LangGraph Error Handling

Use This Skill For

• Adding RetryPolicy to flaky nodes (API, DB, model/tool calls)
• Designing LLM recovery loops (Command + error state + retry counters)
• Adding human approval/escalation with interrupt() and resume
• Handling prebuilt ToolNode failures
• Debugging transactional failure behavior in parallel supersteps

Strategy Selection

Use this order:

1. Transient/infrastructure issue (429, timeout, 5xx, temporary DB lock) -> RetryPolicy
2. Recoverable by model/tool args correction -> store error in state and route back with Command
3. Needs user approval or missing info -> interrupt() + resume
4. Unknown/programming bug -> let it bubble up and debug