Provider readinessInterfaces and provider certification may evolve. Check account capabilities before production use.Read the readiness contract

Use custom video thumbnails

Attach cover images only where the provider, account, and selected placement allow them.

Direct answer

Upload a thumbnail as a separate image asset and reference it through the provider-specific video configuration exposed by the capability matrix. Preview the resolved crop and keep a fallback frame strategy for providers that generate thumbnails automatically.

What this means in practice

Upload a thumbnail as a separate image asset and reference it through the provider-specific video configuration exposed by the capability matrix. Preview the resolved crop and keep a fallback frame strategy for providers that generate thumbnails automatically.

Use the documented brand and account boundaries consistently across the scheduler, REST API, SDK, MCP tools, SSE consumers, and webhooks. That makes the same social operation explainable to an operator and reproducible by an integration.

Implementation checklist

  1. Create a high-quality image asset with safe text margins and accurate subject framing.

  2. Check whether the account allows a custom thumbnail for the selected video surface.

  3. Validate dimensions, aspect ratio, and maximum file size.

  4. Preview small and large display contexts before approval.

  5. Retain a video frame fallback when the provider ignores or rejects custom covers.

Operational details

Thumbnail support may exist for one surface and not another on the same provider.

The media library can reuse a thumbnail across compatible posts, but each target still validates it.

A cover should accurately represent the video and follow the provider's content policies.

Common mistakes to avoid

Protect intent, tenant boundaries, and provider state.
  • Do not assume the provider will preserve the entire image without cropping.
  • Do not place critical text at the extreme edges.
  • Do not misrepresent the video content with unrelated clickbait imagery.

Was this useful? This documentation is reviewed against the public App9 Post contract. Use the API reference and live capability response for machine-enforced details.

Open API reference