diff --git a/src/application/binary/AnalysisSnapshotCache.test.ts b/src/application/binary/AnalysisSnapshotCache.test.ts
index 91b9f8807e..a4025bcca5 100644
--- a/src/application/binary/AnalysisSnapshotCache.test.ts
+++ b/src/application/binary/AnalysisSnapshotCache.test.ts
@@ -1,6 +1,7 @@
 import { describe, expect, it } from "vitest";
 
 import { createAnalysisProfile } from "../../domain/analysisProfile.js";
+import type { RelationshipCoverage } from "../../domain/relationshipCoverage.js";
 import {
   ANALYSIS_SNAPSHOT_PROFILE,
   ANALYSIS_SNAPSHOT_PROVIDER,
@@ -502,57 +503,62 @@ describe("analysis snapshot cache partitioning", () => {
   });
 });
 
-describe("relationship coverage snapshot replay", () => {
-  it("authenticates relationship coverage and replays legacy reads as unknown", () => {
-    const cache = new AnalysisSnapshotCache();
-    const operation = "procedure_callees" as const;
-    const parameters = { procedure: "0x1000", document: "fixture" };
-    const coverage = {
-      status: "complete" as const,
-      diagnostics: ["The provider retained an unresolved call target."],
-    };
-    const execution = createAnalysisExecution(
-      ["0x2000"],
-      ANALYSIS_SNAPSHOT_PROVIDER,
-      {
-        analysisProfile: ANALYSIS_SNAPSHOT_PROFILE,
-        rawResult: ["0x2000"],
-        relationshipCoverage: coverage,
-        subject: {
-          path: ANALYSIS_SNAPSHOT_TARGET.path,
-          sha256: ANALYSIS_SNAPSHOT_TARGET.sha256,
-          format: ANALYSIS_SNAPSHOT_TARGET.format,
-          ...(ANALYSIS_SNAPSHOT_TARGET.architecture === undefined
-            ? {}
-            : { architecture: ANALYSIS_SNAPSHOT_TARGET.architecture }),
-        },
-      },
-    );
-    cache.record({
-      target: ANALYSIS_SNAPSHOT_TARGET,
-      profile: ANALYSIS_SNAPSHOT_PROFILE,
+const createRelationshipCoverageSnapshot = (
+  relationshipCoverage?: RelationshipCoverage,
+) => {
+  const operation = "procedure_callees" as const;
+  const parameters = { procedure: "0x1000", document: "fixture" };
+  const cache = new AnalysisSnapshotCache();
+  const execution = createAnalysisExecution(
+    ["0x2000"],
+    ANALYSIS_SNAPSHOT_PROVIDER,
+    {
+      analysisProfile: ANALYSIS_SNAPSHOT_PROFILE,
+      rawResult: ["0x2000"],
+      subject: ANALYSIS_SNAPSHOT_TARGET,
+      ...(relationshipCoverage === undefined
+        ? {}
+        : { relationshipCoverage }),
+    },
+  );
+  cache.record({
+    target: ANALYSIS_SNAPSHOT_TARGET,
+    profile: ANALYSIS_SNAPSHOT_PROFILE,
+    operation,
+    parameters,
+    execution,
+  });
+  const evidence = createEvidence(
+    ANALYSIS_SNAPSHOT_TARGET,
+    ANALYSIS_SNAPSHOT_PROVIDER,
+    {
       operation,
       parameters,
-      execution,
-    });
-    const evidence = createEvidence(
-      ANALYSIS_SNAPSHOT_TARGET,
-      ANALYSIS_SNAPSHOT_PROVIDER,
-      {
-        operation,
-        parameters,
-        result: ["0x2000"],
-        rawResult: ["0x2000"],
-        analysisProfile: ANALYSIS_SNAPSHOT_PROFILE,
-        relationshipCoverage: coverage,
-      },
-    );
-    const exported = cache.export(
-      ANALYSIS_SNAPSHOT_TARGET,
-      ANALYSIS_SNAPSHOT_PROFILE,
-      createEvidenceBundle([evidence]),
-    );
-    if (!exported.ok) throw exported.error;
+      result: ["0x2000"],
+      rawResult: ["0x2000"],
