Synthesia
Move briefs, assets and sign-offs through Synthesia without chasing between tools.
7 ways to read, 2 ways to write, each write switched on by you.
Quality checks
Built and tested with example responses.
- Ready to connect: doneEvery listed action is built in.
- Built and tested with example responses: doneEach action is built from the provider’s published API and tested against example responses, errors, rate limits and paging.
Connected, approved, proven.
The things teams do most with Synthesia, an example flow with a person in the loop, and what Nexra keeps as proof.
Top actions
- Create video from templateApproval by rule
- Create videoApproval by rule
- List templatesRead
Example flow
- Synthesia · List templatesDone
- Synthesia · Create video from templateNeeds approval
- Nexra · Record the decision and result in the evidence chainProven
Example workflow. Routine runs go through on their own. Only a change your rules flag, such as one over a limit you set, waits for the right person, who sees the exact change and the rule before it reaches Synthesia.
What gets logged
- Whether it ran on its own or who approved it, and under which rule
- A fingerprint of the exact request sent to Synthesia
- Synthesia's reply: what it created or changed
- One entry in the evidence chain, linked to the one before
Try this in the sandbox
Run the whole flow with test data in your sandbox, then connect your own account when you are ready to go live.
For developers
Technical detail
Read Synthesia videos, templates, translations and webhooks, and create private AI avatar videos from templates or scripts (billable; test mode by default).
Synthesia API docs- Source actions
- 7
- Destination actions
- 2
- Data types
- 5
What you can map
Reads are always available. Writes are off until you switch them on for a connection, and governed writes follow your policies.
Template videos1
- Create video from templateDestinationNot retried automaticallyApproval before production
Render a private video from a template, replacing its variables. Billable unless Test mode is on (the default). Poll Get video for status.
Templates2
- Get templateSource
Get a template and the variables available for customisation.
- List templatesSource
List Synthesia and workspace templates with the variables each accepts.
Video translations1
- Get video translationsSource
Get the translation status for each language of a video.
Videos3
- Create videoDestinationNot retried automaticallyApproval before production
Render a private video from scripted scenes (avatar, background and script per scene). Billable unless Test mode is on (the default).
- Get videoSource
Get a video's rendering status, duration and time-limited download URL. Poll this after creating a video.
- List videosSource
List videos created via the API or in Synthesia, with status and download links.
Webhooks2
- Get webhookSource
Get one webhook subscription's URL and status (the secret is not returned).
- List webhooksSource
List the webhook subscriptions configured for the API key owner (secrets are not returned).
Access and limits
- Authentication
- Synthesia API key (Authorization header)
- Plans and access
- Synthesia Creator plans and above (Creator and Enterprise API tiers). API keys belong to the user who created them, not the workspace. Use a Legacy (v2)-scoped key. Video minutes are drawn from the plan; test videos are free but watermarked and limited to 30 a day.
- Test environment
- There is no sandbox. Use test mode (test: true), which Nexra sends by default, to render free watermarked videos.
- Rate limits
- Per endpoint by API tier: Creator 60 requests a minute (writes also 300 an hour and 1,000 a day; reads 20,000 a day); Enterprise tiers up to 120 a minute. HTTP 429 carries RateLimit-Limit and RateLimit-Reset (seconds). Test videos are limited to 30 a day.
- Pagination
- Videos, templates and webhooks use limit (max 100) and offset; every page returns nextOffset, which Nexra follows while a full page is returned.
- Provider events
- Synthesia webhooks for video.completed and video.failed (and dubbing events), signed with a per-webhook secret. Webhooks are created per API key owner. Flows run on demand, on a schedule, or when a scheduled check finds new or changed records.
Before you build a flow
- Create video and Create video from template are billable unless Test mode is on: real renders consume the plan's video minutes. They are never retried automatically and Synthesia documents no idempotency key, so a timed-out request may still have created a video; check List videos before repeating it.
- Videos are always created private: visibility is fixed to private, so no public share page is created. Update a video (which can make it public), call-to-action buttons and share pages are not exposed.
- Test mode defaults to true. Set it to false explicitly for a production render.
- The rendered MP4 is not downloaded: Get video returns a time-limited download URL. Binary upload and download (assets, script audio, dubbing sources) is an engine gap.
- Create video accepts avatar, background, script text and basic avatar settings per scene. Script audio uploads, background video settings, soundtracks and per-scene sound settings are not exposed.
- Excluded by design: deleting videos and webhooks, creating webhooks, assets and script audio uploads, dubbing, XLIFF import and translation start.
- Callback IDs are refused when they contain an email address; Synthesia's docs suggest emails, but Nexra keeps personal data out of video metadata.
- HTTP 429 reports RateLimit-Reset rather than Retry-After, so Nexra backs off with its default schedule.
- No updated-since filter is documented for videos or templates.
Developer reference
- Create the Synthesia credentials described above with the narrowest permissions your flows need.
- In Nexra, open Connect, then Connections, then New connection, choose Synthesia, enter its settings and credentials, and tick only the write actions you need. Connection guide
- Test the connection, then use its actions as flow sources and destinations. Flow guide
Machine-readable detail: GET /api/public/connect/connectors/synthesia and the Connections API.