Manifest and problem-contract compatibility

Parsing establishes the shape of each manifest and problem contract. The pure validate_manifest_compatibility pass then resolves relationships among those typed documents before planning, materialization, or worker launch.

The caller supplies parsed problem contracts keyed by their manifest-local problem names. The validator requires a contract for every problem definition, then checks that:

• every implementation's problem-contracts entry names a defined problem;
• every experiment selects defined datasets, implementations, execution policies, and observation policies;
• every selected implementation declares the experiment's problem contract;
• every selected dataset's output-schema is one of the problem contract's accepted dataset-schemas;
• the selected timing scope is allowed by the problem contract;
• the observation policy's scientific budget is supported by the problem; and
• each implementation declares the capability required by the observation kind.

Version 1 has one observation kind: one_shot. It requires the one_shot implementation capability and the none scientific budget. These relationships are validated explicitly even though the version-1 parsers also narrow each individual document to those values.

Dataset binding

A contract with an empty dataset-schemas list is dataset-free. Its experiments must omit datasets; that empty selection instructs the later planner to bind exactly one versioned, built-in unit dataset. Selecting a user dataset for such a problem is an error.

A contract with one or more accepted dataset schemas requires every experiment to select at least one dataset. Multiple selections remain separate bindings, and each selected definition must emit an accepted schema. Metewand compares the normalized repository schema references exactly—it never infers a conversion from fields, dimensions, or similar structure.

Timing-policy invariants

The compatibility pass applies the version-1 defaults relevant to timing:

• worker-reuse: false;
• warmup-runs: 0; and
• timing-scope: "prepare_and_execute".

Process-local warm-ups require worker-reuse: true. The cold_end_to_end scope instead requires worker-reuse: false and warmup-runs: 0, because every measured slot must include a fresh worker launch.

use std::collections::BTreeMap;

use metewand_core::{
    compatibility::validate_manifest_compatibility,
    manifest::Manifest,
    problem_contract::ProblemContract,
};

# fn check(
#     manifest: &Manifest,
#     contracts: &BTreeMap<metewand_core::manifest::Name, ProblemContract>,
# ) -> Result<(), Box<dyn std::error::Error>> {
validate_manifest_compatibility(manifest, contracts)?;
# Ok(())
# }

The pass returns the first error in deterministic problem, implementation, execution-policy, and experiment order. It does not read contract files, load schemas, expand parameter grids, construct unit-dataset records, or launch workers. Those operations retain their own explicit boundaries.

The subsequent side-effect-free logical plan pairs every selected implementation capability with declared evidence. verified_now is reserved for a capability observed by the current operation, and previously_verified describes evidence loaded from an earlier resolution. Neither stronger state can originate in this compatibility or planning pass.