Triggers, Entries & Payloads

Triggers and Entries both start execution chains, but they model different ownership. Use a Trigger when Flow Core listens for an event. Use an Entry when another caller explicitly requests a named graph behavior.

Trigger

A Trigger is an event-based start point. Trigger sources include Unity lifecycle, UI, input, Blackboard changes, signals, and module-specific events.

Examples:

• Unity Start begins initialization behavior.
• A UI button click begins a confirmation sequence.
• A Blackboard value change begins a reaction.
• A Stats or Character event begins module-specific logic.

The Trigger may supply a payload describing the event. The available payload depends on the selected Trigger.

Entry

An Entry is a named graph start point, represented by an Enter node. Code, another graph path, or a supported runtime integration can execute it by identity or title.

Use an Entry when the caller already owns timing: a quest system requests QuestAccepted, a test calls RunValidation, or gameplay code calls SayHello.

Do not expect an Entry API to activate a Trigger. They are distinct start models.

此处插图应该是同一 Flow Graph 中 Trigger 与 Enter 节点并排的截图；Trigger 标注为 Event-owned start，Enter 标注为 Caller-owned start，并显示两者各自连接到 Action。

payload ownership

payload is data supplied when the chain starts. It belongs to that active chain and should be read as event context, not treated as a general storage location.

Typical payload data includes:

• the object that raised an event;
• a UI or input value;
• an interaction target;
• a module event snapshot;
• a caller-supplied value.

If later chains need the value, write the required typed result to an intentionally owned Blackboard key. If only later Instructions in the same chain need a derived value, use TempPayload.

Decision guide

Situation	Start with	Data source
Unity lifecycle owns timing	Trigger	Trigger payload or Blackboard
UI or input event owns timing	Trigger	Event payload
Gameplay code owns timing	Entry	Caller context or Blackboard
Several listeners need a decoupled signal	Event Trigger	Published signal payload
A previous step computed temporary data	Existing chain	TempPayload

Common misunderstandings

• A Trigger is not an Entry with a different icon.
• Renaming an Entry can break callers that use its title.
• A payload does not persist after the chain as shared state.
• Subgraph Triggers receive events only while their activation window is active; lifecycle events are not replayed later.

Related

• Running Graphs from C#
• Blackboard & Typed Values
• Nodes, Ports & Execution Chains