Seedream 5.0 Lite: Image-to-Image API
ByteDanceimage$0.035 / runSubmit a Seedream 5.0 Lite: Image-to-Image run over HTTP, then poll it or take a webhook. Results are files on media.ezflows.io. Try it in the playground first.
Async: the POST answers at once with a request id. Poll it, or take the webhook.
- 01
Submit
Parameters at the top level of the JSON body. Answers 202 with a request id.
curlPOST /v1/models/seedream-v5-lite-image-to-image curl -X POST https://api.ezflows.io/v1/models/seedream-v5-lite-image-to-image \ -H "Authorization: Bearer $EZFLOWS_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "prompt": "a wide shot of a desert at dusk", "aspect_ratio": "16:9", "size": "3K" }' # 202 Accepted, at once — it never waits for the model: # {"request_id": "req_8f2a41c9b70e4d15", "status": "queued", # "poll_url": "https://api.ezflows.io/v1/requests/req_8f2a41c9b70e4d15"} - 02
Poll
Same bearer header, every few seconds, until the status is final.
curlGET /v1/requests/:id REQUEST_ID=req_8f2a41c9b70e4d15 # from the POST while :; do BODY=$(curl -s https://api.ezflows.io/v1/requests/$REQUEST_ID \ -H "Authorization: Bearer $EZFLOWS_API_KEY") STATUS=$(echo "$BODY" | jq -r .data.status) case "$STATUS" in succeeded|failed|cancelled) break ;; esac sleep 3 done echo "$BODY" | jq -r '.data.output.artifacts[].url' # media.ezflows.io, kept 90 days - 03
Response
Files are on media.ezflows.io, kept 90 days. A failed run says why and costs nothing.
json200 · succeeded { "data": { "id": "req_8f2a41c9b70e4d15", "model_slug": "seedream-v5-lite-image-to-image", "status": "succeeded", "http_status": 200, "cost": 0.035023, "auth_method": "api_key", "error": null, "submitted_at": "2026-09-12T18:07:21.114Z", "queue_started_at": "2026-09-12T18:07:21.402Z", "execution_started_at": "2026-09-12T18:07:22.010Z", "first_byte_at": "2026-09-12T18:07:52.871Z", "finished_at": "2026-09-12T18:07:55.203Z", "io_deleted_at": null, "canvas_id": null, "canvas_node_id": null, "client_attempt_id": null, "idempotency_key": null, "input": { "prompt": "a wide shot of a desert at dusk", "aspect_ratio": "16:9", "size": "3K" }, "output": { "artifacts": [ { "index": 0, "kind": "image", "contentType": "image/png", "url": "https://media.ezflows.io/outputs/<account>/req_8f2a41c9b70e4d15/0.png" } ] } } } - 04
Webhook
Skip polling: we POST the result to your endpoint, at least once.
- Register
- Create an endpoint under Webhooks in the dashboard; the signing secret is shown once.
- Events
- request.succeeded · request.failed · request.cancelled
- Headers
- ezflows-event-id (dedupe on it) · ezflows-timestamp (unix seconds) · ezflows-signature t=<ts>,v1=<hex HMAC-SHA256 of "<ts>.<raw body>">
- Verify
- Over the exact bytes received, in constant time; reject anything older than five minutes.
- Respond
- Any 2xx within 10 s. Redirects are not followed.
- Retries
- Five, with backoff: 30 s · 60 s · 2 min · 4 min · 8 min. Disabled after five consecutive dead deliveries.
jsonDelivery body { "id": "82cf46a4-841e-41d6-b3c7-facc937d3252", "type": "request.succeeded", "created_at": "2026-09-12T18:07:55Z", "data": { "id": "req_8f2a41c9b70e4d15", "model_slug": "seedream-v5-lite-image-to-image", "status": "succeeded", "cost": 0.035023, "output": { "artifacts": [ { "url": "https://media.ezflows.io/…/0.png" } ] } } }curlverify.sh # Create the endpoint under Webhooks in the dashboard; the signing secret is shown once. # ezflows-signature: t=<ts>,v1=<hex HMAC-SHA256 of "<ts>.<raw body>"> # body.json = the exact bytes received. Reject anything older than five minutes. EXPECTED=$({ printf '%s.' "$TS"; cat body.json; } \ | openssl dgst -sha256 -hmac "$EZFLOWS_WEBHOOK_SECRET" -r | cut -d' ' -f1) [ "$EXPECTED" = "$V1" ] && echo "valid" || echo "reject"
Parameters 6
| Name | Type | Default | Allowed | Description |
|---|---|---|---|---|
| promptrequired | string | — | — | Describe the desired image transformation or style change. |
| image_input | string[] | — | image urls | Input images to guide creation, Upto 10 Images for reference. |
| aspect_ratio | enum | 16:9 | 1:1 · 4:3 · 3:4 · 16:9 · 9:16 · 3:2 · 2:3 · 21:9 | Image aspect ratio. 16:9 for widescreen, 1:1 for square. |
| size | enum | 3K | 2K · 3K | Image resolution. 2K for moderate detail, 3K for fine detail. |
| max_images | integer | 1 | — | Number of images to generate. Use 1 for single output. |
| optimize_prompt | enum | fast | standard · fast | Select optimization mode: 'fast' for quicker results, 'standard' for detailed transformation. |
File inputs (image_input: image urls) take URLs. Upload the raw file to POST /v1/uploads with its own Content-Type and pass the url it returns. Inputs are kept 90 days.