What you say to the agent
No special syntax — just describe it like you would to a person.
What it does, step by step
- 1
Give the agent the video and the audio track (music, voiceover, SFX, or generated speech).
- 2
Choose replace (strips the original audio, substitutes yours) or mix (keeps the original and layers your audio underneath, with volume controls).
- 3
It combines them — the video stream is copied losslessly, so this is fast.
What it needs from you
- •A video to work from
- •An audio clip to work from
What comes back
The video with the new audio attached (replaced or mixed in, as you chose).
What it costs
A flat credit fee regardless of the video's length.
Under the hood
This is what the agent actually calls when you ask for it — real tools from its live surface, not marketing copy.
attach_audio_to_videoAttach an audio file to an existing video. Use when the user has a generated/uploaded video AND a separate audio track (music, voiceover, SFX, generated speech) and wants them combined. Two modes: (A) 'replace' (default) — strips the video's original audio and substitutes the supplied audio. Pick this when the user says 'replace the sound', 'mute the original', 'put this music on the video', or any time the supplied audio should be the only audible track. (B) 'mix' — keeps the original video audio AND mixes the new audio on top, with separate volume controls. Pick this when the user wants background music UNDER existing voice/SFX (e.g., 'add background music', 'put music behind my talking video'). Video stream is copied losslessly (no re-encode of visuals). Fast. Costs a flat credit fee regardless of length.
See it done in a real workflow
Morning Matcha Routine
UGC-style wellness reel — a clean-girl creator walks through her actual morning matcha ritual, then cuts to a cozy animated hero shot of the finished iced latte.
TrendingNYC Street Interview
Photorealistic street-vlog interview — Riley works three different NYC corners at golden hour asking strangers one question: "What's the wildest thing you've ever done?" Three candid OTS/two-shot clips with locked character references, real handheld energy and native spoken dialogue. Vertical 9:16.
TrendingPrimo Protein vs Other Brand
Pixar-style 3D comparison ad — the confident PRIMO PROTEIN pouch faces off against the tired old rival brand's tub across 11 talking clips: pasture vs dusty pantry, herb garden vs toxic lab, clean American lab vs grimy factory, chocolate-milkshake CTA vs "wet sand." ~40s vertical reel with native character voices.
Or start from a one-tap template
Frequently asked questions
What do I actually say to the agent to add music or a voiceover to a video?+
Just describe it in plain English — for example: "Put this music track on this video and mute the original audio" The agent handles picking the right tool and model from there.
What does the agent need from me first?+
At minimum: A video to work from; An audio clip to work from. Anything else it needs, it asks for before running.
What do I get back?+
The video with the new audio attached (replaced or mixed in, as you chose).
Does this cost credits?+
A flat credit fee regardless of the video's length.
You can also just ask for
Ask your Versely agent to add music or a voiceover to a video
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