WebSocket and texthooker API

SubMiner streams the current subtitle over local WebSockets and serves a texthooker page, so browser tools and your own scripts can follow along. This page is the reference for building a client. If you only want subtitles in a browser tab for Yomitan, see Texthooker page.

Surface	Default	Purpose
websocket	ws://127.0.0.1:6677	Plain subtitle text
annotationWebsocket	ws://127.0.0.1:6678	Subtitle text plus token metadata and rendered HTML
texthooker	http://127.0.0.1:5174	Bundled texthooker page, preconfigured for your setup
mpv plugin	script-message subminer-*	Start, stop, toggle, and status automation inside mpv

All servers bind to 127.0.0.1 only. There is no authentication.

Enable the services

All three services are off by default. Turn on the ones you need in config.jsonc:

{
  "websocket": {
    "enabled": "auto",
    "port": 6677,
  },
  "annotationWebsocket": {
    "enabled": true,
    "port": 6678,
  },
  "texthooker": {
    "launchAtStartup": true,
    "openBrowser": false,
  },
}

• websocket.enabled: true always starts the plain stream. "auto" starts it unless the external mpv_websocket plugin is installed at ~/.config/mpv/mpv_websocket.
• annotationWebsocket.enabled: starts the annotated stream. It is independent of websocket.
• texthooker.launchAtStartup: starts the texthooker page with the app.
• texthooker.openBrowser: opens the page in your browser when it starts.

See Configuration for all related options.

Subtitle WebSocket

ws://127.0.0.1:6677. Use it when you only need the current line as text.

The server pushes only; it ignores client messages. On connect it sends the latest subtitle if there is one, then a new message each time the subtitle changes. Reconnecting is up to the client.

{
  "version": 1,
  "text": "無事",
  "sentence": "無事",
  "tokens": []
}

Field	Type	Notes
version	number	Payload version, currently 1
text	string	Raw subtitle text
sentence	string	HTML-escaped text with line breaks as <br>, no annotation markup
tokens	array	Always empty on this stream

Annotation WebSocket

ws://127.0.0.1:6678. The same token data the bundled texthooker uses. Prefer this stream for new clients. It keeps running when the plain stream is auto-disabled by mpv_websocket.

When a line is not yet tokenized, the stream first sends it with an empty tokens array, then sends the annotated version when tokenization finishes. Treat each message as the complete current state and replace the previous one. The plain stream does not repeat the line for this upgrade.

{
  "version": 1,
  "text": "無事",
  "sentence": "<span class=\"word word-known word-jlpt-n2\" data-reading=\"ぶじ\" data-headword=\"無事\" data-frequency-rank=\"745\" data-jlpt-level=\"N2\">無事</span>",
  "tokens": [
    {
      "surface": "無事",
      "reading": "ぶじ",
      "headword": "無事",
      "startPos": 0,
      "endPos": 2,
      "partOfSpeech": "other",
      "isMerged": false,
      "isKnown": true,
      "isNPlusOneTarget": false,
      "isNameMatch": false,
      "jlptLevel": "N2",
      "frequencyRank": 745,
      "className": "word word-known word-jlpt-n2",
      "frequencyRankLabel": "745",
      "jlptLevelLabel": "N2"
    }
  ]
}

Token field	Type	Notes
surface	string	Display text
reading	string	Kana reading when available
headword	string	Dictionary headword when available
startPos / endPos	number	Character offsets in text
partOfSpeech	string	SubMiner part-of-speech label
isMerged	boolean	Token was merged from several parser tokens
isKnown	boolean	Word is known
isNPlusOneTarget	boolean	Token is the line's N+1 target
isNameMatch	boolean	Token matched a character name
frequencyRank	number	Frequency rank; omitted when unavailable or a name match
jlptLevel	string	JLPT level; omitted when unavailable or a name match
className	string	CSS class list for the token
frequencyRankLabel	string or null	Rank label, set only when the rank is within your frequency highlight settings
jlptLevelLabel	string or null	JLPT label for display

HTML markup

sentence is HTML rendered by SubMiner. Each token is a <span> with these classes as they apply:

• word on every token
• one of word-name-match, word-n-plus-one, or word-known
• word-jlpt-n1 through word-jlpt-n5
• word-frequency-single, or word-frequency-band-1 through word-frequency-band-5, on words that are not known, N+1, or names

Spans also carry data-reading, data-headword, data-frequency-rank, and data-jlpt-level when available. For a fully custom UI, ignore sentence and render from tokens.

