language-swap

Original：🇺🇸 English

Translated

Translate and dub a video into another language. One worker call preserves each speaker's voice, translates the speech, and returns a fully A/V-synced video. Lipsync ON by default. Use when the user says "translate this video", "dub this in <language>", "make this Spanish/French/Japanese", "translate the audio", or asks for bilingual subtitles on a dubbed/language-swap output. NOT for: subtitles/captions only (use add_captions or video-captions), transcription only (use transcribe_audio directly), or translating on-screen text overlays.

6installs

Sourcepika-labs/pika-plugins

Added on2026-06-21

NPX Install

npx skill4agent add pika-labs/pika-plugins language-swap

SKILL.md Content

View Translation Comparison →

/pika:language-swap

Translate and dub a video into another language while preserving the original speaker's voice. Pipeline: dub (one worker call) → lipsync (default ON) → burn target-language captions or bilingual captions.

The dubbing worker does the heavy lifting in a single call: it transcribes, translates, preserves each speaker's voice server-side (no separate clone step), and returns a fully A/V-synced video — so there is no manual transcribe/clone/TTS/replace chain to manage and no duration-drift handling to do by hand.

Segmented / multi-language dub (per-range languages)

Use this when the user wants different languages on different parts of one video (e.g. first half Spanish, second half Japanese), or wants to translate only some sections and keep the rest in the original voice. Both are the same thing: a timeline of segments, each tagged with a language; any uncovered range keeps the original audio.

mcp__plugin_pika_pika__dub_video

takes a

segments

plan instead of

target_language

(pass exactly one — they are mutually exclusive):

mcp__plugin_pika_pika__dub_video(source_video_url=<video_url>, segments=[
  {start_s: 0,  end_s: 30, target_language: "es"},
  {start_s: 30, end_s: 60, target_language: "ja"}
])

How to build the plan: the user needs to know where the content is before they can pick ranges, so transcribe first — extract the audio with

mcp__claude_ai_pika__extract_audio_from_video

, then

mcp__claude_ai_pika__transcribe_audio(audio=<audio_url>, timestamps=true)

, show the user the timestamped segments, and let them say which time range goes to which language. Then assemble

segments[]

(seconds, ordered, non-overlapping) and make ONE

dub_video

call. There is no separate "video understanding" tool — the timestamped transcript is the understanding step.

Behavior of the segmented path:

Shared voice across all segments. The source speaker is cloned once and every segment — in every language — is spoken in that same cloned voice, then the clone is recycled, all inside the one
```
dub_video
```
call. You never clone or delete a voice yourself.
Keep-original. Any time range NOT covered by a segment plays the original audio (voice + background) untouched. To translate only parts of a video, list only the parts you want translated.
Length-locked. Output stays exactly the source length (each dubbed range is speed-fit to its window), so boundaries line up with the original timeline.
Provider. Mixed-language-per-range always uses the voice-cloning route automatically; the single-call whole-video dubbing route can't mix languages per range, so don't force a single-call provider for a segmented plan. Every covered language must be supported on the voice-cloning route — if one isn't, surface the error and consult
```
references/language-coverage.md
```
.
Result. Same dubbed-video result;
```
target_language
```
echoes the covered languages comma-joined (e.g.
```
"spa,jpn"
```
), and no single
```
transcript_language
```
is returned (the track is multi-language). Lipsync (Step 2, default ON, ≤5 min) still runs on the whole dubbed video. For captions (Step 3), use the returned multi-language
```
subtitles[]
```
in
```
caption_mode="manual"
```
; auto re-transcription can't pick a single language for a mixed track.

mcp__plugin_pika_pika__dub_video

rejects

segments

(older deployment without segmented support), fall back to dubbing each range single-language and concatenating — but prefer the one-call segmented path when available.

