Understand FastGPT Workflow Core Execution Rules

Core Workflow Execution Fundamentals

FastGPT Workflows initiate exclusively from the [Workflow Start] node, which triggers automatically when a user submits a question. There is no fixed exit point for workflows: a workflow completes either when all active nodes cease execution, or when no nodes run during a given operational cycle.

Node Connections and Line States

Nodes in FastGPT Workflows have two types of connections: incoming predecessor lines and outgoing successor lines. For example, the [Dataset search] node has one left-side predecessor line and one right-side successor line, while the [AI Chat] node only has a left-side predecessor line. All workflow lines support three defined states:

Node Execution Rules and Walkthrough

The formal rules governing node execution are:

1. If any predecessor line has waiting status, the node remains in a waiting state.
2. If any predecessor line has active status, the node will execute its configured logic.
3. If no predecessor lines are marked waiting or active, the node is skipped entirely.
4. After a node finishes executing, its successor lines are updated to either active or skip status, and all of its predecessor lines are reset to waiting in preparation for future cycles.

A standard execution walkthrough for the sample workflow proceeds as:

1. The [Workflow Start] node completes execution and sets its successor line to active status.
2. The [Dataset search] node detects its single predecessor line is active, executes its configured logic, then updates its successor line to active and resets its predecessor line to waiting.
3. The [AI Chat] node detects its predecessor line is active and executes, at which point the workflow concludes.

Source: FastGPT official source

Applicability and version scope

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Safety guardrails

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Rollback guidance

Restore the prior technical-content authority snapshot. Restore saved configuration and data snapshots, then repeat the smallest verification scenario.