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/teams-app-developer

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Builds, tests, and deploys Microsoft 365 apps and agents for Teams and Copilot. Includes sub-skills for project creation, local testing, cloud deployment, troubleshooting, and Slack-to-Teams migration. USE FOR: Teams agent, bot, tab, message extension, Declarative Agents, Custom Engine Agents, local testing, Agents Playground, Azure resource provision, remote deployment, Slack to Teams migration, cross-platform bot development, Block Kit to Adaptive Cards conversion. DO NOT USE FOR: general web development, non-bot/non-Teams projects.

Use this Skill: https://skilld.dev/gh/microsoft/skills/teams-app-developer

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toolkitenvironments.md

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Environments and .localConfigs

purpose

Multi-environment management with environment files, ${{VAR}} variable resolution, the SECRET_ prefix convention, and the .localConfigs runtime-config flow for Agents Toolkit projects.

rules

  1. Environment files live in env/. Each environment has a pair of files: env/.env.{name} for shared config and env/.env.{name}.user for personal/secret values. The environmentFolderPath in m365agents.yml points to this folder.
  2. Default environment is dev. Scaffolded projects create env/.env.dev and env/.env.dev.user. Additional environments (staging, production) are created by running atk provision --env <name>.
  3. Variable syntax is ${{VAR_NAME}}. Both manifest.json and m365agents.yml use ${{VAR_NAME}} placeholders. At build/provision/deploy time, the toolkit resolves them from the active environment's .env files.
  4. SECRET_ prefix marks sensitive values. Variables prefixed with SECRET_ (e.g., SECRET_BOT_PASSWORD, SECRET_AAD_APP_CLIENT_SECRET) are stored only in .env.*.user files, which are gitignored. Never put SECRET_ values in .env.{name}.
  5. .env.*.user files are gitignored by default. The scaffold includes a .gitignore entry for env/.env.*.user. These files contain developer-specific credentials and secrets. Never commit them.
  6. Built-in environment variables are auto-populated. Lifecycle actions write outputs to env files via writeToEnvironmentFile. Common auto-populated vars: TEAMS_APP_ID, BOT_ID, SECRET_BOT_PASSWORD, AAD_APP_CLIENT_ID, SECRET_AAD_APP_CLIENT_SECRET, AAD_APP_OBJECT_ID, AAD_APP_TENANT_ID.
  7. Azure resource variables must be set per environment. AZURE_SUBSCRIPTION_ID and AZURE_RESOURCE_GROUP_NAME are required for provisioning. Set them in .env.{name} or pass via CLI/CI environment.
  8. Custom environments mirror the dev structure. To create a staging environment, run atk provision --env staging. This creates env/.env.staging and env/.env.staging.user with the same variable structure as dev but pointing to separate cloud resources.
  9. VS Code sidebar switches environments. The Agents Toolkit VS Code extension shows a dropdown in the sidebar to switch the active environment. This changes which .env.{name} files are used for provision, deploy, and preview commands.
  10. Manifest placeholders resolve at package time. When atk package or teamsApp/zipAppPackage runs, all ${{VAR}} placeholders in manifest.json are replaced with values from the active environment. The output zip contains a fully resolved manifest.
  11. Environment-specific resource isolation. Each environment should use separate Azure resource groups to avoid resource conflicts. Use naming conventions like rg-mybot-dev, rg-mybot-staging, rg-mybot-prod.
  12. .localConfigs is the runtime config for local development. atk deploy --env local generates .localConfigs by reading values from env/.env.local and transforming them via file/createOrUpdateEnvironmentFile in m365agents.local.yml. Your app reads .localConfigs at runtime — NOT env/.env.local. If TENANT_ID is missing from .localConfigs, copy the tenant value from the source variable in env/.env.local (for example, TEAMS_APP_TENANT_ID) into TENANT_ID, or update the local lifecycle mapping so it writes TENANT_ID into .localConfigs.

