Add structural-history Echo package descriptor

CHANGELOG.md

@@ -9,6 +9,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 ### Added
 
+- **Structural-history Echo package descriptor**: Graft now carries a
+  deterministic descriptor for the structural-history package it expects Echo
+  to host later, with repo-root-relative schema and generated-artifact
+  identities, descriptor-only Echo posture, and a local drift check wired into
+  `pnpm schema:structural-history:check`.
 - **Structural history schema authority**: Graft now carries a canonical
   `schemas/graft-structural-history.graphql` schema with Wesley-generated
   TypeScript contracts and a deterministic artifact drift check, establishing

docs/design/CORE_graft-structural-history-echo-package-descriptor.md

@@ -0,0 +1,99 @@
+# CORE graft structural-history Echo package descriptor
+
+## Status
+
+Active slice.
+
+## Hill
+
+Graft publishes a deterministic, repo-local descriptor for the
+structural-history contract package it expects Echo to host later, without
+requiring any Echo runtime behavior in this slice.
+
+## Why this slice does not require Echo changes
+
+Echo is the substrate target. This slice only records the package facts Graft
+will eventually hand to that substrate:
+
+- package identity;
+- schema identity;
+- generated TypeScript artifact identity;
+- Wesley generator identity;
+- exposed structural-history record, evidence, and operation names;
+- explicit descriptor-only Echo posture.
+
+No package is installed into Echo. No Echo storage, replay, query execution, or
+TypeScript client binding is invoked. The descriptor is therefore a Graft-owned
+contract artifact, not an Echo feature request.
+
+If a later slice discovers that Echo cannot accept this package shape, that
+becomes a separate Echo planning item with concrete evidence. This slice should
+not pre-emptively expand Echo.
+
+## Acceptance Criteria
+
+1. Graft has a checked-in structural-history Echo package descriptor.
+2. The descriptor is deterministic and derived from existing schema authority
+   facts plus `package.json` identity.
+3. Descriptor paths are repo-root-relative and never machine-local absolute
+   paths.
+4. `pnpm schema:structural-history:check` fails when the descriptor drifts.
+5. The descriptor explicitly states that Echo runtime installation and package
+   installation are not required in this slice.
+
+## Descriptor Surface
+
+Descriptor path:
+`schemas/graft-structural-history.echo-package.json`
+
+The descriptor records:
+
+| Section | Meaning |
+| :--- | :--- |
+| `descriptorVersion` | Version of the descriptor format itself. |
+| `package` | Graft-owned Echo package identity and source package version. |
+| `schema` | GraphQL schema path, hash, and Wesley L1 registry hash. |
+| `generatedArtifacts` | Wesley-generated TypeScript artifact path, hash, and generator version. |
+| `echo` | Descriptor-only Echo posture for this slice. |
+| `contracts` | Required record types, evidence labels, and operation constants. |
+
+## Drift Model
+
+The descriptor is checked by
+`scripts/check-structural-history-echo-package.ts`.
+
+The checker rebuilds the expected descriptor from:
+
+- `schemas/graft-structural-history.manifest.json`;
+- `package.json`.
+
+It then byte-compares the checked-in descriptor against the deterministic JSON
+rendering. Hand-editing descriptor fields, changing package identity, changing
+schema hash facts, or introducing absolute paths fails the Graft-local check.
+
+## Test Strategy
+
+Focused contract tests cover:
+
+1. the checked-in descriptor matching the deterministic expected descriptor;
+2. descriptor-only Echo posture and repo-root-relative paths;
+3. stale descriptor drift producing a local check violation.
+
+The script is also wired into `pnpm schema:structural-history:check`, which is
+already part of release checks.
+
+## Non-goals
+
+- Do not change Echo.
+- Do not change Wesley semantics.
+- Do not install a package into Echo.
+- Do not claim Echo-backed storage, replay, or query execution is active.
+- Do not add a real Echo TypeScript client binding in this slice.
+
+## Playback Questions
+
+1. Can a reviewer identify exactly which package Graft expects Echo to host
+   later?
+2. Can a reviewer prove the descriptor came from the schema authority manifest
+   and package identity rather than hand-edited hope?
+3. Can a reviewer see that Echo runtime behavior remains out of scope?

