Flow execution stops at Condition node when multiple branches converge into single LLM node

[Sohorev]

Describe the bug

Flow execution stops at a Condition node without proceeding to any branch when multiple edges converge into a single LLM node. The flow terminates silently without error.

To Reproduce

1. Import attached bug-flow.json into Flowise
2. Start chat and send: hi

Expected behavior

Condition evaluates to false (not empty), takes output 1, executes to_operator

Actual behavior:

• Flow execution stops at the Condition node (flow.stopReason is empty)
• No branch is executed (neither output 0 nor output 1)
• No error is thrown
• Flow terminates silently
• Flow state shows:

  {
    "nextAgent": "",
    "intsructions": "",
    "stopReason": "not_empty"
  }

Workaround

If you duplicate the to_operator LLM node and route different branches to separate (but identical) nodes, the bug disappears. This confirms the issue is related to multiple edges converging into a single node.

Screenshots

Flow

bug-flow.json

Use Method

Docker

Flowise Version

3.0.10

Operating System

Linux

Browser

Firefox

Additional context

bug-flow.json

[Sohorev]

I have no objections if someone fixes this bug; I won't be able to do it myself.

[HenryHengZJ]

why do you have the output of conditions merge into same node? then it wouldn't really make sense to have a condition?

[Domenic-MZS]

why do you have the output of conditions merge into same node? then it wouldn't really make sense to have a condition?

....

@HenryHengZJ I think that is just for simplicity, it's the minimum to show when the bug occurs...

I have a more realistic scenario where, based on an external factor such as a role, the user is given the choice to execute a special function or simply follow the standard flow. The current bug is preventing a potential convergence into the standard flow path, which is where the issue lies.

---

[Domenic-MZS]

Expected output should be something like this:

I'll open a PR with the needed changes