data2dsl

Ticket 004: Define data comparison contract v0

• ID: ticket-004
• Owner: unresolved:human
• Status: DONE
• Workflow state: DONE
• Created: 2026-08-17

Goal and scope

Define the smallest local, experimental data2dsl comparison contract v0 for the golden case: compare a work-summary.md claim with GitHub activity for the same repository, actor, metric and half-open UTC time window.

The contract must compose the existing wellmanifest/dsl query, observation and result profiles by immutable reference. It adds only data2dsl-owned domain semantics: canonical scalar/set values, evidence locators, comparability, outcomes and typed deltas. It remains descriptive and effect-free.

Out of scope: changing subactor/twin, wellmanifest/dsl or another repository; implementing source adapters, GitHub acquisition, an LLM layer or an enforcing runtime; adding a runtime dependency; publishing a stable API.

Acceptance criteria

• AC-01: A closed JSON Schema defines query, observation and comparison result documents for scalar and string-set values.
• AC-02: The contract pins and maps to the current immutable wellmanifest/dsl reusable profiles instead of copying their schema.
• AC-03: Outcomes cover MATCH, CONFLICT, MISSING_LEFT, MISSING_RIGHT and UNEVALUABLE, separately from observation state.
• AC-04: Evidence preserves locator, immutable source revision, media type, SHA-256, extractor identity/version and optional location.
• AC-05: Golden conflict and match fixtures use identical subject, metric and window keys and pass deterministic validation.
• AC-06: Invalid cross-key, ordering, digest and outcome/delta combinations are rejected by self-tests.
• AC-07: The pinned wellmanifest/dsl checker accepts the local DSL manifest and the data2dsl governance gate passes.

Result

The experimental contract lives in src/data2dsl_contract_v0. It composes the immutable Wellmanifest query, observation and result profiles, defines a closed data2dsl comparison bundle, and proves all five outcomes plus five negative invariants without accessing a source network or changing another repository.

The contract is integrated on the default branch at 3c747c1b1d79426196fd4bb0b5dc42360d88a066 through GitHub PR 4.

Participants

• Human participant: unresolved; no user-* file was created by this script.
• Agent participant: ai-codex.md