diff --git a/.changeset/environment-artifact-checksum-coverage-describe.md b/.changeset/environment-artifact-checksum-coverage-describe.md
new file mode 100644
index 0000000000..24aa57019f
--- /dev/null
+++ b/.changeset/environment-artifact-checksum-coverage-describe.md
@@ -0,0 +1,10 @@
+---
+"@objectstack/spec": patch
+---
+
+The environment artifact's `checksum` now states its own coverage boundary, and `grantedPermissions` states that it sits outside the digest by design.
+
+Describe text only — no key, value schema or accept-set change on `EnvironmentArtifactSchema`, and the digest itself is computed and verified by the control plane, not here.
+
+- **`checksum`** carried the shared `Sha256DigestSchema` describe ("SHA-256 digest (64 hex chars)"), which says what the value *is* and nothing about what it *covers*. It now has its own field-level describe: the SHA-256 digest of the canonical JSON serialization of the `metadata` block (stable key ordering), computed by the control plane when assembling the GET response — and coverage stops there, so no other key on the envelope is under the digest. The shared `Sha256DigestSchema` describe is unchanged, so every other digest field still inherits it.
+- **`grantedPermissions`** gains one sentence group at the end of its describe: it sits beside `metadata`, outside the digest, and integrity of the granted consent set rests on the carrier — the artifact is environment-local and control-plane served (ADR-0003 / cloud ADR-0007) — an accepted boundary of this envelope rather than an oversight. Its five existing clauses (the manifest-`id` keying, the `sys_package_installation` source, the enforcer consumer, absent ≠ `{}`) are unchanged.
diff --git a/packages/spec/src/system/environment-artifact.test.ts b/packages/spec/src/system/environment-artifact.test.ts
index bac79afd93..d395a8ec6f 100644
--- a/packages/spec/src/system/environment-artifact.test.ts
+++ b/packages/spec/src/system/environment-artifact.test.ts
@@ -205,6 +205,47 @@ describe('EnvironmentArtifactSchema (wire shape)', () => {
     });
   });
 
+  // ─── Digest coverage is stated on the surface, not only in a docblock ────
+  //
+  // There is no digest MECHANISM here to pin: `checksum` is computed by the
+  // control plane and this envelope only carries it. What can silently rot is
+  // the sentence that states what the digest covers — and the shape that
+  // carries it. `checksum` used to inherit the SHARED `Sha256DigestSchema`
+  // describe, which says what the value IS and nothing about what it COVERS;
+  // the coverage sentence therefore belongs on the KEY, and putting it back on
+  // the shared schema would relabel every other digest field in the repo.
+  describe('the checksum describe states its coverage boundary, on the key and not on the shared digest', () => {
+    const checksumDescription = () => EnvironmentArtifactSchema.shape.checksum.description ?? '';
+
+    it('names the `metadata` block as what the digest covers', () => {
+      expect(checksumDescription()).toMatch(/canonical JSON serialization of the `metadata` block/);
+    });
+
+    it('states what it does NOT cover — nothing else on the envelope, `grantedPermissions` included', () => {
+      expect(checksumDescription()).toMatch(/nothing else on the envelope/);
+      expect(checksumDescription()).toMatch(/`grantedPermissions` included/);
+    });
+
+    it('leaves the SHARED Sha256DigestSchema describe untouched — the key-level text did not leak onto it', () => {
+      expect(Sha256DigestSchema.description).toBe('SHA-256 digest (64 hex chars)');
+      expect(EnvironmentArtifactSchema.shape.checksum).not.toBe(Sha256DigestSchema);
+    });
+
+    it('validates exactly as the shared digest still does — describing the key changed no rule', () => {
+      expect(EnvironmentArtifactSchema.shape.checksum.safeParse(WIRE_CHECKSUM).success).toBe(true);
+      expect(EnvironmentArtifactSchema.shape.checksum.safeParse(WIRE_CHECKSUM.toUpperCase()).success).toBe(false);
+      expect(EnvironmentArtifactSchema.shape.checksum.safeParse(WIRE_CHECKSUM.slice(0, 63)).success).toBe(false);
+    });
+
+    // `check:doc-authoring`: describe prose projects into
+    // content/docs/references/** and the generated skill artifacts, where an
+    // internal issue id is a citation-shaped token resolving to nothing. The
+    // card anchor lives in a `//` comment beside the key instead.
+    it('carries no internal issue id — this text is read by customers', () => {
+      expect(checksumDescription()).not.toMatch(/#\d{3,}/);
+    });
+  });
+
   // The v0 keys are tombstoned, not silently stripped: authoring one raises
   // the prescription itself (retiredKey, #3855), and `tsc` types the key
   // `never` at the authoring site.
@@ -383,6 +424,16 @@ describe('grantedPermissions — install-time granted set per plugin manifest `i
       expect(description).toMatch(/`\{\}` = consent-bearing and consented to nothing/);
     });
 