patterns

Pattern 1: Environment file structure

project-root/
├── m365agents.yml
├── env/
│   ├── .env.dev                  # Shared dev config (committed)
│   ├── .env.dev.user             # Dev secrets (gitignored)
│   ├── .env.staging              # Shared staging config (committed)
│   ├── .env.staging.user         # Staging secrets (gitignored)
│   ├── .env.production           # Shared production config (committed)
│   └── .env.production.user      # Production secrets (gitignored)
└── appPackage/
    └── manifest.json             # Uses ${{VAR}} placeholders
# env/.env.dev — shared config (safe to commit)
APP_ENV=dev
TEAMS_APP_NAME=MyBot-Dev
TEAMS_APP_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
BOT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
BOT_DOMAIN=mybot-dev.azurewebsites.net
BOT_ENDPOINT=https://mybot-dev.azurewebsites.net/api/messages
AZURE_SUBSCRIPTION_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
AZURE_RESOURCE_GROUP_NAME=rg-mybot-dev
AAD_APP_CLIENT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
AAD_APP_OBJECT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
AAD_APP_TENANT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
# env/.env.dev.user — secrets (gitignored)
SECRET_BOT_PASSWORD=your-bot-password-here
SECRET_AAD_APP_CLIENT_SECRET=your-client-secret-here

Pattern 2: Variable resolution in manifest.json

// appPackage/manifest.json — placeholders resolve from active env
{
  "$schema": "https://developer.microsoft.com/en-us/json-schemas/teams/v1.26/MicrosoftTeams.schema.json",
  "manifestVersion": "1.26",
  "version": "1.0.0",
  "id": "${{TEAMS_APP_ID}}",
  "name": {
    "short": "${{TEAMS_APP_NAME}}",
    "full": "${{TEAMS_APP_NAME}} - Full"
  },
  "bots": [
    {
      "botId": "${{BOT_ID}}",
      "scopes": ["personal", "team", "groupChat"]
    }
  ],
  "validDomains": [
    "${{BOT_DOMAIN}}"
  ]
}

Pattern 3: Creating and provisioning a new environment

# Step 1: Provision creates the env files and cloud resources
atk provision --env staging -i false

# This creates:
#   env/.env.staging          (with APP_ENV=staging, resource IDs)
#   env/.env.staging.user     (with SECRET_* values)

# Step 2: Set environment-specific overrides
# Edit env/.env.staging to adjust resource names, domains, etc.

# Step 3: Deploy to the new environment
atk deploy --env staging -i false

# Step 4: Test against the new environment
# Use agentsplayground CLI or sideload in Teams

Pattern 4: Cross-Platform Environment Variables

Cross-platform bots (Teams + Slack) keep both platforms' credentials in a single .env file at the project root. Toolkit ${{VAR}} placeholders live only in appPackage/manifest.json — they are not the same as runtime process.env vars consumed by Slack or Express.

# .env — cross-platform bot (single file, project root)

# Teams credentials (used at runtime by @microsoft/teams.apps)
CLIENT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
CLIENT_SECRET=your-client-secret
TENANT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

# Agents Toolkit vars (used in appPackage/manifest.json ${{VAR}} placeholders)
BOT_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
BOT_DOMAIN=mybot.azurewebsites.net
TEAMS_APP_ID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

# Slack credentials (used at runtime by @slack/bolt)
SLACK_BOT_TOKEN=xoxb-your-slack-bot-token
SLACK_APP_TOKEN=xapp-your-slack-app-token
SLACK_SIGNING_SECRET=your-slack-signing-secret

# Server
PORT=3978

Key difference from Toolkit-managed projects: Standalone cross-platform examples use a single .env file (loaded via dotenv) instead of the env/.env.dev + env/.env.dev.user pair. This is intentional — these examples don't ship m365agents.yml or run atk provision.

Key Environment Variables

Variable Where Set Purpose
BOT_ID env/.env.local (by atk provision) Azure AD app client ID
SECRET_BOT_PASSWORD env/.env.local.user (by atk provision) Azure AD app client secret
TEAMS_APP_ID env/.env.local (by atk provision) Teams app ID for sideloading
M365_APP_ID env/.env.local (by teamsApp/extendToM365) M365 app ID for declarative agents
TEAMS_APP_TENANT_ID env/.env.local (by atk provision) Tenant ID
BOT_ENDPOINT env/.env.local (manual — set to devtunnel URL) Bot HTTPS endpoint for Teams
AZURE_SUBSCRIPTION_ID env/.env.dev (manual) Azure subscription for cloud deploy
AZURE_RESOURCE_GROUP_NAME env/.env.dev (manual or by --resource-group) Azure resource group for cloud deploy
SECRET_AZURE_OPENAI_API_KEY env/.env.local.user (manual) Azure OpenAI API key
AZURE_OPENAI_ENDPOINT env/.env.local (manual) Azure OpenAI endpoint URL
AZURE_OPENAI_DEPLOYMENT_NAME env/.env.local (manual) Azure OpenAI deployment name

.localConfigs runtime config flow (local development)

For local and playground environments, m365agents.local.yml uses file/createOrUpdateEnvironmentFile to write env vars to .localConfigs (not env/.env.local).

