Platform Guides

Relaycast publishes to ten networks through one request shape. You send one POST /v1/posts with shared content and media, list the accounts in targets, and add platform-specific settings in targets[].options. Each target is validated against its platform's rules before anything is queued, so content a platform would reject comes back as a 400 instead of a failed job.

Supported platforms

Document (PDF) media ("type": "document") is accepted by LinkedIn only. Sending a document to any other account returns a validation_error for that account.

Live streaming

Live Publish restreams one source (HLS, MP4, DASH, RTMP, RTSP, SRT or a media library video) to several platforms at once:

Features by platform

Scheduling is handled by Relaycast, not by the platform: a scheduled post is held in the queue and sent at scheduledFor, so every platform supports it the same way. See Scheduling.

Analytics are loaded per post from the dashboard (Posts → Analytics); see Analytics. The inbox and comment automations are covered in Inbox & Comment Automation.

How posting works per platform

1. Validation. Each target's text (its own content override, or the shared content), the shared media, and its options are checked against that platform's rules. Problems are returned per account ID in error.details.
2. Queueing. One target is created per account and one credit is charged per target.
3. Publishing. The worker downloads the media, uploads it to the platform, and records the platform's post ID and URL on the target (externalPostId, externalUrl). Temporary failures (timeouts, rate limits, 5xx) are retried with exponential backoff. Permanent failures (bad content, revoked access) mark the target failed and refund its credit.
4. Revoked access. If a platform reports that access was revoked, the account is set to reconnect_required and has to be reconnected from Integrations before it can be used again.

Connecting accounts

Every platform except Bluesky connects through OAuth from the dashboard: open Integrations, pick the platform, and approve access on the platform's consent screen. To let your own users connect from your app, use a connect link. Bluesky connects with an app password, either in the dashboard or with POST /v1/accounts/bluesky.

If you run your own deployment, each OAuth platform needs an app registered with that platform and its client ID and secret set in the environment. The redirect URI to register is:

https://social-publish-kappa.vercel.app/api/integrations/<platform>/callback

where <platform> is the platform ID from the table above (for example google_business). To use a different redirect URI for one platform, for example a public HTTPS tunnel for a platform that rejects localhost, set <PLATFORM>_REDIRECT_URI (for example TIKTOK_REDIRECT_URI). You can also connect accounts through your own platform apps; see OAuth Apps (BYOK).

META_GRAPH_VERSION optionally pins the Graph API version used for Facebook, Instagram and Instagram via Facebook Login.

Finding account IDs

targets[].accountId is the Relaycast account ID, not the platform's user ID. List your connected accounts with GET /v1/accounts:

curl https://social-publish-api.onrender.com/v1/accounts -H "x-access-key: $RELAYCAST_API_KEY"

Platform options

Each platform page has an Options section with a table generated from the same definitions the API validates against, plus a complete request example. The generic rules for targets[].options are in Platform Options.