Report which slot a create would take for a field type, and how many are left. Advisory rather than a claim: nothing is reserved, and POST /api/v2/knowledge/{knowledgeBaseId}/tags assigns the same slot when tagSlot is omitted. A workspace API key is rejected with 403; use a personal API key.
/api/v2/knowledge/{knowledgeBaseId}/tags/next-slotAuthorization
apiKey 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
Unique knowledge base identifier.
1 <= lengthQuery Parameters
Workspace that owns the knowledge base.
1 <= length <= 128Value type stored in the slot; it decides which slots are usable and which filter operators apply. Slot capacity per type: text 7, number 5, date 2, boolean 3.
"text" | "number" | "date" | "boolean"Response Body
application/json
application/json
application/json
application/json
application/json
application/json
application/json
application/json
curl -X GET "https://www.sim.ai/api/v2/knowledge/string/tags/next-slot?workspaceId=string&fieldType=text" \ -H "X-API-Key: YOUR_API_KEY"{
"data": {
"nextAvailableSlot": "tag3",
"fieldType": "string",
"usedSlots": [
"string"
],
"totalSlots": 1,
"availableSlots": 0
}
}{
"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": "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"
}
}