{"schema_version":1,"experiment_id":"eoa_inverse_innovation_exp06_four_proposal_generalization60_20260803","cell_id":"representation_independent_interface_contract__environmental_climate","arm":"COMPLETE_PROPOSAL_PORTFOLIO","candidate_id":"p02-snowpack-process-module-contract","proposal_index":2,"version":0,"title":"Conservation-Bound Contract for Substitutable Snowpack Process Modules","problem":"In a coupled watershed or land-surface simulation, the host model may read and modify a snow module's internal layer arrays, phase partitions, solver timesteps, or diagnostic fields. Those details then become an unofficial interface. Replacing a single-layer module with a multilayer, adaptive-mesh, vectorized, or accelerator-backed implementation can consequently require host-model changes or alter boundary flux handling even when the replacement is intended to realize the same declared snow-process semantics.","actors":["Snow-process scientists who specify the modeled behavior","Land-surface and watershed model developers who call the snow component","Numerical-method developers who implement alternative solvers and discretizations","Model integration lead who governs component acceptance","Research-computing engineers who optimize implementations","Experiment leads who interpret simulated runoff and surface-energy results","Independent model reviewers who inspect conservation and reproducibility evidence"],"observable_state":"The candidate problem is observable when host-model code indexes snow layers, mutates module-owned arrays, assumes a fixed layer count or update order, reads undocumented diagnostics, or relies on solver-specific errors. It is also observable by applying identical initial abstract state and forcing sequences to two purportedly equivalent implementations: differences outside predeclared tolerances in total stored water, energy, boundary fluxes, checkpoint behavior, or error categories indicate either nonconformance or an underspecified contract.","consequence":"A change in snow-layer representation, numerical solver, execution device, or internal timestep can unintentionally change water and energy exchange with the host model, introduce conservation residuals, or break integration code. Researchers may then be unable to distinguish an intended scientific change from a representational or coupling change, while potentially useful implementations remain difficult to substitute.","affected_objective":"Permit controlled replacement and optimization of a declared snow-process component while preserving its public state-transition semantics, conservation obligations, and reproducibility at the host-model boundary.","intervention":"Define an opaque Snowpack Column component whose abstract state consists of simulation time, total ice and liquid water stores, total snow energy relative to a declared reference, footprint support, parameter-set identity, and accumulated boundary-flux ledger. Public operations are: create a column from valid abstract totals and metadata; advance it over a declared interval using typed meteorological and surface-boundary forcing; observe contracted totals and diagnostics; checkpoint and restore abstract state; and close the component. Each advance returns boundary fluxes and a new state version rather than exposing internal layers. Preconditions specify units, time support, forcing completeness, parameter version, admissible ranges, and monotonic simulation time. Postconditions require nonnegative water stores, declared mass and energy closure within fixed numerical tolerances, consistency between returned fluxes and the flux ledger, and reproducible checkpoint continuation in deterministic mode. Invalid inputs return stable error categories and leave state unchanged. Layer count, layer order, mesh adaptation, phase arrays, solver stages, caches, parallel decomposition, and CPU or accelerator representation are non-contractual. A shared conformance oracle combines limiting-case examples, generated forcing sequences, conservation properties, warranted metamorphic relations, checkpoint tests, and leakage probes. An implementation is substitutable only for the same contract and parameter-set versions, within predeclared semantic and resource tolerances; a scientifically different process formulation requires a distinct contract version or component identity.","structural_mapping":[{"archetype_element":"Clients dependent on a component","domain_realization":"A watershed or land-surface host model depends on a snowpack process module for state transitions and boundary fluxes."},{"archetype_element":"Abstract operation surface","domain_realization":"Create, advance, observe, checkpoint, restore, and close are the only supported interactions with a snowpack column."},{"archetype_element":"Abstract state model","domain_realization":"The public state is expressed as time, footprint, total water stores, total energy, parameter identity, and boundary-flux accounting rather than as snow layers."},{"archetype_element":"Hidden representation","domain_realization":"Layer discretization, solver stages, internal timestep, parallel layout, caches, and hardware-specific arrays remain private."