Behavior defaults

Target language: required via
```
--to <language>
```
. Prefer language codes:
```
es
```
,
```
fr
```
,
```
ja
```
,
```
de
```
,
```
pt-BR
```
,
```
zh-Hans
```
. The dubbing worker accepts ISO/BCP-47-like tags and normalizes script/region subtags before calling ElevenLabs (for example
```
zh-Hans
```
→
```
zh
```
;
```
zh-Hant-TW
```
→
```
zh
```
).
Lipsync: ON by default — re-matches the speaker's mouth to the translated audio (fal sync-lipsync; the full-video lip-matcher, distinct from the portrait-image animator). Pass
```
--no-lipsync
```
to skip it when the source has no on-camera face or to avoid the meaningful cost (~$4/min on the sync-2-pro tier). Applies only to videos ≤5 min —
```
edit_lipsync
```
hard-caps at 300 s upstream, so longer sources auto-skip lipsync (see Step 2); the dub itself has no length limit.
BGM / background music: kept by default — the dub lays the translated voice over the original music / SFX bed. Pass
```
--no-bgm
```
for a translate-only output: the worker drops the original music and keeps only the translated speech (
```
drop_background_audio=true
```
).
Captions: target-language captions are burned by default. When the user asks for bilingual / dual subtitles, burn the target-language (translated) row on top and the source-language (original) row below it — after dubbing, the translated speech is what's actually being said, so it's the primary row; the original is the secondary reference.
Bilingual captions: enable when the user passes
```
--bilingual-subtitles
```
or asks for "bilingual subtitles", "dual subtitles", "two-language captions", "original + translated subtitles", "双语字幕", or "原文+译文字幕".
Language coverage: if language support is questioned or a language-related upstream error occurs, consult
```
references/language-coverage.md
```
. Do not proactively surface provider-specific language-list details in normal user replies.

State variables produced and consumed

```
video_url
```
: input — from positional arg
```
source_input_url
```
: original positional URL — preserved for diagnostics if
```
video_url
```
is rehosted
```
target_language
```
: text — from
```
--to <language>
```
```
with_lipsync
```
: boolean — defaults true; false only when
```
--no-lipsync
```

no_bgm

: boolean — true when

--no-bgm

(maps to

drop_background_audio=true

)

```
bilingual_subtitles
```
: boolean — true when the user asks for bilingual / dual subtitles
```
dubbed_video_url
```
: dubbed, A/V-synced video — produced by Step 1
```
dub_subtitles
```
: optional target-language timed subtitles from the dub result — consumed by Step 3
```
source_subtitles
```
: optional source-language timed subtitles from the dub result — consumed by Step 3 for bilingual captions
```
dub_transcript_srt
```
: optional target-language SRT from the dub result — returned for review/debugging
```
source_transcript_srt
```
: optional source-language SRT from the dub result — returned for review/debugging
```
source_transcript_language
```
: optional source-language code from the dub result
```
lipsynced_video_url
```
: dubbed video with mouth re-matched — produced by Step 2 (when lipsync runs)
```
caption_target_video_url
```
: final visual video URL before captions are burned
```
final_video_url
```
: video with target-language captions burned in — produced by Step 3

Step 0 — Parse input

Required:

Positional
```
video_url
```
— MUST be
```
https://...
```
```
--to <language>
```
— target language (free-text or BCP-47 code)

Optional:

```
--no-lipsync
```
— skip the default mouth-matching step.
```
--no-bgm
```
— translate-only output; drop the original music/SFX bed.
```
--bilingual-subtitles
```
— burn source-language + target-language subtitle rows.

Infer

bilingual_subtitles=true

from user wording even if the explicit flag is absent.

--to

is missing, STOP and prompt the user — UNLESS the user wants different languages on different parts, or to translate only some sections: that is the per-range segmented path (see "Segmented / multi-language dub" above), which uses a

segments

plan instead of

--to

For the segmented path, first build the time-range plan: extract the audio with

mcp__claude_ai_pika__extract_audio_from_video

, then transcribe it with timestamps via

mcp__claude_ai_pika__transcribe_audio(audio=<audio_url>, timestamps=true)

, show the user the timestamped segments, and capture which time range maps to which language into

segments[]

Outputs:

video_url

target_language

with_lipsync

(default true),

no_bgm

(default false),

bilingual_subtitles

(default false).

