Create a resumable upload session and receive direct PUT or multipart transfer instructions.
OAuth scope: api:write.
POST
/api/v2/knowledge/{knowledgeBaseId}/documents/uploadsX-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
Path Parameters
knowledgeBaseId*string
Unique knowledge base identifier.
Length
1 <= lengthRequest Body
application/json
Document metadata used to authorize and initialize the upload.
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
application/json
application/json
curl -X POST "https://www.sim.ai/api/v2/knowledge/string/documents/uploads" \ -H "X-API-Key: YOUR_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "workspaceId": "a91c4b2e-6d3f-4e8a-b5c7-0d9e2f1a8c64", "name": "getting-started.pdf", "contentType": "application/pdf", "size": 248913 }'{
"data": {
"session": {
"id": "string",
"knowledgeBaseId": "string",
"status": "uploading",
"name": "string",
"contentType": "string",
"size": 1,
"expiresAt": "2019-08-24T14:15:22Z",
"error": "string",
"document": {
"id": "b2d4f8a0-1c3e-4a5b-9d7c-2e6f0a8b4c12",
"knowledgeBaseId": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
"filename": "getting-started.pdf",
"fileSize": 248913,
"mimeType": "application/pdf",
"processingStatus": "completed",
"chunkCount": 24,
"tokenCount": 8123,
"characterCount": 41205,
"enabled": true,
"createdAt": "2025-06-18T16:45:00Z"
}
},
"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": "Authentication required"
}
}{
"error": {
"code": "USAGE_LIMIT_EXCEEDED",
"message": "Usage limit exceeded. Please upgrade your plan to continue."
}
}{
"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": "UNSUPPORTED_MEDIA_TYPE",
"message": "Request body must be sent as application/json"
}
}{
"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"
}
}