Teams App Developer Skill

Build code-based Microsoft 365 agents and Teams apps (CEA, bot, tab, message extension) using the ATK CLI.

Declarative Agents (DA): Use the declarative-agent-developer skill — it owns all DA workflows including scaffolding, manifest editing, capability config, API/MCP plugins, OAuth, localization, and deployment. This skill covers code-based project types only.

AI Behavior Guidelines

1. Testing Strategy: Recommend Agents Playground first (faster, no M365 needed). Use Teams workflow only if user explicitly requests it.

2. Environment Variables: NEVER hardcode secrets or make up placeholder values. Always ask users for real values.

3. Error Handling: Read error messages carefully. Check env/.env.local, .localConfigs, and atk auth list. Common pitfalls:

   • AADSTS7000229 → aadApp/create missing generateServicePrincipal: true in YAML — add it and re-provision
   • Missing TENANT_ID in .localConfigs → SDK uses wrong token authority → 401 from Bot Connector
   • 401 persists after auth fix → devtunnel URL may be blacklisted — create a fresh tunnel
   • See troubleshoot/troubleshoot.md for full diagnostic steps