Step 1 — Dub the video (state:

dubbed_video_url

)

Call

mcp__plugin_pika_pika__dub_video

with:

```
source_video_url
```
—
```
<video_url>
```

target_language

—

<target_language>

(ISO/BCP-47-like tag, e.g.

es

pt-BR

zh-Hans

)

```
source_language
```
—
```
"auto"
```
```
drop_background_audio
```
—
```
true
```
only when
```
no_bgm
```
is set; otherwise omit (keeps the original music bed)

In Claude plugin installs the tool is exposed as

mcp__plugin_pika_pika__dub_video

. If your host exposes the same Pika server under a different local namespace, call that fully-qualified local tool with the same arguments. The Claude.ai connector surface may lag this plugin-only tool, so do not assume the connector prefix has it.

mcp__plugin_pika_pika__dub_video

is worker-backed: if the response comes back as

{task_id, status}

, poll

mcp__plugin_pika_pika__task_status

until

completed

, then read the dubbed video from the result (

video_url

for a video source;

audio_url

for an audio source). Also capture optional

subtitles[]

transcript_srt

, and

transcript_language

— these are target-language transcript metadata the dub worker produced, consumed in Step 3.

For bilingual captions, also capture optional

source_subtitles[]

source_transcript_srt

, and

source_transcript_language

. These source-language transcript fields are best-effort. The dubbed media is still valid when transcript fields are absent.

Source not worker-fetchable: if

mcp__plugin_pika_pika__dub_video

fails because the source URL cannot be fetched — especially HTTP

4xx

, hotlink protection, UA-gated hosts (Wikimedia/news CDNs), or "Access Denied" errors — do not keep retrying the same call. Rehost first:

Download the source bytes in the client/host environment using a normal browser/download path or an HTTP client with a real user-agent.
Call
```
mcp__claude_ai_pika__upload_asset
```
with the downloaded filename, MIME type, and exact byte size, then upload the bytes to the returned presigned URL.
Set
```
source_input_url = <original URL>
```
and replace
```
video_url
```
with the returned Pika CDN
```
public_url
```
. Do not construct CDN URLs manually.
Retry Step 1 once against the Pika CDN URL. All later steps must use the updated
```
video_url
```
.

If the client/host also cannot download the source bytes, stop and tell the user the host blocks direct fetch; ask them to upload the file or provide a different URL.

Outputs:

dubbed_video_url

dub_subtitles

source_subtitles

dub_transcript_srt

source_transcript_srt

source_transcript_language

Step 2 — Lipsync (state:

lipsynced_video_url

)

Default ON. Skip entirely when

--no-lipsync

is passed (then Step 3 captions

dubbed_video_url

directly).

Hard 5-minute cap — check duration before calling.

mcp__claude_ai_pika__edit_lipsync

enforces a 300-second (5-minute) audio limit upstream (sync.so) and rejects anything longer with

invalid_input

before billing; every

variant

tier shares the same cap, so falling back through tiers does NOT help. If the dubbed video's

duration_seconds

(returned by Step 1) is > 300, skip lipsync entirely, go straight to Step 3 captioning

dubbed_video_url

, and tell the user lipsync isn't available past 5 minutes (the dub itself works at any length). Only run the lipsync call below when

duration_seconds ≤ 300

Cost heads-up first. Lipsync is the dominant cost (~$4/min on the v2-pro tier). Before calling it, estimate from the dubbed video's

duration_seconds

(returned by Step 1) —

ceil(duration_seconds / 60) × $4

— and send the user a one-line heads-up, e.g. "Lipsync on — ~2 min video, est. ~$8 (pass

--no-lipsync

to skip). Starting now." Then proceed straight into the call; this is a heads-up, not an approval gate.

