Actor Assignment — Human-in-the-Loop

Assignment Methods

Method	Configuration	Use When
Static User	`"actorId": "user-abc123"`	Always the same person — e.g., a department head
Static Group	`"actorId": "group-finance", "actorType": "Group"`	Any member of the finance team can handle it
Dynamic Expression	`"actorId": "$output.getManagerNode.managerId"`	Manager must be fetched from HR system at runtime
Trigger Actor	`"actorId": "$context.actorId"`	Send the task back to whoever triggered the workflow
AI Agent (Octopus)	`"actorType": "Agent", "actorId": "octopus-agent-1"`	An AI agent handles the task autonomously

Dynamic Expression Examples

// Get manager from upstream HTTP node
"actorId": "$output.fetchManagerNode.data.managerId"

// Use workflow variable set by a previous node
"actorId": "$var.assignedReviewer"

// Conditional assignment using ternary
"actorId": "$output.routeNode.department === 'Finance'
           ? 'user-finance-head'
           : 'user-operations-head'"

Group Assignment Behaviour

When a group is assigned, all current members of the group receive a notification and can see the task in their inbox. The first group member to respond completes the task. Subsequent responses from other members are rejected with a "task already completed" message.

// Group assignment in node config
{
  "actorId"  : "group-contract-reviewers",
  "actorType": "Group"
}

AI Agent Assignment

When an Octopus AI agent is the actor, the HIL task is delivered to the agent's task queue. The agent processes the task using its configured tools and memory, then calls the resume API with its decision or form submission. From the engine's perspective, this is identical to a human response — the actor is simply automated.

Dynamic expression failure: If a dynamic expression fails to resolve (e.g., the referenced node has not run yet, or the field is null), the HIL node throws an ActorResolutionException and the workflow fails. Test dynamic actor expressions with diverse execution paths.

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