The layer model

Data leaves the plant's own systems through connectors into one context store in L2. Analytics in L3 detects, estimates and predicts, and a method router picks what the evidence supports or abstains. The decision layer in L4 turns that into at most one Prescription per condition, and every proposal passes the predictive safety filter. L5 makes it a card for a person on shift, and later, where a plant grants it, a confirmed write. Outcomes land in the value ledger, which feeds learning back into L3 and L4.

Layer model

⑥ Layer 6 · Value

⑤ Layer 5 · Action

③ Layer 3 · Analytics (seven-job chain, jobs 1–5)

② Layer 2 · Context

① Layer 1 · Plant systems (customer-owned)

proposes to the router

context, states, metrics

chosen method, or abstain

proposals

approved only

outcomes

reads layers 2 to 4

④ Layer 4 · Decision (jobs 6–7)

Prescriptions ranked by value and confidence

Optimisation: set-point, scheduling, tariff

Control: rule → advice → BO/EVOP
Later: MPC; shielded RL not in the next 12 months

Governance plane (applies to every layer; no arrows drawn)
• Data quality, evidence labels, calibration gates
• Model registry, evals, sustainment (re-ID, model health)
• Autonomy policy
• Message/alarm budgets and disposition
• Audit trail, intervention log, episode_id
• Predictive safety filter (drawn in the flow below)

PLC, DCS, SIS, historians, meters, MES, ERP, paper

Connectors and fast read, one ingest path

Context store in L2: assets, topology, states, lots, genealogy links with confidence, documents

Semantic metric layer

SPC → MSPC → residuals

Estimation (KF family, twins)

Prediction: soft sensors, forecasts

Causal quality and attribution

Method-selection router with abstain

Predictive safety filter (governance plane): every proposal passes here

Messages and cards

Experiments: step tests, EVOP, switchback

Policy-granted write-back

Operator feedback and overrides

Value ledger: counterfactual M&V per KPI

↩ Back to Layer 1: approved writes only, inside the plant's limits

↩ Learning and sustainment: the ledger updates layers 3 and 4 and the model registry, with review

Agents: read-only tools over layers 2 to 4, propose only

Read the layer model chapter

Latest changes

Full changelog
  • v1.0.02026-10-07

    Initial version. This is the first versioned architecture.

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