Call

mcp__claude_ai_pika__edit_lipsync(video_url=<dubbed_video_url>)

with no

audio_url

— the worker syncs to the dubbed video's own embedded translated audio. Do not extract the audio just to feed it back in. (

variant

defaults to

v2-pro

, with

sync-3

v2

as fallbacks.)

Outputs:

lipsynced_video_url

(read from

url

of response). When this step runs, Step 3 captions this video, not

dubbed_video_url

— otherwise the lip-matching is dropped.

Step 3 — Burn target-language captions (state:

final_video_url

)

Caption the final video so the output carries readable subtitles (matches the common "translate + subtitle" expectation). Set

caption_target_video_url

lipsynced_video_url

when lipsync ran (the default), or

dubbed_video_url

when

--no-lipsync

skipped it.

If this request is part of a Double video / split-screen comparison flow, build that Double video first and set

caption_target_video_url

to the final composed video URL. Do not burn captions onto only one panel before the Double video is composed; the bilingual caption burn should happen once, on the final visual output.

Call

mcp__claude_ai_pika__add_captions

once on

caption_target_video_url

When

bilingual_subtitles=true

, use manual bilingual mode if both tracks are available: call

mcp__claude_ai_pika__add_captions(video_url=<caption_target_video_url>, caption_mode="manual", subtitles=<dub_subtitles>, secondary_subtitles=<source_subtitles>, language=<target_language>, secondary_language=<source_transcript_language if available>, secondary_subtitles_position="below", style="branded-space-mono", position="bottom")

. The target-language (translated) row is the primary

subtitles

and renders on top; the source-language (original) row is the secondary reference and renders below it (

secondary_subtitles_position="below"

) — after dubbing the translated speech is what's actually spoken, so it leads. It works for every dub worker provider branch as long as

mcp__plugin_pika_pika__dub_video

returns both subtitle tracks.

bilingual_subtitles=true

but

source_subtitles

is missing, fall back to target-language captions only and tell the user the source transcript was unavailable from the dubbing provider. Do not invent a source-language row by retranscribing the final dubbed audio; that audio is already in the target language.

For target-language-only captions, prefer the target-language subtitles the dub worker already returned: if

dub_subtitles

is non-empty, call

mcp__claude_ai_pika__add_captions(video_url=<caption_target_video_url>, caption_mode="manual", subtitles=<dub_subtitles>, language=<target_language>, style="branded-space-mono", position="bottom")

. Manual mode skips a duplicate transcription pass and preserves the dubbing provider's target-language text.

dub_subtitles

is missing, empty, or rejected by

mcp__claude_ai_pika__add_captions

, fall back to auto: call

mcp__claude_ai_pika__add_captions(video_url=<caption_target_video_url>, caption_mode="auto", language=<target_language>, style="branded-space-mono", position="bottom")

. Auto mode re-transcribes the dubbed audio; use it only as the fallback because it costs extra time and can introduce CJK/proper-noun drift.

Use

style="branded-space-mono"

unless the user asks for a punchier style (

tiktok

hormozi

karaoke

). Skip this step only if the user explicitly asked for audio-only dubbing with no captions.

Outputs:

final_video_url

(read from

url

of response).

Step 4 — Return

Reply with

final_video_url

+ the translated transcript (from

dub_transcript_srt

/ the dub result) for user review.

Offer a bilingual-subtitle version. When this run burned target-language-only captions (

bilingual_subtitles=false

) and a source transcript is available (

source_subtitles

is non-empty), close the reply by asking whether the user also wants a dual-subtitle version, e.g. "Want a bilingual version with the original + translated subtitles stacked? I can add it." If they say yes, re-run Step 3 in bilingual manual mode on the same

caption_target_video_url

(the pre-caption visual video) — no re-dub or re-lipsync is needed, only the caption burn changes — and return the new

final_video_url

. Skip the offer when bilingual captions were already burned (

bilingual_subtitles=true

), or when

source_subtitles

is missing — without a source transcript a bilingual version can't be produced (the dubbed audio is already in the target language), so do not offer what can't be delivered.

