Underlord (beta): Your AI co-editor in Descript

Underlord is Descript’s AI co-editor built specifically for video editing. Just say (type) what you want, and Underlord handles it. Even if you don’t know exactly what you’re looking for, Underlord can help you get to the finish line.

It's an agentic co-editor, meaning Underlord can act on your behalf. So instead of giving you a one-off suggestion, it takes initiative.

Usage note

On current plans, this feature uses AI Credits. Learn more about tracking your Media Minutes and AI Credits.

Legacy and Sunset plans track usage differently. See our Understanding your Legacy and Sunset plan guide for details.

How do I open / where is Underlord?

Open any project, click the Underlord icon in the right-hand sidebar, and start chatting with Underlord.

Choose your model

Choose which model powers Underlord by clicking the model selector (the cube icon) near the bottom of the Underlord chat window. Premium models are available on paid plans.

Model picker interface in Descript showing available AI model options

How Underlord uses AI credits

Each prompt uses credits for Underlord's reasoning (the "agent brain"). When Underlord runs a tool or applies an effect on your behalf you'll be charged for both the agent brain and the tool itself.

Underlord is also non-deterministic: the same prompt can cost different amounts on different runs. All of these costs show up under "Underlord" in your Usage tab. For the full picture, see Track and understand your media minutes and AI credits.

Model	Overview
Auto	Smart model selection that automatically chooses the best AI for each task based on your request.
Claude Haiku 4.5	Fast and efficient for quick edits, summarization, and everyday writing tasks. Ideal when you want responsive, concise help from Underlord without long processing times.
Claude Sonnet 4.6	Suited to creative workflows, multi-step tasks, and editing where instruction-following matters most.
Claude Opus 4.6 Claude Opus 4.7 Claude Opus 4.8	Strong reasoning and nuanced language generation. Works well for complex editing suggestions, detailed rewrites, or creative tasks that require a deeper understanding of context.
GPT 5.4 / 5.4 Thinking	A fast, reliable model for straightforward editing tasks.
GPT 5.5	Suited for interactive edting tasks
Gemini 3.1 Pro	Works well for complex, text-heavy work that needs deeper reasoning and more careful instruction following.
Gemini 3.5 Flash	Faster model suited to everyday tasks, larger volumes of work, and quick multi-step edits.

What can Underlord do?

Ask Underlord to help with nearly any editing goal. While we provide a few examples below, the possibilities are endless, and we encourage exploration. If you don’t see it here—try it anyway, and see what happens.

What Underlord can do	Example prompts
Captions	Add viral, social media-style captions to my video. Emphasize the active spoken word in my brand color yellow #ffd02b. Add captions for all the clips. Update this clip so the captions follow this format: Manrope font, 100pt, extra bold, centered white text with a 30pt black shadow. Active word in yellow with a 10pt black outline. Future words in transparent white. Semi-transparent black background behind the playhead.
Clips	Can you split this into 5 clips that are max 1 minute long? Find me clips for social media that are between 60–90 seconds long and reformat them for vertical aspect ratio.
Animations & Transitions	Add a left to right pan animation to the image layer. Add zooms to moments of emphasis. Add a simple fade-out effect to the end of this video. Fade out the clip at the end. Add zoom cuts every 3 to 6 seconds. Apply animated callouts to important words in the scene.
Translate	Translate the subtitles to Japanese. Translate this video from Spanish to English with captions.
Sound Effects & Music	Apply reverb on the script track with 30% damping. Apply Studio Sound with 70% intensity. Lower audio on other layers to make my speech stand out.
Slides to Video	Summarize the key points from these slides and make a 1-minute video. Take this document and this PDF of slides and turn it into a video about my company strategy, using the slides as b-roll. Use the text on each slide as the script for TTS, and turn it into a narrated video. Use an avatar and generated media to help tell the story.

Looking for AI Tool buttons?

Tools like Remove Filler Words, Shorten Word Gaps, and Edit for Clarity are now part of the AI tools panel. You can still use them manually — or ask Underlord to take care of them for you as part of a prompt. Learn more about manually applying AI tools.

How to leave feedback

Underlord is still in beta, and we’re actively improving it. Try bold prompts, mix tasks together, and find out just how capable your new co-editor is.

Try it out and let us know how it’s going. Click the thumbs up or thumbs down icon in the action bar below Underlord's response, and drop us a note with your thoughts.

What to expect when working with Underlord

Descript’s AI features, including Underlord, are powered by large language models that can do remarkable things, but they’re still learning and sometimes get things wrong.

These tools are designed to be helpful, fast, and flexible, but they don’t always know when they’re out of their depth. At times, Underlord might overpromise, make incorrect assumptions, or follow you into workflows it's not equipped to complete. That can be frustrating, especially when you’re on a deadline or expecting hands-off results. We understand.

We’re actively working to improve both the AI’s honesty and its humility. This means adding better safeguards so the agent doesn’t agree to do things it can’t actually deliver, and making it more transparent about its current limitations.

In the meantime, Underlord works best when treated like a fast, talented collaborator who still needs clear instructions, context, and regular check-ins. For example, it can’t make edits in the background while you’re recording—it needs your narration or script in place first. And when you ask it to do something complex, it helps to check its work and give feedback as you go. Point Underlord at specific scenes, layers, or script passages to give it the context it needs.

AI isn't magic, but it is a powerful creative partner when used thoughtfully. As we continue improving Underlord, your experiences—good and bad—help shape its future. If you run into issues or have suggestions, we’d love to hear from you. Thanks for building with us.