Bundled envelope JSON Schema

message-envelope.schema.json in this directory is a verbatim copy of the canonical BabelQueue wire-envelope schema (schema_version 1). It is bundled so an app can validate a decoded envelope offline, at runtime, via SchemaValidator — no network access and no JSON-Schema library required (GR-7: zero heavy dependencies).

Provenance & drift policy

The schema is copied along this chain, each link byte-identical to the last:

.ssot/contracts/message-envelope.schema.json   ← canonical source of truth
  → conformance/schema/message-envelope.schema.json   (cross-SDK suite)
    → tests/conformance/schema/message-envelope.schema.json   (vendored; CI diffs this)
      → src/Validation/message-envelope.schema.json   (this file; ships in the package)

CI's conformance job diffs the vendored tests/conformance/schema/ copy against the canonical suite, so that copy can never silently drift. Keep this src/ copy byte-identical to the vendored one (tests/conformance/schema/message-envelope.schema.json) — a test asserts they match. If the contract changes (which requires an ADR + a schema_version decision), update both copies in the same change. The contract is authoritative: if they ever disagree, this copy is wrong, not the contract.