+      analysisProfile: ANALYSIS_SNAPSHOT_PROFILE,
+      ...(relationshipCoverage === undefined
+        ? {}
+        : { relationshipCoverage }),
+    },
+  );
+  const exported = cache.export(
+    ANALYSIS_SNAPSHOT_TARGET,
+    ANALYSIS_SNAPSHOT_PROFILE,
+    createEvidenceBundle([evidence]),
+  );
+  if (!exported.ok) throw exported.error;
+  return { cache, operation, parameters, snapshot: exported.value };
+};
+
+describe("relationship coverage snapshot replay", () => {
+  it("authenticates coverage and rejects missing serialized fields", () => {
+    const coverage: RelationshipCoverage = {
+      status: "complete",
+      diagnostics: ["The provider retained an unresolved call target."],
+    };
+    const { cache, operation, parameters, snapshot } =
+      createRelationshipCoverageSnapshot(coverage);
     expect(
       cache.lookup(
         ANALYSIS_SNAPSHOT_TARGET,
@@ -562,7 +568,7 @@ describe("relationship coverage snapshot replay", () => {
       )?.relationshipCoverage,
     ).toEqual(coverage);
 
-    const tampered = structuredClone(exported.value);
+    const tampered = structuredClone(snapshot);
     const tamperedEntry = tampered.entries[0];
     if (tamperedEntry === undefined) throw new Error("snapshot entry missing");
     tamperedEntry.execution.relationship_coverage = {
@@ -573,26 +579,34 @@ describe("relationship coverage snapshot replay", () => {
       new AnalysisSnapshotCache().import(tampered, undefined, () => ok(0)).ok,
     ).toBe(false);
 
-    const legacy = structuredClone(exported.value);
-    const legacyEntry = legacy.entries[0];
-    if (legacyEntry === undefined) throw new Error("snapshot entry missing");
-    Reflect.deleteProperty(legacyEntry.execution, "relationship_coverage");
-    const legacyEvidence = createEvidence(
-      ANALYSIS_SNAPSHOT_TARGET,
-      ANALYSIS_SNAPSHOT_PROVIDER,
-      {
-        operation,
-        parameters,
-        result: ["0x2000"],
-        rawResult: ["0x2000"],
-        analysisProfile: ANALYSIS_SNAPSHOT_PROFILE,
-      },
+    const missingCoverage = structuredClone(snapshot);
+    const missingCoverageEntry = missingCoverage.entries[0];
+    if (missingCoverageEntry === undefined)
+      throw new Error("snapshot entry missing");
+    Reflect.deleteProperty(
+      missingCoverageEntry.execution,
+      "relationship_coverage",
     );
-    Reflect.deleteProperty(legacyEvidence, "relationship_coverage");
-    legacy.evidence_bundle = createEvidenceBundle([legacyEvidence]);
-    parseAnalysisSnapshot(legacy);
+    const missingCoverageEvidence = missingCoverage.evidence_bundle.records[0];
+    if (missingCoverageEvidence === undefined)
+      throw new Error("snapshot Evidence missing");
+    Reflect.deleteProperty(missingCoverageEvidence, "relationship_coverage");
+    expect(() => parseAnalysisSnapshot(missingCoverage)).toThrow();
+    expect(
+      new AnalysisSnapshotCache().import(missingCoverage, undefined, () =>
+        ok(0),
+      ).ok,
+    ).toBe(false);
+  });
+
+  it("replays absent coverage as explicitly unknown", () => {
+    const { operation, parameters, snapshot } =
+      createRelationshipCoverageSnapshot();
+    expect(snapshot.entries[0]?.execution.relationship_coverage).toBeNull();
+    expect(snapshot.evidence_bundle.records[0]?.relationship_coverage).toBeNull();
+
     const replayCache = new AnalysisSnapshotCache();
