Debug Azure production issues on Azure using AppLens, Azure Monitor, resource health, and safe triage. WHEN: debug production issues, troubleshoot app service, app service high CPU, app service deployment failure, troubleshoot container apps, troubleshoot functions, troubleshoot AKS, VM RDP, Linux S

Azure Diagnostics AUTHORITATIVE GUIDANCE — MANDATORY COMPLIANCE This document is the official source for debugging and troubleshooting Azure production issues. Follow these instructions to diagnose and resolve common Azure service problems systematically. Triggers Activate this skill when user wants to: Debug or troubleshoot production issues Diagnose errors in Azure services Analyze application logs or metrics Fix image pull, cold start, or health probe issues Investigate why Azure resources are failing Find root cause of application errors Troubleshoot App Service issues (high CPU, deployment failures, crashes, slow responses, TLS/custom domains) Respond to prompts like "troubleshoot app service", "app service high CPU", or "app service deployment failure" Troubleshoot Azure Function Apps (invocation failures, timeouts, binding errors) Find the App Insights or Log Analytics workspace linked to a Function App Troubleshoot AKS clusters, nodes, pods, ingress, or Kubernetes networking issues Troubleshoot Azure VM connectivity issues (RDP/SSH failures, port 3389/22 timeouts, NSG or firewall blocking, credential resets) Troubleshoot Azure Messaging SDK issues (Event Hubs, Service Bus connection failures, AMQP errors, message lock issues) Root cause a symptom that looks like a healthy runtime but wrong destination problem (e.g., telemetry/messages stop flowing to the expected resource after a config change) — invoke this skill for the matrix even when MCP tools could answer the surface question alone Rules 1. Start with systematic diagnosis flow 2. Use supplied evidence first. If the user requests evidence only analysis or prohibits live Azure access, do not query or modify Azure. Diagnose from the supplied logs, metrics, and timeline; identify assumptions and provide optional verification steps. 3. Use AppLens (MCP) for AI powered diagnostics when available 4. Check resource health before deep diving into logs 5. Select appropriate troubleshooting guide based on service type 6. Document findings and attempted remediation steps 7. Prefer bundled diagnostic scripts over ad hoc calls for permitted live collection when identifiers are known. If supplied evidence suffices or live access is prohibited, don't run them; otherwise run the applicable script first. 8. Route AKS incidents to the dedicated AKS troubleshooting document 9. Keep baseline AKS diagnostics available even when the optional aks skills add on is absent, declined, or unsupported by the host Quick Diagnosis Flow 1. Identify symptoms What's failing? 2. Check resource health Is Azure healthy? 3. Review logs What do logs show? 4. Analyze metrics Performance patterns? 5. Investigate recent changes What changed? Troubleshooting Guides by Service Service Common Issues Reference Container Apps Image pull failures, cold starts, health probes, port mismatches [container apps/](references/container apps/README.md) App Service High CPU, deployment failures, crashes, slow responses, TLS/custom domains [app service/](references/app service/README.md) Function Apps App details, invocation failures, timeouts, binding errors, cold starts, missing app settings [functions/](references/functions/README.md) AKS Cluster access, nodes, kube system , scheduling, crash loops, ingress, DNS, upgrades [AKS Troubleshooting](troubleshooting/aks/aks troubleshooting.md) Compute VM RDP/SSH connectivity, NSG/firewall blocks, credential resets, VM agent/tooling issues [VM Connectivity Troubleshooting](troubleshooting/compute/vm troubleshooting.md) Messaging Event Hubs & Service Bus SDK errors, AMQP failures, message lock, connectivity [Messaging Troubleshooting](troubleshooting/messaging/README.md) Routing Keep Container Apps and Function Apps diagnostics in this parent skill. Route active AKS incidents, AKS specific intake, evidence gathering, and remediation guidance to [AKS Troubleshooting](troubleshooting/aks/aks troubleshooting.md). Route Azure VM RDP/SSH connectivity, NSG/firewall, credential reset, and VM agent troubleshooting to [VM Connectivity Troubleshooting](troubleshooting/compute/vm troubleshooting.md). Route Azure Messaging SDK troubleshooting (Event Hubs, Service Bus) to [Messaging Troubleshooting](troubleshooting/messaging/README.md). Quick Reference Common Diagnostic Commands AppLens (MCP Tools) For AI powered diagnostics, use: Azure Monitor (MCP Tools) For querying logs and metrics: See [kql queries.md](references/kql queries.md) for common diagnostic queries. Check Azure Resource Health Using MCP Using CLI References [KQL Query Library](references/kql queries.md) [Azure Resource Graph Queries](references/azure resource graph.md) [App Service Troubleshooting](references/app service/README.md) [Function Apps Troubleshooting](references/functions/README.md) [VM Connectivity Troubleshooting](troubleshooting/compute/vm troubleshooting.md) [Messaging Troubleshooting](troubleshooting/messaging/README.md)

azure-diagnostics