id: dify-agent-debug-chat
title: "Dify AgentRunner returns a response through Pipeline Debug Chat"
mode: agent-browser
area: pipeline
type: provider
priority: p2
risk: medium
ci_eligible: false
tags:
  - dify
  - agent-runner
  - pipeline
skills:
  - langbot-env-setup
  - langbot-testing
env:
  - LANGBOT_FRONTEND_URL
  - LANGBOT_BACKEND_URL
preconditions:
  - "A Dify app Service API key is available from the active secret source and must not be printed in reports."
  - "The target pipeline is safe to modify for Dify runner configuration."
steps:
  - "Ensure a Dify app Service API key is available from the active secret source."
  - "Open LANGBOT_FRONTEND_URL."
  - "Navigate to Pipelines and open the target pipeline."
  - "Open Configuration > AI."
  - "Select runner Dify."
  - "Set Base URL, App Type, API Key, Base Prompt, and Timeout according to references/dify-agent-runner.md."
  - "Save the pipeline."
  - "Open Debug Chat."
  - "Send a prompt asking the bot to reply exactly with a unique sentinel, for example LANGBOT_DIFY_OK_<date>."
checks:
  - "UI: The runner selector and runner config identify Dify, not a generic Default label."
  - "UI: Debug Chat shows a Bot message containing the sentinel."
  - "History/log validation: The sentinel is present in an assistant/bot message, not only in the echoed User message."
  - "Logs: Backend logs show Dify /chat-messages returned HTTP 200 and Conversation(0) Streaming completed."
  - "Console: No unexpected frontend errors appear during runner configuration or Debug Chat."
  - "Secret safety: No Dify API key, JWT, or browser token is printed in reports."
evidence_required:
  - ui
  - console
  - backend_log
diagnostics:
  - "Use direct Dify streaming API only to distinguish invalid Dify credentials from LangBot runner failures."
  - "If direct Dify blocking mode fails for an Agent Chat app, retry streaming before treating credentials as invalid."
  - "Use GET /api/v1/pipelines/{uuid} only to confirm saved runner_config."
troubleshooting:
  - agent-runner-actor-context-fields
  - ambiguous-runner-default-label
  - plugin-runtime-timeout
  - proxy-env-mismatch