# Example from m365agents.local.yml
- uses: file/createOrUpdateEnvironmentFile
  with:
    target: ./.localConfigs
    envs:
      PORT: 3978
      CLIENT_ID: ${{BOT_ID}}
      CLIENT_SECRET: ${{SECRET_BOT_PASSWORD}}
      TENANT_ID: ${{TEAMS_APP_TENANT_ID}}

Configuration flow:

  • env/.env.local → source of truth (edited manually or by atk provision)
  • m365agents.local.yml → defines how to transform env vars
  • .localConfigs → generated file your app reads at runtime (created by atk deploy --env local)

Missing environment variables at runtime

  1. Check .localConfigs exists and has the required values
  2. Ensure values are set in env/.env.local (or env/.env.local.user for secrets)
  3. Ensure m365agents.local.yml maps those values to .localConfigs
  4. Run atk deploy --env local -i false to regenerate .localConfigs

pitfalls

  • Committing .env.*.user files — These contain SECRET_* values. Verify .gitignore includes env/.env.*.user before any commit.
  • Putting secrets in .env.{name} instead of .env.{name}.user — Non-user env files are committed. Always use the SECRET_ prefix and store in .user files.
  • Forgetting to set AZURE_SUBSCRIPTION_ID for new environments — Provisioning fails silently or targets the wrong subscription without this variable.
  • Reusing resource groups across environments — Dev and staging sharing a resource group causes resource name conflicts and accidental overwrites during provisioning.
  • Stale env files after re-provisioning — If you delete cloud resources and re-provision, old IDs in env files may not update. Delete the env files and re-provision from scratch.
  • ${{VAR}} vs ${VAR} confusion — Agents Toolkit uses double-brace ${{VAR}}. Shell-style ${VAR} is not recognized and will not resolve.
  • Confusing Toolkit ${{VAR}} placeholders with Slack runtime env vars — Toolkit placeholders resolve at package/provision time in manifest files. Slack env vars (SLACK_BOT_TOKEN, SLACK_APP_TOKEN) are read at runtime by @slack/bolt. They live in different worlds — don't put Slack tokens inside ${{}} brackets in the manifest.
  • Missing variables at package time — If a ${{VAR}} in manifest.json has no matching env entry, packaging fails. Run atk validate first to catch these.
  • CI/CD without .user files — In CI, secrets come from pipeline secrets, not .user files. Set SECRET_* vars as environment variables in the CI runner.

references

instructions

Do a web search for:

  • "Microsoft 365 Agents Toolkit multi-environment env files configuration 2025"
  • "atk provision --env staging multiple environments"
  • "Agents Toolkit SECRET_ prefix environment variables"

Pair with:

  • lifecycle-cli.md — lifecycle hooks that consume environment variables
  • ../experts/teams/runtime.manifest-ts.md — manifest ${{VAR}} placeholder resolution
  • ../experts/teams/project.scaffold-files-ts.md — scaffolded project includes env/ directory
  • publish.md — publishing requires fully resolved environment variables

research

Deep Research prompt:

"Write a micro expert on Microsoft 365 Agents Toolkit environment management (TypeScript). Cover env/.env.{name} and env/.env.{name}.user file pairs, ${{VAR}} variable resolution in manifest.json and m365agents.yml, SECRET_ prefix convention, built-in environment variables (TEAMS_APP_ID, BOT_ID, BOT_PASSWORD, AZURE_SUBSCRIPTION_ID), creating custom environments with atk provision --env, VS Code sidebar environment switching, and CI/CD environment variable injection. Include canonical patterns for: environment file structure, manifest placeholder resolution, multi-environment setup."

Source: SKILL.md on GitHub

1 alert3mo3 checks · Risk SAFE
  • Gen Agent Trust Hub3mo

    This skill provides a comprehensive developer guide for building Microsoft 365 agents and Teams applications. It includes several security considerations such as handling untrusted user input, using dynamic execution in examples, and reading sensitive local files for protocol requirements. These patterns are presented with appropriate security warnings and architectural mitigations. See detailed analysis for more context.

  • Socket3mo

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  • Snyk3mo

    Risk: HIGH · 1 issue

Signed by skilld at 0bef15b. This ties the file your Agent reads to that commit on GitHub. It does not review the instructions.

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Activeupdated 3 months ago

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