0.1a — Establish the shared SchemaPackage as the single source of truth for all five config/artifact schemas #15

Acceptance Criteria

• A well-formed lab.toml, SolveSpec, manifest.toml, result.toml, and catalog-entry each validate against their schema via the package's single validate() entrypoint.
• A malformed artifact (missing required key, wrong type, out-of-range value, unknown key) fails validation with an error that names the offending key and its path.
• Every schema carries a schema_version; an artifact whose schema_version is absent or unrecognized is rejected (not silently accepted as current).
• A manifest.toml whose FINISHED field carries a {status, exitCode} outside the allowed terminal-status set fails validation against the run-dir-contract shape.
• The CI fast tier validates committed fixtures for all five artifacts against the package and fails the PR on any nonconformance.
• A Julia-emitted result.toml and manifest.toml round-trip: emitted by the solver path, then validated against the SAME schema files in CI (no second, transcribed copy).
• SolveSpec's requires (packages + symbols, load mechanism, julia patch) and lab.toml's provides (image/depot, julia version, loadable packages, license) are schema-validated; validate() rejects a SolveSpec whose requires are not satisfied by the target lab's provides — e.g. the DRAFT feat(template): verified Piccolissimo solve template (beta target) + integration contract #24 case (requires using-loadable Piccolissimo + CairoMakie; lab provides an image-only depot without CairoMakie) fails before any run.
• The Julia round-trip is exercised against a real binary-backed runtime (the shipped pkgimage), not only a source Pkg.develop env, so an artifact that validates only under source is caught.
• The extension and amico-run both obtain validation only from this package's validate(); a consumer that reintroduces its own schema definition is a regression.
• The catalog-entry schema validates a representative promote-shaped record even though no store consumes it yet.

Key Decisions

• JSON Schema is the single source of truth; one validate() shared across CLI, extension, CI, and a Julia round-trip (PRD Schema-package decision; resolves Q86).
• All five schemas (lab.toml, SolveSpec, manifest.toml, result.toml, catalog-entry) live in SchemaPackage; SolveSpec is validated here even though it is assembled in amico-run.
• schema_version lives on every artifact; manifest.toml is the per-run version + provenance carrier.
• FINISHED is the run-dir's terminal sentinel ({status, exitCode}), modeled as a sub-shape of the run-dir contract, not a peer schema with its own schema_version.
• This package formalizes β.1's prose + emitter-code run-dir contract into versioned machine-checkable schemas; it supersedes the informal contract, not any pre-existing validators (β has none).
• catalog-entry schema is in-scope here; its store/consumer is Phase 3.

Constraints & Invariants

• The schemas must encode β.1's emitted run-dir contract exactly — formalize, do not fork it.
• One validator path only: a consumer adding its own schema definition is a regression.
• The Julia round-trip must use the same schema files as the TS consumers, not a transcription.

Source

Phase 0-prime task 0.1 (SchemaPackage, 6 pd), sliced to 0.1a (the full five-schema SET + shared validate() + CI fast-tier conformance + Julia round-trip); plan-20260603 §3 Phase 0'. Realizes S14 (versioned schema per config/artifact), S15 (machine-checkable validate()), S16 (CI conformance + Julia round-trip of emitted artifacts). Resolves Q86 (schema home / cross-language sharing). Partially resolves Q87 (per-artifact schema_version on all five artifacts; migration maps deferred to the first bump). Related: #1 (β.1 emits the contract this formalizes), sibling 0.1b (the S17 lab.toml on-load field-precise error UX), 3.1 CatalogStore (the catalog-entry consumer, Phase 3).

Notes

This slice is the dependency-graph root for Phase 0-prime — its consumers (lab.toml on-load UX 0.1b, CatalogStore 3.1) gate on it. The plan treats 0.1 SchemaPackage as one 6-pd task; this split keeps the full schema SET (all five, incl. SolveSpec) + shared validate() + CI conformance + Julia round-trip together in 0.1a as one coherent vertical slice, and carves out ONLY the distinct S17 lab.toml on-load field-precise-error behavior as 0.1b. Do not merge them and do not pull the catalog STORE or HDF5 export forward.

Testing

TDD applies (RED->GREEN): write failing validation cases first. Extend the CI fast tier's schema-validation suite (committed-fixture conformance across all five artifacts + the Julia round-trip emit-then-validate); add the per-field/per-constraint negative matrix asserting the error names the offending field. No prescribed test names — the tdd loop decides structure.