docs/method/backlog/asap/CORE_graft-structural-history-echo-package-descriptor.md

@@ -33,6 +33,9 @@ would Graft hand to Echo?" It should not require Echo to run that package yet.
 ## Design Packet
 
 Primary design packet:
+[`docs/design/CORE_graft-structural-history-echo-package-descriptor.md`](../../../design/CORE_graft-structural-history-echo-package-descriptor.md)
+
+Parent requirements packet:
 [`docs/design/CORE_graft-echo-typescript-integration-requirements.md`](../../../design/CORE_graft-echo-typescript-integration-requirements.md)
 
 Related migration card:

package.json

@@ -46,7 +46,7 @@
     "test:watch": "vitest",
     "lint": "eslint .",
     "typecheck": "tsc --noEmit",
-    "schema:structural-history:check": "tsx scripts/check-structural-history-schema-artifacts.ts",
+    "schema:structural-history:check": "tsx scripts/check-structural-history-schema-artifacts.ts && tsx scripts/check-structural-history-echo-package.ts",
     "pack:check": "pnpm pack --dry-run",
     "guard:agent-worktrees": "tsx scripts/check-agent-worktree-hygiene.ts",
     "security:check": "tsx scripts/check-release-security.ts",

schemas/graft-structural-history.echo-package.json

@@ -0,0 +1,61 @@
+{
+  "descriptorVersion": 1,
+  "package": {
+    "id": "graft.structural-history",
+    "kind": "echo-contract-package",
+    "sourcePackageName": "@flyingrobots/graft",
+    "sourcePackageVersion": "0.8.0"
+  },
+  "schema": {
+    "format": "graphql",
+    "path": "schemas/graft-structural-history.graphql",
+    "sha256": "20c335b4510efbfb5a57a61706bea28a7f82bfc063036b013bd19dc8176905ec",
+    "wesleyL1RegistryHash": "1f0956170eeec399e942fa8e418a4f23bc12ec40bf25f6e1de9510abbb15b832"
+  },
+  "generatedArtifacts": [
+    {
+      "kind": "typescript",
+      "path": "src/generated/graft-structural-history.ts",
+      "sha256": "79737d3c089067685d553f9526c8eb442cb7a20c099a49a771162c2be29559cc",
+      "generator": {
+        "name": "wesley",
+        "version": "0.0.4"
+      }
+    }
+  ],
+  "echo": {
+    "runtimeRequired": false,
+    "packageInstallationRequired": false,
+    "integrationStage": "descriptor-only",
+    "typescriptClientBinding": "planned"
+  },
+  "contracts": {
+    "recordTypes": [
+      "StructuralRepository",
+      "StructuralBasis",
+      "StructuralFileVersion",
+      "StructuralSourceSpan",
+      "StructuralParserRun",
+      "StructuralSymbol",
+      "StructuralSymbolRelation",
+      "StructuralReadingEvidence",
+      "StructuralReading",
+      "GitWarpImportBatch"
+    ],
+    "evidenceLabels": [
+      "ECHO_NATIVE",
+      "GIT_WARP_IMPORTED",
+      "FALLBACK_TRANSLATED"
+    ],
+    "operations": [
+      "queryStructuralRepositoriesOperation",
+      "queryStructuralBasesOperation",
+      "queryStructuralFileVersionsOperation",
+      "queryStructuralSymbolsOperation",
+      "queryStructuralSymbolRelationsOperation",
+      "queryStructuralReadingsOperation",
+      "queryStructuralReadingEvidenceOperation",
+      "queryGitWarpImportBatchesOperation"
+    ]
+  }
+}