], ["l", "<language>", "ISO-639-1"]
  • ["client", "nostube"] when publishing as NosTube-compatible output

Load Event Reference for exact tag schema, examples, and parsing compatibility notes.

NosTube Conventions

• Determine kind from the first publishable variant: portrait/vertical (height > width) becomes 34236; otherwise use 34235.
• Use d as the addressable identifier. Keep it stable for edits/replacements.
• Use multiple imeta tags for variants, not multiple URLs in one imeta unless they are fallbacks for the same variant.
• Put thumbnail URLs in every video imeta as repeated image <url> values. Put thumbnail blurhash in blurhash <value> when available.
• Use fallback <url> for alternate Blossom/mirror URLs. NosTube also parses old mirror <url>, but new events should emit fallback.
• Use text-track tags for subtitles: ["text-track", "<vtt-or-srt-url>", "<iso-639-1>"].
• Add origin tags for imported media: ["r", "<source-url>"] plus ["origin", "<platform>", "<external-id>", "<source-url>"] for known platforms.
• Add people as ["p", "<pubkey>", "<relay-hint-if-known>"].

Publishing With nak

Prefer project helpers when working inside NosTube. For standalone agents, write exact event JSON first because imeta is a multi-value tag and shell tag flags can accidentally split it into invalid separate tags.

nak sign --sec "$NSEC" event.json | nak req -w "$RELAY"

Check the installed nak sign --help/nak event --help syntax before scripting; preserve the JSON tag arrays byte-for-byte.

Quality Checklist

Before publishing:

• Video URL opens with HEAD or GET, returns the expected MIME type, and has stable CORS behavior.
• x is the lower-case SHA-256 of the exact uploaded file.
• size is bytes, not MB.
• dim is WIDTHxHEIGHT.
• duration is seconds, rounded or integer-like.
• Thumbnail is uploaded and referenced through image.
• For large files, Blossom upload either uses regular PUT /upload or BUD-10 PATCH /upload after OPTIONS /upload capability negotiation.
• Publish to the user's write relays and any relevant video relays.

References

• Event Reference: complete event schema, imeta, subtitles, origins, mirror announcements, JSON examples.
• Transcode and Upload: ffmpeg recipes, Blossom PUT/PATCH/mirror flows, Nostr auth notes, and CLI-oriented steps.