debugging-agents

Debugging Agents

Overview

Systematic diagnosis for Agent2 agent problems. Most issues are config, imports, or missing infrastructure — not code bugs.

When to Activate

• Agent returns 500 errors or problem+json responses
• Agent returns mock data when you expect real LLM output
• Agent Docker container won't start or isn't healthy
• Agent doesn't find knowledge collections
• Agent output doesn't match expected schema
• Tests pass but Docker agent fails

Diagnostic Flowchart

Agent not working?
  ├─ Returns mock data? → Check OPENROUTER_API_KEY (is it set? valid?)
  ├─ 500 error? → Check logs: docker compose logs <agent-name>
  ├─ Container unhealthy? → Check Dockerfile (config copy? PYTHONPATH?)
  ├─ 401/403? → Check API_BEARER_TOKEN matches between client and .env
  ├─ Knowledge search empty? → Is R2R running? (--profile full) Were docs ingested?
  ├─ Schema validation error? → Agent output doesn't match output_type. Check prompt.
  └─ Import error? → Check agent module structure (__init__.py, agent.py naming)

Quick Diagnosis Commands

# 1. Is the container running and healthy?
docker compose ps <agent-name>

# 2. What do the logs say?
docker compose logs <agent-name> --tail=50

# 3. Can you hit the health endpoint?
curl http://localhost:<port>/health

# 4. Does mock mode work? (tests framework without LLM)
curl -X POST http://localhost:<port>/tasks?mode=sync \
  -H "Authorization: Bearer dev-token-change-me" \
  -H "Content-Type: application/json" \
  -d '{"input":{"text":"test"}}'

# 5. Are tests passing?
uv run pytest tests/ -v --tb=short

# 6. Is the Docker Compose config valid?
docker compose config --quiet

Common Issues

Symptom	Cause	Fix
_mock_reason: provider_auth_failed	OPENROUTER_API_KEY is invalid	Get a fresh key from openrouter.ai/keys
Mock data returned, no error	OPENROUTER_API_KEY is empty	Set it in .env
Could not import agent module	Import path wrong in Docker	Check Dockerfile: COPY agents/<name>/ ./agent/ and PYTHONPATH=/app
config.yaml not found	Config not copied in Dockerfile	Add mkdir -p agents/<name> && cp agent/config.yaml agents/<name>/config.yaml
toolsets=None error	Passing None instead of empty list	Use toolsets=[] not toolsets=None
Knowledge search returns nothing	R2R not running or docs not ingested	docker compose --profile full up -d then python -m shared.ingest --all
ProblemError 422	Input shape wrong	input must be a JSON object: {"input": {"text": "..."}}
Container exits immediately	Python import error	Run locally first: uv run python -c "from agents.<name>.agent import agent"
Schema validation retry loop	Agent output doesn't fit Pydantic model	Simplify schema, add clearer prompt instructions, check Field constraints