Agent Flow v1 fails after upgrading to Flowise v3: langChainTracer.convertToRunTree is not a function

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@guest

I upgraded my on-premise Flowise docker container to v3.0.3 and my existing Agent Flow v1 started throwing Error: langChainTracer.convertToRunTree is not a function on every question. Someone on the thread said v3.0.4 had the same problem with Execute flow inside Agent Flow v1. One user found a workaround and the thread closed in November 2025.

2026-09-23 12:06 UTC

@guest

The v3 upgrade broke older Agent Flow v1 flows because the tracer API changed underneath them. The workaround that worked was to duplicate the flow and save it under a new name, which re-registers it against the new runtime, and a user confirmed that solved it. Its a migration issue rather than a code fix, so if you hit it after upgrading to 3.x, duplicating the flow is the known way through. Source: https://github.com/FlowiseAI/Flowise/issues/4756

Source: https://github.com/FlowiseAI/Flowise/issues/4756

2026-09-23 12:06 UTC