/azure-functions

name: azure-functions
description: Expert knowledge for Azure Functions development including troubleshooting, best practices, decision making, limits & quotas, security, configuration, integrations & coding patterns, and deployment. Use when building trigger/binding workflows, VNet/managed identity access, CI/CD deployments, monitoring, or scaling, and other Azure Functions related development tasks. Not for Azure App Service (use azure-app-service), Azure Container Apps (use azure-container-apps), Azure Logic Apps (use azure-logic-apps), Azure Kubernetes Service (AKS) (use azure-kubernetes-service).
compatibility: Requires network access. Uses mcp_microsoftdocs:microsoft_docs_fetch or fetch_webpage to retrieve documentation.
metadata:
  generated_at: "2026-11-08"
  generator: "docs2skills/1.0.0"

Azure Functions Skill

This skill provides expert guidance for Azure Functions. Covers troubleshooting, best practices, decision making, limits & quotas, security, configuration, integrations & coding patterns, and deployment. It combines local quick-reference content with remote documentation fetching capabilities.

How to Use This Skill

> **IMPORTANT for Agent**: Use the **Category Index** below to locate relevant sections. For categories with line ranges (e.g., `L35-L120`), use `read_file` with the specified lines. For categories with file links (e.g., `[security.md](security.md)`), use `read_file` on the linked reference file

> **IMPORTANT for Agent**: If `metadata.generated_at` is more than 3 months old, suggest the user pull the latest version from the repository. If `mcp_microsoftdocs` tools are not available, suggest the user install it: [Installation Guide](https://github.com/MicrosoftDocs/mcp/blob/main/README.md)

This skill requires **network access** to fetch documentation content:

• **Preferred**: Use `mcp_microsoftdocs:microsoft_docs_fetch` with query string `from=learn-agent-skill`. Returns Markdown.
• **Fallback**: Use `fetch_webpage` with query string `from=learn-agent-skill&accept=text/markdown`. Returns Markdown.

Category Index

| Category | Lines | Description | |----------|-------|-------------| | Troubleshooting | L36-L73 | Diagnosing and fixing Azure Functions errors and warnings (AZFD/AZFW codes), including storage/config issues, runtime/version problems, networking, Core Tools, and language-specific (Node.js/Python) troubleshooting. | | Best Practices | L74-L91 | Best practices for performance, reliability, idempotency, DI, HttpClient, event processing, and memory/throughput optimization in .NET, Node.js, and Python Azure Functions | | Decision Making | L92-L115 | Guidance on choosing Functions hosting/scale/networking options, cost planning, AI integration, and step-by-step migrations (plans, runtimes, languages, extensions, AWS Lambda). | | Limits & Quotas | L116-L122 | Scaling limits, concurrency settings, target-based trigger scaling, and language/runtime support lifecycles for Azure Functions. | | Security | L123-L135 | Guides for securing Functions: encryption at rest, secure storage and keys, private access (VNet/private endpoints), managed identity for SQL, and App Service security features. | | Configuration | L136-L182 | Configuring Azure Functions behavior, bindings, triggers, networking, runtime versions, monitoring (App Insights/OpenTelemetry), local dev tools, and specialized hosted skills/workflows. | | Integrations & Coding Patterns | L183-L287 | Patterns and examples for wiring Functions to external systems (bindings, triggers, outputs), including Azure services, Dapr, MCP, OpenAI, messaging, storage, and language-specific integration code. | | Deployment | L288-L316 | Deploying and hosting Azure Functions: provisioning plans, CI/CD (GitHub/Azure Pipelines), slots, containers/Kubernetes, Flex migrations, language-specific deploy guides, and rollback/recovery. |

Troubleshooting

| Topic | URL | |-------|-----| | Resolve AZFD0001 missing AzureWebJobsStorage setting | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0001 | | Fix AZFD0002 invalid AzureWebJobsStorage value | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0002 | | Troubleshoot AZFD0003 StorageException fetching diagnostics | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0003 | | Resolve AZFD0004 Azure Functions host ID collision | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0004 | | Fix AZFD0005 external startup exception in Functions | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0005 | | Resolve AZFD0006 SAS token expiring in Functions | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0006 | | Resolve AZFD0007 too many secrets backups | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0007 | | Fix AZFD0008 archive-tier Blob secrets repository | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0008 | | Resolve AZFD0009 unable to parse host.json | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0009 | | Fix AZFD0010 TZ/WEBSITE_TIME_ZONE on Linux Consumption | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0010 | | Resolve AZFD0011 missing FUNCTIONS_WORKER_RUNTIME | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0011 | | Fix AZFD0013 mismatched FUNCTIONS_WORKER_RUNTIME and payload | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0013 | | Resolve AZFD0015 non-CRON timer trigger schedule | https://learn.microsoft.com/en-us/azure/azure-functions/errors-diagnostics/diagnostic-events/azfd0