PricingChoose what the brief is allowed to change
A rough idea invites a tool to propose a script. An approved script asks it to preserve wording. A footage brief asks it to select and arrange recorded material. Separate these instructions before comparing products: a polished video can still fail by rewriting an approved claim or inventing a product detail.
Shorty publishes this guide and appears in the comparison. The descriptions below come from the linked product pages and help documentation, reviewed on 5 October 2026. They are documented workflows, not a hands-on quality or speed ranking.
Compare the input and the review surface
Use the row that matches the work you need to finish. Several products support more than one starting point.
| Product | Useful starting material | What to evaluate |
|---|---|---|
| Shorty | Your footage plus a brief or optional reference | Source selection, treatment, written revisions and the rendered MP4 |
| Synthesia | A prompt, approved script or source document | Script handling, storyboard changes and the required plan |
| HeyGen | A script, product information or brief | Presenter choice, brand details, scenes and localization |
| InVideo | A concept, script or campaign direction | The agent’s plan, generated assets and editable sequence |
| Runway | Creative direction with optional reference or source assets | Generation choices, credit estimates and multi-clip timeline refinement |
| Adobe Firefly | A shot description, image or existing clip | Generated imagery, camera direction and further editing |
Sources: Shorty: supplied-footage workflow · Synthesia: creation entry points · HeyGen: marketing brief workflow · InVideo: agentic filmmaking · Runway: Agent and timeline · Adobe: generation and editing. Feature descriptions checked 5 October 2026.
Preserve an approved script deliberately
Synthesia’s creation documentation distinguishes importing a script from importing a file. The script route preserves the supplied wording; the file route creates a new script from the material. A document that happens to contain approved copy therefore needs the correct entry point. Check the resulting text before rendering.
For any tool, separate exact copy from creative notes. Keep the approved product name, offer and ending in one clearly marked block. Put pacing, visual style and optional ideas elsewhere. Compare the output line by line with the approved version, including captions and narration.
VEED’s project guide similarly separates a prompt, which creates a script to review, from its Script tab, which uses supplied text as written. Choose the intended input mode and still check the spoken and displayed result; a text box alone does not tell you whether the wording will be rewritten.
Sources: Synthesia: exact script versus rewritten source material · VEED: prompt versus exact-script project entry. Feature descriptions checked 5 October 2026.
Check a drafted script before producing its scenes
For a new script, provide the audience, one intended takeaway, target duration and a short example of your own speaking style. Descript’s script template asks for this context; Kapwing’s guidance also separates script refinement from scene generation. Read the draft aloud, time that reading and correct product names and factual claims before paying to generate visuals.
A useful script review pairs each spoken beat with its intended image. If a line promises a result your footage cannot show, change the line or supply the missing evidence. Keep approved wording separate from the instructions that may be rewritten.
Sources: Descript: script context and spoken delivery · Kapwing: script and visual review. Feature descriptions checked 5 October 2026.
Keep the agent’s first cut editable
InVideo’s current help describes a browser timeline where agents can assemble uploaded footage and where you can continue adjusting clips, audio and color by hand. Its documentation also describes exporting a sequence to professional editors. Test the receiving editor with your own media, titles and audio before relying on that handoff.
Kapwing’s Kai can accept supporting media, prepare a storyboard and assemble a project. Its help recommends checking the plan and credit estimate before generation, then using Studio for precise changes such as subtitle styling or duration. A storyboard approval and a satisfactory finished export are separate checkpoints.
Sources: InVideo: uploaded footage, timeline and export · InVideo: brief, agent and editing workspace · Kapwing: storyboard, credit estimate and manual finishing. Feature descriptions checked 5 October 2026.
Approve a scene plan before generating the full campaign
Use a short scene plan with one job per scene: establish the problem, show the action, explain the result and give the next step. Assign a source clip, approved asset or explicitly generated illustration to each scene. This exposes missing material before it becomes an expensive revision.
Synthesia’s Storyboard can change scene order and layouts while retaining script content. Runway Agent can explain its generation plan and, when configured to ask first, show the model, prompt and estimated credit use before generating. In either workflow, inspect the proposed plan and the actual result separately; approval of an idea does not prove the output follows it.
Sources: Synthesia: script and scene review · Runway: planning and generation controls. Feature descriptions checked 5 October 2026.
Check how scenes stay consistent
LTX Studio describes breaking a script into scenes and shots and creating reusable Elements for characters, objects and locations. Review those assets before generating the sequence. Confirm what the exported file represents: an early storyboard for approval and a finished campaign video serve different purposes.
Frameloop describes script generation followed by scene-by-scene changes to visuals, timing and flow. Test continuity with a specific correction: replace one scene while retaining the same product appearance and narration in the neighboring scenes. A reusable asset or an editable scene is a useful control, but the exported result still needs inspection.
Sources: LTX Studio: shot breakdown and reusable Elements · Frameloop: script-to-video and scene revision. Feature descriptions checked 5 October 2026.
Check which tool receives the script
Canva’s cited script-to-video workflow uses the HeyGen app for a talking avatar, then Canva for further design changes. It requires a HeyGen sign-in and has its own usage limits. This differs from Canva’s tools for generating imagery or assembling uploaded clips. Check the named app and its allowance before assuming your design subscription covers the whole workflow.
Vmaker presents several separate routes: text to avatar video, documents to video, audio to visuals, and editing or shortening existing recordings. Choose the route matching your source, then test its correction controls. A platform supporting all these inputs does not mean every input follows the same creation or review process.
Sources: Canva: script-to-video with the HeyGen app · Vmaker: text, document, audio and recorded-video workflows. Feature descriptions checked 5 October 2026.
Write shot instructions at the right level
A campaign brief explains the audience and intended message. A shot prompt explains what appears in one scene and how it moves. Keep both available. For a generated insert, specify the subject, action, setting and camera treatment. When an input image already establishes the appearance, focus the accompanying direction on motion.
For a filmed demonstration, preserve the real action instead of asking a generator to invent proof. In Shorty, supply the clips that show the result and state which actions must remain complete. A reference can direct pacing without becoming the source of the product footage.
Sources: Runway: scene and motion prompts · Runway: motion from an input image. Feature descriptions checked 5 October 2026.
Review one correction before expanding the batch
Ask for a meaningful change: replace a scene while preserving the approved wording and ending. Check that the product still looks right, the narration remains accurate and the other scenes stay intact. Record the credits, manual work and review needed to approve that second version.
Then create the remaining formats or variants. Tie each file to its brief, source assets and approval state. Review the exported version at its intended size, especially text, crops, dates and the call to action. A finished render becomes a finished marketing deliverable only after it passes those checks.
Check the specific product behind a familiar name
Agent Opus describes a brief- and script-to-video workflow that assembles visuals, narration and motion graphics. Evaluate that route separately from OpusClip’s long-video clipping and talking-head AI Producer workflows. Use your actual script and brand assets, then inspect the proposed scenes and final export.
A marketplace listing can also describe a separate provider. Canva’s cited AI Video Generator app is by Imgkits and lists its own developer, policies and design permissions. Check the named app, provider and account allowance instead of assuming every video tool inside Canva is the same built-in feature.
Sources: Agent Opus: script-driven production · Canva: Imgkits app listing. Feature descriptions checked 5 October 2026.