},{"archetype_element":"Behavioral laws and invariants","domain_realization":"Public transitions preserve nonnegative stores, time continuity, mass and energy accounting, flux-ledger consistency, and deterministic checkpoint continuation within declared tolerances."},{"archetype_element":"Error and side-effect limits","domain_realization":"Malformed or inadmissible forcing produces a stable error without advancing time, partially changing state, mutating host arrays, writing undeclared files, or consuming an undeclared global random stream."},{"archetype_element":"Abstraction function","domain_realization":"Each valid internal layer or mesh state maps to the contracted total stores, energy, time, footprint, and flux ledger observed by the host."},{"archetype_element":"Conformance oracle","domain_realization":"The same black-box tests exercise conservation, edge cases, generated transition sequences, checkpoints, errors, and observable leakage for every implementation."},{"archetype_element":"Substitutability rule","domain_realization":"Only implementations conforming to the same behavioral and parameter versions and remaining within preset numerical and resource tolerances may replace one another."},{"archetype_element":"Versioned stewardship","domain_realization":"The model integration lead reviews public semantic changes, while private solver or representation changes remain unrestricted when conformance is preserved."}],"mechanism_mapping":[{"mechanism_slug":"abstract_data_type_specification","role":"Specifies a snowpack column through abstract stores and transitions, then maps valid layer-, mesh-, or solver-specific states to that meaning using a representation invariant and abstraction function.","counterfactual_removal":"Without the abstract state and mapping, total stores would merely be selected diagnostics and could not certify that different internal representations realize the same component."},{"mechanism_slug":"design_by_contract_clause","role":"Defines caller obligations for forcing and time intervals, component obligations for conservation and returned fluxes, and the state-preserving policy for invalid calls.","counterfactual_removal":"Without per-operation clauses, implementations could accept the same signatures while differing silently on missing forcing, time discontinuities, invalid ranges, and partial failure."},{"mechanism_slug":"interface_definition_language","role":"Declares typed operations, quantities, units, state handles, flux results, checkpoint tokens, and stable error categories independently of programming language and implementation.","counterfactual_removal":"Without a compiled public surface, the host could continue importing solver-specific structures or hardware-specific array types despite the prose contract."},{"mechanism_slug":"opaque_type_or_module_boundary","role":"Makes snow layers, phase arrays, solver objects, and caches unreachable to the host, forcing all interaction through the declared state-transition operations.","counterfactual_removal":"Without opacity, direct layer access would recreate the representation coupling that prevents a different discretization from substituting."},{"mechanism_slug":"black_box_contract_test_suite","role":"Runs the same limiting cases, transitions, checkpoint continuations, error cases, and flux comparisons against each candidate implementation.","counterfactual_removal":"Without a shared black-box gate, acceptance would depend on implementation-specific regression tests that could preserve internal traces rather than public behavior."},{"mechanism_slug":"property_based_conformance_test","role":"Generates admissible and inadmissible forcing sequences to test nonnegative stores, time monotonicity, mass and energy closure, flux-ledger consistency, and state preservation after errors.","counterfactual_removal":"Without generated transition sequences, conservation defects triggered by unusual combinations of forcing and checkpoint operations could escape a finite catalog of examples."},{"mechanism_slug":"metamorphic_behavior_test","role":"Checks contract-derived relations such as physical-unit conversion invariance, zero-duration identity, checkpoint-and-restore continuation, and equivalence under representationally different encodings of the same forcing.","counterfactual_removal":"Without relational tests, important behavior would require exact expected trajectories even where only cross-run laws can be stated independently of the numerical implementation."},{"mechanism_slug":"representation_leakage_probe","role":"Varies internal layer counts, execution devices, allocation layouts, and solver configurations while checking whether ordering, error text, token contents, timing classes, or undeclared diagnostics expose those choices.","counterfactual_removal":"Without leakage probing, the host could develop dependencies on observable solver accidents even though private arrays were structurally inaccessible."},{"mechanism_slug":"semantic_versioning_and_deprecation_gate","role":"Separates compatible implementation changes from breaking changes to state meaning, tolerances, forcing semantics, or public diagnostics and inventories affected host models before removal.","counterfactual_removal":"Without version governance, a scientific or semantic change could masquerade as a private optimization and make prior experiments irreproducible."