ANSWER HUB

RunLedger for langgraph

RunLedger can drive LangGraph flows as long as tool nodes emit tool_call and wait for tool_result.

integration langgraph tools Updated 2026-01-26

Direct Answer

Run your LangGraph agent under RunLedger and route tool nodes through tool_call/tool_result so replay can provide deterministic fixtures.

Quick Decision

Use RunLedger when Consider alternatives when
You can adapt tool nodes to the protocol. You cannot modify the graph execution.
You need deterministic replay in CI. You only need manual evaluation.
You want PR gating on regressions. You only need qualitative scores.

Integration outline

  • Read task_start input to seed the graph.
  • Wrap tool nodes to emit tool_call events.
  • Use tool_result to resume the graph execution.

Protocol reminder

Note RunLedger provides tool results in replay mode, so tools should not call live services in CI.

Tradeoffs

  • Requires adapter logic in tool nodes.
  • Strict tool ordering may need graph constraints.
  • Replay can drift from live behavior if tools change.

When NOT to use RunLedger

Avoid if your LangGraph runtime cannot be wrapped to emit protocol events.

Next steps