Auto Dubbing

Sonilo Dubbing

Dub a video into one or more other languages: the speech is translated and re-voiced, producing a new .mp4 per target language (not just an audio track or subtitles).

Setup: See the setup-api-key skill.

⚠️ Cost — read before calling: this is billed per language, with zero free-trial runs — even a trial account is charged from the very first call, unlike every other Sonilo tool. Requesting four languages costs four times as much as one. Confirm the exact language list with the user before calling; do not guess a long list "to be helpful."

⏱ This call is slow. It polls for at least two hours internally regardless of any shorter TIME_OUT_SECONDS — that's the backend's own ceiling for the dubbing pipeline. A call that sits for an hour or more is normal, not a hang. Do not cancel it: the job keeps running and charging either way, and cancelling just loses the easy path to the result (use get_sfx_task, or get_generation_task on the hosted server, to recover it instead).

Transport: MCP or CLI

Pick one at the start of the session and stay on it. Do not mix the two inside a single job, and do not announce the choice.

1. Sonilo MCP tools visible in this session (dubbing and friends) — use them. This is the preferred path: it needs no shell, and it is the only one that survives a very long generation. If a call fails to authenticate — rather than failing on its inputs — this transport is not usable in this session: go to 2 instead of retrying it.
2. No usable Sonilo MCP tools, but sonilo account exits 0 — use the CLI commands below. Same API, same account, same credential file. Probe with sonilo account, not sonilo whoami: whoami exits 0 even when signed out, so it cannot tell the two states apart.
3. Neither — stop and run the setup-api-key skill. Do not call api.sonilo.com with curl to work around it; both transports handle uploads, polling and retries that a bare request does not.

⏱ On the CLI path this call cannot be one command. The backend polls for up to two hours, while a host's shell tool is capped far below that (ten minutes in Claude Code), so sonilo dubbing run in the foreground will be killed with the job still running and already charged. Submit it and poll separately instead:

# --timeout is the CLI's own wait, not the job's: this returns before a host
# shell can kill the process. The id comes from the "Submitted task ..." line.
sonilo dubbing --video-url https://example.com/clip.mp4 --languages es,fr --timeout 300
sonilo tasks wait <task-id>   # repeat until it finishes

The MCP path has no such limit and is the better transport for dubbing.

Quick Start

MCP tool call (recommended)

dubbing(
    video_path="~/Desktop/product-demo.mp4",
    languages=["es", "fr"]
)

Python (pip install sonilo)

from sonilo import Sonilo

with Sonilo() as client:  # reads SONILO_API_KEY
    result = client.dubbing.generate(
        video="product-demo.mp4",
        languages=["es", "fr"],
        timeout=7200,  # seconds — matches the backend's own ~2h ceiling
    )
    for language, path in result.save_all("./dubbed").items():
        print(language, path)

JavaScript / TypeScript (npm install sonilo)

import { SoniloClient } from "sonilo";
import type { DubbingResult } from "sonilo";

const client = new SoniloClient(); // reads SONILO_API_KEY

const result = await client.dubbing.generate(
  { video: "./product-demo.mp4", languages: ["es", "fr"] },
  { timeout: 7_200_000 }, // milliseconds — matches the backend's own ~2h ceiling
);
for (const [language, url] of Object.entries((result as DubbingResult).outputs ?? {})) {
  console.log(language, url);
}

CLI (npm install -g sonilo-cli or pip install sonilo-cli)

sonilo dubbing --video-url https://example.com/product-demo.mp4 --languages es,fr --output dubbed.mp4
# writes dubbed.es.mp4 and dubbed.fr.mp4

--timeout defaults to 7200 seconds already, matching the backend's ceiling. That is fine in a normal terminal; inside an agent host shell, use the shorter submit-and-poll pattern above so the shell tool does not kill the foreground command.

cURL (raw REST API, no MCP host)

curl -X POST "https://api.sonilo.com/v1/dubbing" \
  -H "Authorization: Bearer $SONILO_API_KEY" \
  -F "video=@product-demo.mp4" \
  -F 'languages=["es","fr"]'
# -> {"task_id": "..."}  poll GET /v1/tasks/{task_id} — can take up to ~2 hours

video_url is also accepted instead of an uploaded file, but must be https — the dubbing pipeline fetches the source itself and rejects plain http.

Tool

Parameters

Workflow Tips

• Always ask which language(s) if the user hasn't said, rather than relying on the ["zh_cn", "es", "fr"] default — that default silently bills for three languages.
• Consider lipsync=false when nobody is speaking on camera. Screen recordings, b-roll and voice-over have no mouth to match, and lip-syncing them re-renders the picture for no benefit — the original frames are returned untouched instead, at their own resolution and frame rate. Do not turn it off on a talking-head video unless the user asks: the mouths will visibly keep speaking the original language.
• This is not the music or SFX skills (text-to-music, video-to-music, text-to-sfx, video-to-sfx). It doesn't touch music/SFX at all — it translates and re-voices existing speech.
• Set expectations on time. Tell the user up front this can take up to ~2 hours and that walking away is fine — the result is recoverable afterward.
• Because there is no free trial here at all, if the account is self-serve and hasn't added a payment method, warn the user before calling rather than letting it fail with trial_exhausted (which doesn't even apply — dubbing bills immediately regardless of trial status). Check get_account_services (see account) if unsure about billing status.

Recovering a Timed-Out Call

If the call's own long poll is interrupted (e.g. the host itself times out or the session is closed), the error message — or the task id printed to stderr at submission time — gives you a task_id. Call get_sfx_task(task_id) — get_generation_task(task_id) on the hosted server — to check status and download finished files once ready; see task-recovery.

Output Files

One .mp4 per requested language, named dubbing-<first 8 chars of the task id>.<language>.mp4 — there's no prompt to name files after, so all dubbing output shares the task-id-based name.

Error Handling

Common errors: 401 invalid key, 402 insufficient balance (dubbing has no trial to exhaust — it bills immediately), 413 file too large, 422 invalid parameters or unsupported language code (rejected before any charge), 429 rate limit. See the account skill.