Failure modes

Class	Trigger	Mitigation	Fallback
Source URL not worker-fetchable	`mcp__plugin_pika_pika__dub_video` returns 403 / 4xx, hotlink / UA-gated fetch failure, or "Access Denied" for a public HTTPS URL	Download source bytes in the client/host environment, `mcp__claude_ai_pika__upload_asset` them to Pika, replace `video_url` with the Pika CDN URL, then retry Step 1 once	If local download also fails, ask the user to upload the file or provide a different URL
Extra target language	Target is Cantonese ( `yue` / `cantonese` / `zh-HK` ), Thai, Hebrew, Persian, Slovenian, Catalan, Norwegian Nynorsk, or Afrikaans	Supported — call `mcp__plugin_pika_pika__dub_video` with the target as usual; the original speaker's voice is kept	Background music isn't preserved for these languages (dubbed speech only)
Dub call fails (not fetchability)	`mcp__plugin_pika_pika__dub_video` errors for another reason — unsupported target language, provider/worker 5xx, `status: failed` from `mcp__plugin_pika_pika__task_status`	Surface the error to the user; if the message points at the language, check `references/language-coverage.md` and suggest a supported tag; otherwise suggest a retry. There is no manual chain to fall back to — dub is the single path	None — return the error, do not silently produce a non-dubbed video
Dub returns no speech	Silent video — nothing to translate	Surface to user: "no detectable speech in video — nothing to translate"	None
Original voice can't be kept	For the languages above, the source is too short or noisy to keep the original speaker's voice	Surface the error and ask the user for a cleaner / longer source clip	None — the dub fails rather than using a different voice
Lipsync source too long	Dubbed video >5 min — `mcp__claude_ai_pika__edit_lipsync` rejects with `invalid_input` (sync.so 300 s cap); all variant tiers share the cap so retrying won't help	Check `duration_seconds` from Step 1 first and skip lipsync when >300; caption `dubbed_video_url` directly and tell the user lipsync caps at 5 min	Dubbed video, no lip-match
Lipsync step fails	`mcp__claude_ai_pika__edit_lipsync` errors (no clear face track, provider 4xx)	Fall back through `variant` tiers (v2-pro → sync-3 → v2); if all fail, return the dubbed video without lip-matching and tell the user	Audio-replaced video, no lip-match
Captions wrong language	Step 3 auto-transcription mis-detects language	Pass explicit `language` tag; if `dub_subtitles` exists, use `caption_mode="manual"` with it instead of auto	Manual `subtitles[]`
Bilingual source row unavailable	User asked for bilingual subtitles but `source_subtitles` is absent	Use target-language captions and explain the source transcript was unavailable	Target-language captions only

Compatibility

Primary target: Claude Code. Uses standard MCP tools only. Works on Codex / Cursor / Claude Desktop.

language-swap

NPX Install

Tags

SKILL.md Content

/pika:language-swap

Segmented / multi-language dub (per-range languages)

Behavior defaults

State variables produced and consumed

Step 0 — Parse input

Step 1 — Dub the video (state:
`dubbed_video_url`
)

Step 2 — Lipsync (state:
`lipsynced_video_url`
)

Step 3 — Burn target-language captions (state:
`final_video_url`
)

Step 4 — Return

Failure modes

Compatibility

language-swap

NPX Install

Tags

SKILL.md Content

/pika:language-swap

Segmented / multi-language dub (per-range languages)

Behavior defaults

State variables produced and consumed

Step 0 — Parse input

Step 1 — Dub the video (state: dubbed_video_url)

Step 2 — Lipsync (state: lipsynced_video_url)

Step 3 — Burn target-language captions (state: final_video_url)

Step 4 — Return

Failure modes

Compatibility

Step 1 — Dub the video (state:
`dubbed_video_url`
)

Step 2 — Lipsync (state:
`lipsynced_video_url`
)

Step 3 — Burn target-language captions (state:
`final_video_url`
)