+    it('the key description also states the digest boundary and where integrity of the granted set rests', () => {
+      const description = EnvironmentArtifactSchema.shape.grantedPermissions.description ?? '';
+      expect(description).toMatch(/outside the `checksum` digest/);
+      expect(description).toMatch(/covers the `metadata` block/);
+      expect(description).toMatch(/rests on the carrier/);
+      expect(description).toMatch(/ADR-0003 \/ cloud ADR-0007/);
+      // Same `check:doc-authoring` rule as the checksum pin above.
+      expect(description).not.toMatch(/#\d{3,}/);
+    });
+
     it('any string key parses — which IS the residual risk: a `package_id`-shaped key is accepted and would simply never be looked up', () => {
       const parsed = EnvironmentArtifactSchema.parse({
         ...wireMinimal,
diff --git a/packages/spec/src/system/environment-artifact.zod.ts b/packages/spec/src/system/environment-artifact.zod.ts
index 09ce094cf1..cea5caa47d 100644
--- a/packages/spec/src/system/environment-artifact.zod.ts
+++ b/packages/spec/src/system/environment-artifact.zod.ts
@@ -109,7 +109,12 @@ export const EnvironmentArtifactSchema = lazySchema(() => z.object({
    * a type change invisible to key-level gates, #4666; pinned by the
    * parse tests next to this file).
    */
-  checksum: Sha256DigestSchema,
+  checksum: Sha256DigestSchema.describe(
+    'SHA-256 digest of the canonical JSON serialization of the `metadata` block (stable key '
+    + 'ordering), computed by the control plane when assembling the GET response. Coverage stops '
+    + 'at that block: nothing else on the envelope — `grantedPermissions` included — is under '
+    + 'this digest, so a matching checksum attests the compiled metadata and nothing more.',
+  ),
 
   /** Build timestamp (ISO 8601). */
   builtAt: z.string().datetime().optional(),
@@ -170,13 +175,19 @@ export const EnvironmentArtifactSchema = lazySchema(() => z.object({
    * silently. Sits beside `metadata`, outside the `checksum` digest (which
    * covers the `metadata` block only).
    */
+  // Internal anchor for the digest-coverage boundary stated in the describe below: it was
+  // recorded as accepted on the premise that the carrier is trusted end-to-end (#14993).
   grantedPermissions: z.record(z.string(), PluginPermissionsSchema).optional()
     .describe(
       'Install-time GRANTED permission set per plugin, keyed by the plugin manifest `id` '
       + '(not the control-plane `package_id`). Written by the cloud control plane at consent-compile '
       + 'time from `sys_package_installation.granted_permissions`; consumed by the materialize-time '
       + 'loader via `PluginPermissionEnforcer.registerGrantedPermissions`. Absent = no consent record; '
-      + '`{}` = consent-bearing and consented to nothing — the two are never collapsed.',
+      + '`{}` = consent-bearing and consented to nothing — the two are never collapsed. '
+      + 'Sits beside `metadata`, outside the `checksum` digest, which covers the `metadata` block '
+      + 'only: integrity of the granted set rests on the carrier — the artifact is '
+      + 'environment-local and control-plane served (ADR-0003 / cloud ADR-0007) — an accepted '
+      + 'boundary of this envelope, not an oversight.',
     ),
 
   // ── Retired v0 keys (#4740, ADR-0049) ──────────────────────────────