},{"mechanism_slug":"substitutability_trial_or_canary","role":"Runs a candidate module in shadow on a bounded benchmark simulation, compares contracted fluxes, conservation residuals, runtime, and resource use against preset thresholds, and prevents promotion after a breach.","counterfactual_removal":"Without a staged shadow trial, offline unit cases would not test integration under realistic forcing sequences, host call patterns, concurrency, and resource contention."}],"causal_chain":["The host model accesses snow-module layers, arrays, update order, or solver-specific diagnostics because the required behavior is not fully stated at an abstract boundary.","Those reachable or observable details become assumptions embedded in host calculations and experiment tooling.","A proposed solver, discretization, or hardware implementation changes one of those details while intending to preserve the same public snow process.","The embedded assumptions cause integration failure, altered boundary-flux accounting, or a result change that cannot be attributed cleanly to science versus representation.","The intervention replaces layer-level access with opaque column handles, explicit transitions, conservation laws, errors, and side-effect limits.","A shared oracle judges each implementation through abstract stores, fluxes, checkpoints, and laws rather than internal trajectories.","Conforming representations can then be substituted under the same scientific contract, while genuine process-formulation changes must be identified and versioned explicitly."],"baseline":"Retain a canonical snow-module implementation and its layer arrays, require new solvers to reproduce that internal layout, maintain bespoke adapters for each alternative, and compare a small set of end-of-run hydrographs or energy summaries manually. This preserves existing integration code but treats the incumbent representation as the effective specification and provides weak localization of discrepancies.","nearest_rivals":["Mandate one common internal layer structure for every snow model; this eases host integration but prevents representations with different meshes or solver state.","Define only a shared forcing-and-flux file format; this standardizes exchanged fields but not state transitions, failure behavior, checkpoint semantics, conservation laws, or side effects.","Write a bespoke adapter for each snow implementation; this translates representations pairwise but supplies no common acceptance oracle or general substitution rule.","Compare complete model outputs after each replacement; this may reveal a difference but does not isolate whether it arose from snow semantics, host reach-through, numerical representation, or unrelated coupled feedback.","Refactor the entire host and snow code into one monolithic implementation; this can remove an immediate boundary mismatch but eliminates independent component substitution.","Require every candidate to match the incumbent's internal numerical trace; this supplies a strong regression target but freezes solver-specific behavior rather than preserving only the abstract contract."],"remaining_contrastive_claim":"The proposal is distinguished by treating a snowpack process as an opaque, stateful scientific component governed by transition laws, conservation invariants, error semantics, and one representation-independent oracle. Neither a common data format nor a common layer layout provides this combination, and the contract does not declare scientifically different snow formulations interchangeable.","authority_safety":{"decision_authority":"The model integration lead may authorize an isolated contract prototype and shadow benchmark. Snow-process scientists must approve the abstract quantities, conservation equations, tolerances, and parameter identity. The experiment lead retains authority over any production model substitution, published rerun, or reinterpretation of scientific results.","authorized_first_step":"On an isolated development branch, wrap one idealized single-column snow case behind a draft opaque interface, implement an adapter for the incumbent module and an independent simplified test implementation, and run a frozen forcing sequence plus generated edge cases without changing an operational model configuration or published experiment.","excluded_actions":["Replacing a module in a production, operational, regulatory, or publication-bound simulation","Changing forcing data, calibration parameters, or scientific equations to make a candidate pass","Treating behavioral conformance as evidence that the snow formulation is empirically valid","Reclassifying a scientifically different formulation as a compatible implementation change","Publishing benchmark differences as climate findings","Allowing the prototype to write into canonical experiment archives or overwrite checkpoints","Setting numerical or resource tolerances after examining candidate results"],"halt_rollback":"Halt if the prototype writes outside its sandbox, violates a conservation bound, requires exposing private layer state to express a host need, produces nondeterministic checkpoint continuation in declared deterministic mode, or reveals that the incumbent and proposed contract use incompatible scientific meanings. Disable the candidate adapter, restore the frozen incumbent configuration, retain the failing inputs and non-sensitive comparison log, and make no change to canonical experiments."