What is a Loop?

A loop is a governed decision cycle in the runtime taxonomy. This page explains the loop as a product unit; finite states are the mechanism underneath.

The problem

Enterprise AI systems fail when actions are not bounded by explicit state, policy, and traceability.
Loop Engine provides finite states, deterministic transition checks, and event traces that make decisions auditable.

A loop is not a workflow

| | Workflow | Loop | |---|---|---| | Unit of work | Task | Outcome | | State | Implicit | Explicit and named | | Actors | Generic user/system | human / automation / ai-agent / webhook / system | | Failure model | Usually generic step errors | Guard failures and attributed rejections | | Learning | External or absent | Structured signals and measurable outcomes |

Anatomy of a loop (LoopDefinition)

• id: LoopId
• version: string
• description: string
• domain: string
• states: StateSpec[]
• initialState: StateId
• transitions: TransitionSpec[]
• outcome: OutcomeSpec
• participants?: string[]
• spawnableLoops?: LoopId[]
• metadata?: Record<string, unknown>

Use optional fields (participants, spawnableLoops, metadata) only when needed by your platform model.

Lifecycle (LoopStatus)

LoopStatus values: pending | active | completed | failed | cancelled | suspended.

1pending -> active -> completed
2pending -> active -> failed
3pending -> active -> cancelled

User-defined state IDs (like OPEN, PO_CONFIRMED, SETTLED below) are independent of LoopStatus — LoopStatus tracks the lifecycle of the instance itself, while state IDs track position within a specific loop definition.

Real example (abbreviated from loops/scm/procurement.yaml)

1id: scm.procurement
2version: 1.0.0
3domain: scm
4description: Purchase order lifecycle from requisition through settlement
5states:
6  - id: OPEN
7  - id: PO_CONFIRMED
8  - id: RECEIVED
9  - id: INVOICE_MATCHED
10  - id: SETTLED
11    isTerminal: true
12initialState: OPEN
13transitions:
14  - id: confirm_po
15    from: OPEN
16    to: PO_CONFIRMED
17    allowedActors: [human, automation, ai-agent]
18    guards:
19      - id: approval_obtained
20        severity: hard
21        evaluatedBy: external
22        description: PO must be approved before confirmation
23        failureMessage: PO confirmation requires explicit approval
24outcome:
25  id: po_settled
26  description: Purchase order fully settled
27  valueUnit: po_settled
28  measurable: true

Related

• Decision Governance
• When to Use Loop Engine