SAP CC Autoscaling (Castellum)
Inspect Castellum autoscaling state: view resource configurations, check pending resize operations, diagnose failed scaling actions.
MCP Tools
Note: Castellum MCP tools are planned but not yet implemented in the MCP server. The skill documents the service for reference. When tools become available, they will follow the
castellum_prefix pattern.
Expected Tools (NOT YET AVAILABLE)
| Tool | Purpose | Expected Parameters |
|---|---|---|
castellum_list_resources |
List autoscaling-managed resources | project_id |
castellum_get_resource |
Get autoscaling config for a resource | asset_type, asset_id |
castellum_list_operations |
List scaling operations history | asset_type, state |
Interim Workaround
Until Castellum MCP tools are available:
- Use
maia_querywith PromQL to check Castellum metrics:castellum_resource_* - Use
hermes_list_events(target_type=autoscaling/resource)for scaling audit trail
Gotchas
project_id must be a valid UUID. The tool validates UUID format and rejects anything else. You cannot pass a project name — resolve it to UUID first via Keystone if needed.
asset_type uses a colon-separated hierarchy. Format is
project-quota:<service>:<resource>, e.g.,project-quota:compute:coresorproject-quota:network:floating_ips. Getting this format wrong returns empty results without an error.Castellum watches Limes, does not replace it. Castellum monitors usage via Limes and triggers resize operations. The actual quota values live in Limes. To see current quota/usage, use
limes_get_project_quota. Castellum shows the autoscaling configuration and pending/failed operations.Pending does not mean stuck. Pending operations are queued resizes that have not yet been executed. Castellum processes these asynchronously. Only flag operations that have been pending for an unusually long time (hours).
Failed operations include the failure reason. The
recently-failedendpoint shows why a resize failed (e.g., parent quota exhausted, constraint violation). This is the primary diagnostic tool for scaling failures.Not all resources are auto-scalable. Only resources that have Castellum configuration will appear. If
get_project_resourcesreturns empty or missing resources, those resources are not configured for autoscaling.Thresholds define when scaling triggers. Each configured resource has usage thresholds (high/low) that trigger upscale/downscale. The
get_project_resourcesresponse shows these thresholds alongside current usage.
Common Workflows
Check Autoscaling Configuration for a Project
castellum_get_project_resourceswithproject_id=<uuid>— see all configured resources and their thresholds.- For each resource, note the high/low thresholds and current usage percentage.
- Cross-reference with
limes_get_project_quotato see actual quota values.
Diagnose Why a Resource Did Not Autoscale
castellum_list_recently_failed_operationswithproject_id=<uuid>— check for failures.- If failures exist, read the error reason (typically quota exhaustion at parent level).
- If no failures and no pending ops,
castellum_get_project_resources— check if thresholds are configured and if usage is actually above the high threshold.
Monitor Pending Resize Operations
castellum_list_pending_operations— see all queued resizes (optionally filter by project or asset_type).- Check timestamps — operations pending for over an hour may indicate a processing backlog.
- If a specific resource is pending, verify the parent quota has headroom via Limes.
Cross-Service References
| Need | Service | Tool |
|---|---|---|
| Current quota and usage values | Limes | limes_get_project_quota |
| Project UUID from name | Keystone | keystone_list_projects |
| Audit trail of resize actions | Hermes | hermes_list_events(initiator_name=castellum) |
| Compute resource details | Nova | nova_list_servers |