},"negative_tests":{"strongest_counterevidence":"The host may already interact only through documented totals and fluxes, with no layer-level reach-through, while independently implemented discretizations pass common conservation and checkpoint tests under the same semantics. That would undermine the inferred representation-coupling problem for the selected component.","problem_falsifier":"The problem is falsified for the bounded case if a dependency inventory finds no host or tooling reliance on internal representation and a solver or discretization change can be made without host edits or discrepancies in contracted stores, fluxes, errors, side effects, and checkpoints.","intervention_falsifier":"The intervention fails if scientifically necessary host behavior cannot be expressed without exposing layer structure, or if two implementations pass the complete draft oracle yet differ outside the predeclared tolerance on a contracted boundary flux or conservation result during the frozen shadow benchmark.","risks":["The abstract state may omit a scientifically necessary quantity and falsely classify nonequivalent modules as substitutes.","Overly strict numerical tolerances may freeze the incumbent solver, while loose tolerances may admit consequential divergence.","Conservation properties are necessary but do not establish empirical validity or complete physical correctness.","A simplified independent implementation may share assumptions with the incumbent and fail to expose a common defect.","Opaque state may impede legitimate diagnosis unless sanctioned, non-contractual diagnostic access is carefully separated.","Generated forcing may remain concentrated in easy regions and miss unstable transitions.","Resource thresholds may exclude useful implementations or conceal hardware-specific bottlenecks if poorly chosen.","Contract versioning could be used to label semantic changes without providing adequate experiment migration evidence."]},"next_evidence_step":"Select one non-operational, idealized snow-column benchmark with a frozen initial abstract state and forcing series. Before running candidates, record the public operations, mass and energy accounting equations, admissible input ranges, deterministic-mode rule, stable error categories, numerical tolerances, resource thresholds, and allowed diagnostics. Implement an incumbent adapter and an independently coded simplified implementation, then run limiting cases, generated forcing sequences, unit-conversion relations, invalid-call tests, checkpoint continuations, and one shadow integration with the host. Classify every discrepancy as a contract omission, adapter defect, implementation defect, incompatible scientific meaning, or evidence against the proposed problem; do not promote either implementation or alter a canonical experiment.","prior_art_status":"UNSEARCHED","diversity_from_prior_proposals":"Proposal 1 addressed a wetland monitoring evidence ledger whose clients depended on workbook, table, raster, revision, quality-control, and aggregation representations. This proposal addresses direct coupling between a dynamic snow-process simulator and a host model through internal layer and solver state. Its intervention is an opaque timestep-transition component governed by physical conservation, numerical tolerances, checkpoints, and shadow simulation, rather than an observation ledger governed by evidence lineage, corrections, quality decisions, and as-of queries. Its causal path runs from host reach-through into process representation to flux or conservation discrepancies during solver substitution; proposal 1 ran from analytical dependence on record layout to altered inclusion, revision, or aggregation during data-backend migration. The proposal is independently adoptable by a modeling team without changing any monitoring-record system.","revision_record":{"parent_version":null,"progress_targets_addressed":["Generated a second complete proposal with a problem, intervention, and causal path materially distinct from proposal 1.","Preserved the representation-independent behavioral-contract structure in a dynamic environmental simulation context."],"conceptual_changes":["Initial version; no parent revision.","Shifted the abstract component from a versioned observational evidence ledger to a thermodynamic snowpack state-transition module."],"operational_changes":["Specified an isolated single-column benchmark, two independent implementations, generated transition tests, and a bounded host-model shadow run."],"evidence_changes":["Defined observable reach-through indicators, conservation and checkpoint comparisons, strongest counterevidence, and separate problem and intervention falsifiers."],"claim_changes":["Limited substitutability to implementations of the same scientific contract and parameter version.","Made no novelty, prevalence, demand, empirical-validity, or effect-size claim."]}}