Texthooker page

The bundled texthooker is a browser tab that updates live with the current subtitle, works with browser Yomitan, and uses SubMiner's colors. Start it with the app (texthooker.launchAtStartup) or from the launcher:

subminer texthooker      # start the texthooker
subminer texthooker -o   # start it and open the browser

SubMiner injects the page's settings into window.localStorage when it serves it: the WebSocket URL (bannou-texthooker-websocketUrl), the known, N+1, name, frequency, and JLPT coloring toggles, and CSS custom properties for the token colors. The page connects to the annotation stream if it is enabled, otherwise to the plain stream. With neither running, it has nothing to connect to.

Build a client

A minimal browser client for the annotation stream:

<!doctype html>
<meta charset="utf-8" />
<title>SubMiner client</title>
<div id="subtitle">Waiting for subtitles...</div>
<script>
  const subtitle = document.getElementById('subtitle');
  const ws = new WebSocket('ws://127.0.0.1:6678');

  ws.addEventListener('message', (event) => {
    const payload = JSON.parse(event.data);
    subtitle.innerHTML = payload.sentence || payload.text;
  });

  ws.addEventListener('close', () => {
    subtitle.textContent = 'Connection closed; reload or reconnect.';
  });
</script>

A Node client:

import WebSocket from 'ws';

const ws = new WebSocket('ws://127.0.0.1:6678');

ws.on('message', (raw) => {
  const payload = JSON.parse(String(raw));
  console.log({
    text: payload.text,
    tokens: payload.tokens.length,
    firstToken: payload.tokens[0]?.surface ?? null,
  });
});

Tips:

• Handle empty tokens arrays. Text can arrive before tokenization finishes.
• Reconnect on disconnect yourself.
• Use text for logging and automation, and sentence or tokens for display.

Forward lines to a webhook

SubMiner does not send webhooks itself. Relay the stream to your own endpoint instead. This example forwards only lines that contain an N+1 target:

import WebSocket from 'ws';

const ws = new WebSocket('ws://127.0.0.1:6678');

ws.on('message', async (raw) => {
  const payload = JSON.parse(String(raw));
  const hasNPlusOne = payload.tokens.some((token) => token.isNPlusOneTarget);
  if (!hasNPlusOne) return;

  await fetch('http://127.0.0.1:5678/subminer/n-plus-one', {
    method: 'POST',
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify({ text: payload.text, tokens: payload.tokens }),
  });
});

The same pattern works for n8n or Zapier workflows, Discord notifiers, or appending lines to a notes file.

mpv script messages

SubMiner also supports JavaScript app plugins for playback events, mining events, actions, and custom UI. Besides the streams above, you can drive it from other mpv scripts and from the launcher CLI.

The mpv plugin accepts these script messages:

Message	Action
subminer-start	Start the overlay
subminer-stop	Stop the overlay
subminer-toggle	Toggle the visible overlay
subminer-menu	Open the plugin menu
subminer-options	Open the SubMiner settings window
subminer-restart	Restart the overlay
subminer-status	Show overlay status on the mpv OSD
subminer-stats-toggle	Show an OSD hint for the overlay stats key

subminer-start accepts overrides for backend (auto, hyprland, sway, x11, macos), socket, texthooker, and log-level:

script-message subminer-start backend=hyprland socket=/custom/path texthooker=no log-level=debug

The plugin also registers subminer-autoplay-ready, subminer-autoplay-hold, subminer-visible-overlay-shown, subminer-visible-overlay-hidden, subminer-managed-subtitles-loading, subminer-overlay-loading-ready, subminer-overlay-loading-dismissed, and subminer-reload-session-bindings. The SubMiner app sends these to keep the plugin in sync, so do not send them from your own scripts.

While the app is connected to mpv, it also handles two AniSkip messages over the mpv IPC socket: subminer-skip-intro skips the intro, and subminer-aniskip-refresh reloads intro data, for example after your script changes title or episode metadata.

Related pages

• Configuration
• Mining workflow
• mpv plugin
• Launcher script
• Anki integration