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Midjourney
Action (Upscale, Variation, Reroll, Zoom)
Use CometAPI POST /mj/submit/action to apply Midjourney actions—upscale, variation, reroll, zoom, and more—on images generated via imaging.
POST
/
mj
/
submit
/
action
Create a Midjourney follow-up action task
curl --request POST \
--url https://api.cometapi.com/mj/submit/action \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"customId": "MJ::JOB::variation::3::example",
"taskId": "1773314942177684"
}
'{
"code": 123,
"description": "<string>",
"result": "<string>",
"properties": {
"numberOfQueues": 123,
"discordInstanceId": "<string>",
"discordChannelId": "<string>"
}
}Use this endpoint after a Midjourney task returns action buttons. It starts a new downstream task such as upscale, variation, reroll, zoom, or pan.
You need two values
taskIdfrom the original or most recent Midjourney taskcustomIdfrom the latestbuttonsarray returned by Fetch Single Task
customId is not stable. Never hardcode it. Always read it from the latest polling response.Common actions
U1toU4: upscale one image from the gridV1toV4: generate variations from one image position- Reroll: regenerate the full grid
- Zoom and Pan: extend the existing composition
After you submit an action
Poll the new task
Query Fetch Single Task again until the action finishes.
Handle modal-only actions
If the new task reaches
MODAL, continue with Modal to supply the extra input.Authorizations
Bearer token authentication. Use your CometAPI key.
Body
application/json
Action id taken from the latest buttons array returned by the fetch endpoint.
Midjourney task id you want to continue from.
Custom state string. Returned as-is in the task result and webhook callback for your own tracking.
Whether to force remix mode when the current action supports it.
Whether to prefer the same channel account used by the current task.
⌘I
Create a Midjourney follow-up action task
curl --request POST \
--url https://api.cometapi.com/mj/submit/action \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"customId": "MJ::JOB::variation::3::example",
"taskId": "1773314942177684"
}
'{
"code": 123,
"description": "<string>",
"result": "<string>",
"properties": {
"numberOfQueues": 123,
"discordInstanceId": "<string>",
"discordChannelId": "<string>"
}
}