# Synthesia setup for PopMCP You paste one value into PopMCP: a Synthesia API key, made under Developers in Synthesia with the right scopes ticked. - Auth: API credentials - Setup time: 2 min - Credentials screen: https://app.synthesia.io/ - Provider docs: https://developers.synthesia.io/docs/scopes ## Approval required before this works No one reviews you, but making videos through the API needs a Pro plan or above, because your plan decides which scopes a key can have. Dubbing through the Localization API works on every plan. - Typical wait: None. A plan change applies as soon as you make it. - Cost: Synthesia's Pro plan, shown at $89 a month or $59 a month billed yearly in October 2026, plus the credit each video and dub uses. PopMCP adds nothing to this. - Blocked until approved: Videos, templates, webhooks, uploads and translations, which all need the Legacy (v2) scope. Audit logs and XLIFF need Enterprise. - Works meanwhile: On any plan, make a key with Localization (write) and connect it. Your AI can then read your credit balance and dub videos while the workspace has credit. ## Before you begin - A Synthesia account. Making videos through the API needs a Pro plan or above. Dubbing through the Localization API works on every plan - Credit in the workspace, if your AI will make real videos or dub them. Free test videos and reading your videos need none ## Get your credentials ### 1. Open Developers in Synthesia Sign in to Synthesia and select Developers in the sidebar, then the API keys tab. A key belongs to the workspace you are in, so switch to the right workspace first. To work in another one later, connect it with its own key. Screen: https://app.synthesia.io/ ### 2. Make a key for PopMCP Select New API key and name it PopMCP. Under Scopes, tick Legacy (v2) for videos, templates, webhooks and uploads, and Localization (write) for dubbing. Tick Interactive Avatars (write) if you use live avatars. Your plan decides which ones you can tick. Under Expires, pick a longer time or Never: the default is 30 days, and your connection stops when the key expires. Then select Create API key. Screen: https://app.synthesia.io/ ### 3. Copy the key right away Copy the key as soon as it appears. Synthesia only shows it in full once. If you lose it, delete it and make a new one. ### 4. Paste the key into PopMCP In PopMCP, paste the key into API key and connect. PopMCP tries your videos, your dubbing languages and your credit balance with free reads, and tells you if a scope is missing. New connections start read-only, so your AI can look at your videos and templates but cannot make anything or spend credit until an owner or admin allows write actions. ## Fields PopMCP asks for - API key (apiKey) [required]: In Synthesia open Developers, then API keys, and choose New API key. Copy it right away, because it is only shown once. Stored encrypted and used only on our servers. ## Verify PopMCP marks the Synthesia connection Verified and notes any scope the key is missing. Asking the AI how many credits you have left, then to list your videos, returns real results at no cost. ## Troubleshooting ### "Synthesia did not accept this API key..." Cause: The key was copied incompletely, or it has been disabled or deleted. Synthesia also disables a key when the person who made it leaves the workspace. Fix: Open Developers, then API keys, in Synthesia and make a new key. It is only shown in full once. ### "This Synthesia API key has expired..." Cause: Keys expire on the date chosen when they were made. The default is 30 days. Fix: Make a new key with a longer time or Never, and connect it in PopMCP. ### "This key cannot reach videos or dubbing..." Cause: The key has neither the Legacy (v2) nor the Localization scope, or your plan does not allow them. Fix: Under Developers, then API keys, choose Edit key on this key and tick the scopes. Legacy (v2) needs a Pro plan or above. You do not need a new key for this. ### Videos answer 403, but dubbing works Cause: The key has a Localization scope but not Legacy (v2). The two are separate: neither covers the other. Fix: Tick Legacy (v2) under Edit key. Asking the AI to check the key's access shows which parts it can reach. ### The AI says it cannot make a video Cause: The connection is read-only, which is how every new connection starts. Making a video can spend credit, so it counts as a write. Fix: Have an owner or admin allow write actions on the connection in PopMCP. ### The video has a watermark Cause: PopMCP's video tools make a free test unless told otherwise. Tests carry a watermark and are limited to 30 a day. Fix: Once you are happy with it, ask the AI to make the final version without test mode. That one spends credit. ### A video stays in progress for a long time Cause: Rendering takes a few minutes, and a finished video stays in progress while it passes moderation review. Fix: Ask the AI to check on it again. It keeps the same video, so nothing is started twice. ### A download link no longer opens Cause: Synthesia's download links are time-limited. Fix: Ask the AI to get the video again. A fresh read gives a new link. --- Source: https://www.docs.popmcp.com/docs/integrations/synthesia/