Create a resumable upload session and receive either a signed PUT URL or multipart instructions.
POST
/api/v2/files/uploadsAuthorization
apiKey X-API-Key<token>
Your Sim API key, personal or workspace-scoped. Generate one under Settings, then API Keys. Operations that reject workspace keys say so in their own description.
In: header
Request Body
application/json
File metadata required to create an upload session.
TypeScript Definitions
Use the request body type in TypeScript.
Response Body
application/json
application/json
application/json
application/json
application/json
application/json
application/json
application/json
application/json
curl -X POST "https://www.sim.ai/api/v2/files/uploads" \ -H "X-API-Key: YOUR_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "workspaceId": "string", "name": "string", "contentType": "string", "size": 0 }'{
"data": {
"session": {
"id": "string",
"status": "uploading",
"name": "string",
"contentType": "string",
"size": 0,
"expiresAt": "2019-08-24T14:15:22Z",
"error": "string",
"file": {
"id": "wf_V1StGXR8z5jdHi6BmyT91",
"name": "data.csv",
"size": 1024,
"type": "text/csv",
"key": "workspace/example/data.csv",
"folderPath": "string",
"uploadedByEmail": "jane@example.com",
"uploadedAt": "2026-01-15T10:30:00Z",
"updatedAt": "2026-01-15T10:30:00Z",
"deletedAt": "2026-01-16T09:00:00Z"
}
},
"uploadToken": "string",
"transfer": {
"method": "put",
"url": "http://example.com",
"headers": {
"property1": "string",
"property2": "string"
},
"expiresAt": "2019-08-24T14:15:22Z"
}
}
}{
"error": {
"code": "BAD_REQUEST",
"message": "Invalid request"
}
}{
"error": {
"code": "UNAUTHORIZED",
"message": "API key required"
}
}{
"error": {
"code": "FORBIDDEN",
"message": "Insufficient workspace permissions",
"details": {
"code": "INSUFFICIENT_WORKSPACE_ROLE"
}
}
}{
"error": {
"code": "NOT_FOUND",
"message": "Not found"
}
}{
"error": {
"code": "PAYLOAD_TOO_LARGE",
"message": "Request body is too large"
}
}{
"error": {
"code": "RATE_LIMITED",
"message": "API rate limit exceeded",
"details": {
"retryAfter": "2026-01-01T00:00:30.000Z"
}
}
}{
"error": {
"code": "INTERNAL_ERROR",
"message": "Internal server error"
}
}{
"error": {
"code": "SERVICE_UNAVAILABLE",
"message": "Service temporarily unavailable"
}
}