Write-only. Required keys per platform — telegram: bot_token · discord: bot_token · slack: bot_token, signing_secret · whatsapp: access_token, phone_number_id, app_secret · email (requires EMAIL_CHANNEL_ENABLED): region, access_key, secret_key, from_address, sns_topic_arn; optional from_name, inbound_address, allow_subaddressing, reply_to_sender_only (string true/false); optional s3_bucket, s3_prefix (nonempty, ends /), s3_bucket_owner (12 digits), all three together for S3 receiving with the same region/key pair · teams (when enabled; app creation and credential rotation return 501 coming_soon when disabled): app_id (Azure Application client ID), app_password (client secret); optional app_tenant_id (Directory ID for single-tenant bots, omit for multi-tenant). Credentials are validated against Azure AD on creation. The API returns a webhook_url to paste into Azure Bot Configuration → Messaging Endpoint. Connection returns PENDING and a LINK code to send to the bot. Each conversation can bind to its own session. · imessage (coming soon — answers 501 coming_soon today): api_key, phone_number, webhook_secret · x: consumer_secret + either user_access_token (Group A, OAuth 2.0 Bearer) or client_id + refresh_token (Group B, OAuth 2.0 managed refresh). Exactly one group must be supplied. · lark: app_id, app_secret, verification_token (optional encrypt_key, domain: lark|feishu, app_mode: self-built|store, app_ticket for migration) · buzz: private_key, auth_tag · gchat: service_account_json, project_number · line: channel_access_token, channel_secret (requires LINE_CHANNEL_ENABLED; setup returns manual webhook instructions)