nf.motion.flow_control

Flow Control Normal Form (FCNF)

Contract ID: nf.motion.flow_control | Family: motion | Index Status: draft | AuthorityEffect: None

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1. Executive Summary & Metadata

Flow Control Normal Form (FCNF) enforces structural normalization and explicit defect routing in the motion regime.

Property	Value
Canonical ID	nf.motion.flow_control
Short Name	FCNF
Full Name	Flow Control Normal Form
Family	motion (Flow Control, Horizon Emission & Lieb-Robinson Locality Bounds)
Qualification	Extended Form Contract (Normal Form Contract)
Data / Math Posture	in_motion
Index Status	draft
Theory Status	proposed
Verification Status	absent
Contract Version	v0
Governance Fence	AuthorityEffect: None (certified_implies_authorized: false)

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2. Visual Architecture & Normalization Diagram

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3. Concrete Worked Example & Mechanism

Visual Transition Summary

Stage	Carrier / Operator	Concrete State / Invariant
1. Before / Candidate Input	Input Carrier (FCNF Candidate)	Anomaly risk: silent stream loss ; lag reorder duplication or ; overflow while presenting a lan...
2. Normalization / Gate	FCNF Verification Gate	every moving record decla... (certified_implies_authorized: false)
3. After / Certified Output	Certified FCNF Output	Invariant: ['ordering_key', ; 'offset', 'watermark', ; 'capacity_budget',...

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4. The Four-Pillar Quadrilateral & Non-Claims

Every contract in simplex-normal-forms is evaluated against the Four-Pillar Quadrilateral defined in contracts/_golden_nfs/standard.yaml:

Pillar	Requirement	Contract Specification for nf.motion.flow_control
Pillar I: Excludes Anomaly	Name and eliminate a specific class of data or state defects.	silent stream loss lag reorder duplication or overflow while presenting a lane as exact
Pillar II: Preserves Invariant	State the structural invariant and protected skeleton preserved across transitions.	Invariant: every moving record declares ordering capacity backpressure drop and replay semantics Protected Skeleton: ['ordering_key', 'offset', 'watermark', 'capacity_budget', 'backpressure_policy', 'drop_policy', 'replay_window']
Pillar III: Lossless Reconstruction	State the non-loss reconstruction operator (join, direct sum, pullback, or replay).	Lossless reconstruction under declared projection, direct sum, or pullback operators.
Pillar IV: Syntactic Decidability	State how conformance is decided from declared constraints without unbudgeted scans.	Decidable from declared schema and witness metadata within bounded evaluation budgets.

Explicit Non-Claims (certified_implies_authorized: false)

• does not support semantic correctness of payloads
• does not certify downstream repair without BQNF on the affected observer boundary
• does not authorize side effects produced by the stream consumer

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5. Operational Verification & Terminal Routing

5.1 Required Declarations

• event_identity
• ordering_key
• offset_or_sequence_number
• watermark_rule
• capacity_budget
• backpressure_policy
• drop_policy
• replay_window
• duplicate_handling_rule

5.2 Required Evidence

• offset_log
• watermark_trace
• enqueue_dequeue_ack_records
• retry_or_drop_ledger
• capacity_measurements

5.3 Validation Criteria

Criterion ID	Name	Condition
criterion	Check	offsets are monotone within each declared ordering key
criterion	Check	late events are routed by watermark policy rather than silently merged as current
criterion	Check	dropped or compacted events have a loss ledger
criterion	Check	backpressure terminal is emitted before capacity overflow is treated as successful delivery

5.4 Terminal Route Map

Every evaluation terminates in a declared local route mapped to a canonical terminal in standard.yaml:

Local Terminal Route	Canonical Terminal
FlowOk	Escalate
BackpressureRequired	Serialize
DropLedgerRequired	Escalate
ReorderViolation	Reject
DuplicateSuppressed	Repair
CapacityExceeded	Refuse
ReplayWindowExpired	Refuse

5.5 Declared Failure Modes

• symptom: consumer sees a current aggregate after queue overflow dropped events, diagnosis: unledgered stream loss, terminal: DropLedgerRequired
• symptom: watermark advances past late data then read model accepts the late data as fresh, diagnosis: nonmonotone freshness boundary, terminal: ReorderViolation

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6. Epistemic Claim Hygiene Quadrant

In accordance with the repository's epistemic claim discipline:

1. What it supports:
   • Supports syntactic and operational checking of nf.motion.flow_control (FCNF) against its declared schema, boundary constraints, and witness obligations in this model.
   • Supports deterministic terminal routing (FlowOk, BackpressureRequired, DropLedgerRequired, ReorderViolation) when required declarations or invariants fail.
2. What it does not support:
   • Does not confer operational authority (AuthorityEffect: None, certified_implies_authorized: false).
   • Does not claim semantic truth of undeclared external processes or unverified upstream inputs beyond the declaredprotected skeleton.
3. The narrowest defensible claim:
   • Within the declared substrate in_motion, this contract enforces that silent stream loss lag reorder duplication or overflow while presenting a lane as exact is either excluded under every moving record declares ordering capacity backpressure drop and replay semantics or routed to an explicit refusal/recovery terminal.
4. The next test needed:
   • Property-based falsification and mutation testing across boundary edge cases and composed multi-step pipelines for nf.motion.flow_control.

