State model
The source document remains immutable. Derived rules and fragments carry source anchors, compiler version, effective dates and approval state.
Customers and staff may see different wording across terms, notices, help content and historic correspondence, creating uncertainty about which obligation applies.
A knowledge service detects semantic and date conflicts, ranks sources by legal authority and applicability, and assembles a cited explanation or an owned content exception.
Organisations, systems and operating conditions are intentionally anonymised and recomposed. The design demonstrates engineering and banking-domain reasoning; it does not represent a named client estate, vendor product or measured production result.
Typed commands, state changes and receipts cross an event spine without surrendering domain ownership.
Permitted workThe system explains approved information and calculations. Product eligibility, suitability, tax interpretation and legal effect remain separately governed.
Consistency ruleResolve brand, legal entity, product version, jurisdiction and effective date before using a rule or term.
Hard boundaryThe model is not a system of record, identity provider, policy authority or proof that an external effect occurred.
Documents, rules and product content must become effective, attributable and executable without allowing retrieval relevance to decide authority.
The model can identify and explain conflict but cannot choose a customer outcome when source authority or applicability remains disputed.
A deterministic outer workflow contains model-led work inside typed, observable calls. Dashed messages remain proposals until policy or a human grants authority.
The source document remains immutable. Derived rules and fragments carry source anchors, compiler version, effective dates and approval state.
Serving APIs expose rules and evidence separately. Retrieval returns candidates; an authority filter decides whether they may enter context.
A request resolves one effective rule set for its product, jurisdiction and date. Conflicting versions stop consequential conclusions.
These roles are deliberately vendor-neutral. Each can be independently owned, versioned and replaced.
Runs a versioned state machine with explicit waits, deadlines, retries, compensations, human tasks and terminal states.
Appends request, versions, policy result, model proposal, approval, action receipt, readback, correction and custody events under one correlation key.
Chooses an approved model route by task, risk, evidence quality, latency budget and cost ceiling; enforces structured outputs.
Serves owned, audience-qualified and effective-dated content; exposes supersession, withdrawal and dependency metadata.
Evaluates identity, purpose, capability, amount, risk tier and policy version; returns allow, deny, step-up or human-review with reasons.
Durable records carry provenance, authority, effect and custody without turning a transcript into an uncontrolled memory store.
Resolve brand, legal entity, product version, jurisdiction and effective date before using a rule or term.
The selected design is not universally superior. It is the safer fit for this boundary and failure cost.
Keep consequential state transitions deterministic and use models inside bounded steps.
Let the model choose the complete path and recovery sequence.
Cost acceptedThe shell reduces flexibility, but makes deadlines, retries, permissions and recovery testable.
Use append-only events plus a rebuildable current-state projection.
Overwrite the case row with its latest status.
Cost acceptedReplay and storage are more complex, but point-in-time reconstruction and correction lineage remain possible.
Reserve larger models for residual reasoning after deterministic and smaller-model gates.
Send every request to the most capable available model.
Cost acceptedRouting adds evaluation work and operational complexity, but controls cost, latency and unnecessary data exposure.
Federate authoring while centralising lifecycle metadata, validation and serving rules.
Create one centrally authored knowledge corpus.
Cost acceptedFederation requires stronger contracts and owner discipline, but preserves domain accountability and release velocity.
Compile stable decision logic and retain retrieval for explanation and residual ambiguity.
Ask a model to interpret the source document for every request.
Cost acceptedRule compilation needs controlled change, but creates repeatable decisions, regression tests and clear exceptions.
Retries are bounded by knowledge of business effect; unknown outcome remains visible, owned and independently reconciled.
Actual thresholds belong to accountable service owners. The design exposes the equations and observables that those owners must baseline.
compile_work = changed_sources x affected_rules x dependent_routesserving_qps = knowledge_requests x candidate_fragmentsrevalidation_scope = changed_dependencies x linked_test_setsUse customer holdings only when necessary for the current explanation and keep external or assumed circumstances visibly separate.
A design is production-ready only when teams can prove what happened, recover it and change it safely.
product and rule applicability
guidance-versus-advice boundary
superseded-content withdrawal
calculation and citation verification
Document versions, effective periods, agreement facts, authority ranking, conflict rationale, owner decision and customer communication.
Product or legal owners determine the governing interpretation and any remediation.
Start with high-consequence rules and stable documents. Expand automation only where extraction corrections and owner decisions show repeatable structure.
Product, conduct, legal, tax, knowledge and advisory owners define the permitted answer boundary.