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7. Canonical YAML Contract (contracts/nf.motion.flow_control.yaml)

Click to expand full canonical YAML contract (contracts/nf.motion.flow_control.yaml)

schema_version: smplx.nf.contract.v0
contract_kind: normal_form_contract
identity:
  id: nf.motion.flow_control
  name: Flow Control Normal Form
  short_name: FCNF
  version: v0
  status: draft
  family: motion
  theory_status: proposed
  contract_status: draft
  verification_status: absent
classification:
  hierarchy_level: normal_form
  subject_kind:
  - event_stream
  - flow_lane
  - distributed_write
  data_posture: in_motion
  mathematical_posture: operational
purpose:
  excludes_anomaly: silent stream loss lag reorder duplication or overflow while presenting
    a lane as exact
  preserves_invariant: every moving record declares ordering capacity backpressure
    drop and replay semantics
  protected_skeleton:
  - ordering_key
  - offset
  - watermark
  - capacity_budget
  - backpressure_policy
  - drop_policy
  - replay_window
  erased_structure: []
  non_claims:
  - does not support semantic correctness of payloads
  - does not certify downstream repair without BQNF on the affected observer boundary
  - does not authorize side effects produced by the stream consumer
obstruction_substrate:
  policy_ref: ../substrate/default_finite_obstruction_policy.yaml
  finite_carrier:
    description: finite ordered event lane with offsets watermarks capacity windows
      retries and drops
  cochain_complex:
    C0: retry_reorder_watermark_or_backpressure_repairs
    C1: loss_lag_duplicate_reorder_or_overflow_defects
    C2: nonmonotone_watermark_capacity_or_replay_closure_failures
    d0: repair_to_stream_defect
    d1: stream_defect_to_closure_failure
    quotient: Q1 = C1 / im(d0)
  obstruction_class:
    notation: '[omega]'
    exact: '[omega] == 0'
    residual_closed: '[omega] != 0 and d1(omega) == 0'
    open: d1(omega) != 0
  carrier_realization: ordered_stream
  geometry_module: null
  gauge_metric_selector: null
declarations_required:
- event_identity
- ordering_key
- offset_or_sequence_number
- watermark_rule
- capacity_budget
- backpressure_policy
- drop_policy
- replay_window
- duplicate_handling_rule
evidence_required:
- offset_log
- watermark_trace
- enqueue_dequeue_ack_records
- retry_or_drop_ledger
- capacity_measurements
validation_criteria:
- offsets are monotone within each declared ordering key
- late events are routed by watermark policy rather than silently merged as current
- dropped or compacted events have a loss ledger
- backpressure terminal is emitted before capacity overflow is treated as successful
  delivery
proof_obligations: []
terminal_routes:
- FlowOk
- BackpressureRequired
- DropLedgerRequired
- ReorderViolation
- DuplicateSuppressed
- CapacityExceeded
- ReplayWindowExpired
certification:
  certificate_required: true
  certificate_kind: flow_control_certificate
  obstruction_class_required: true
  loss_ledger_required: conditional
  verifier_required: true
authorization:
  authorized_by: null
  certified_implies_authorized: false
failure_modes:
- symptom: consumer sees a current aggregate after queue overflow dropped events
  diagnosis: unledgered stream loss
  terminal: DropLedgerRequired
- symptom: watermark advances past late data then read model accepts the late data
    as fresh
  diagnosis: nonmonotone freshness boundary
  terminal: ReorderViolation
references:
- ../1_normal_forms.md
- ../symbol_dictionary.md
terminal_route_map:
  FlowOk: Escalate
  BackpressureRequired: Serialize
  DropLedgerRequired: Escalate
  ReorderViolation: Reject
  DuplicateSuppressed: Repair
  CapacityExceeded: Refuse
  ReplayWindowExpired: Refuse
definition:
  source: coda_all_universe/mssn_sn_tower/definitions.md
  formal_statement: silent stream loss lag reorder duplication or overflow while presenting
    a lane as exact. every moving record declares ordering capacity backpressure drop
    and replay semantics
  quadrilateral:
    qualifies_as_true_normal_form: false
    qualification_gap: reconstruction_is_not_a_relational_project_join
    anomaly_exclusion: silent stream loss lag reorder duplication or overflow while
      presenting a lane as exact
    lossless_join:
      status: declared_reconstruction
      statement: every moving record declares ordering capacity backpressure drop
        and replay semantics
    dependency_preservation:
      status: declared_with_the_invariant
      statement: The preserved invariant stays on the declared schema. This form does
        not state a functional-dependency projection of a flat relvar decomposition.
    syntactic_decision:
      status: declaration_decidable
      statement: The check reads the declared constraints and validation criteria.
        One unrecorded runtime image is not the decider.
schema_ref: ./normal_form_contract_schema.yaml