-    expect(replayCache.import(legacy, undefined, () => ok(0)).ok).toBe(true);
+    expect(replayCache.import(snapshot, undefined, () => ok(0)).ok).toBe(true);
     expect(
       replayCache.lookup(
         ANALYSIS_SNAPSHOT_TARGET,
diff --git a/src/contracts/analysisViewApiSurfaceExample.ts b/src/contracts/analysisViewApiSurfaceExample.ts
index 389ac7268d..5879637c2a 100644
--- a/src/contracts/analysisViewApiSurfaceExample.ts
+++ b/src/contracts/analysisViewApiSurfaceExample.ts
@@ -4,7 +4,7 @@ export const API_SURFACE_EXAMPLE = {
     source: {
       kind: "retained-evidence",
       evidence_id:
-        "ev_9e218c18bc6159ec9c8492a9130c286496fb1b6d9f03ec2f4ea3321ce2b15097",
+        "ev_90073e9478eada1e2cc351b523e6ba9231c9b4bc9708773567b880094db9d4c7",
     },
     view: {
       kind: "api-surface",
@@ -14,12 +14,12 @@ export const API_SURFACE_EXAMPLE = {
   },
   output: {
     parent_evidence_id:
-      "ev_9e218c18bc6159ec9c8492a9130c286496fb1b6d9f03ec2f4ea3321ce2b15097",
+      "ev_90073e9478eada1e2cc351b523e6ba9231c9b4bc9708773567b880094db9d4c7",
     parent_operation: "inspect_web_network_capture",
     parent_digest:
-      "9e218c18bc6159ec9c8492a9130c286496fb1b6d9f03ec2f4ea3321ce2b15097",
+      "90073e9478eada1e2cc351b523e6ba9231c9b4bc9708773567b880094db9d4c7",
     view_digest:
-      "47c1859b7a86dd10770061767300bdb6ec177a9254e8dc7863d5ea8603343da6",
+      "c9494341920dc4cff6ecc6d8ed2c5e3abf15976642c253248e220d45f290ca7b",
     artifact: {
       path: "/fixtures/api-surface.har",
       sha256:
diff --git a/src/domain/analysisSnapshot.test.ts b/src/domain/analysisSnapshot.test.ts
index d83ddac306..6ea0a1b5f0 100644
--- a/src/domain/analysisSnapshot.test.ts
+++ b/src/domain/analysisSnapshot.test.ts
@@ -234,6 +234,7 @@ describe("analysis snapshot contract", () => {
               raw_result: null,
               provider: binding.provider,
               limitations: [],
+              relationship_coverage: null,
               locations: [],
               subject: target,
             },
@@ -262,6 +263,7 @@ describe("analysis snapshot contract", () => {
         raw_result: null,
         provider: binding.provider,
         limitations: [],
+        relationship_coverage: null,
         locations: [],
         subject: {
           path: "a\u0000b",
@@ -293,6 +295,7 @@ describe("analysis snapshot contract", () => {
         raw_result: null,
         provider: binding.provider,
         limitations: [],
+        relationship_coverage: null,
         locations: [],
         subject: null,
       },
@@ -456,6 +459,7 @@ describe("analysis snapshot Evidence binding", () => {
         raw_result: rawResult,
         provider: binding.provider,
         limitations: ["fixture limitation"],
+        relationship_coverage: null,
         locations: [{ kind: "address" as const, address: "0x1000" }],
         subject,
       },
@@ -480,11 +484,21 @@ describe("analysis snapshot Evidence binding", () => {
       workflow_entries: [],
       evidence_bundle: createEvidenceBundle([evidence]),
     };
-    const parsedLegacySnapshot = parseAnalysisSnapshot(snapshot);
+    const parsedSnapshot = parseAnalysisSnapshot(snapshot);
     expect(
-      parsedLegacySnapshot.entries[0]?.execution.relationship_coverage,
+      parsedSnapshot.entries[0]?.execution.relationship_coverage,
     ).toBeNull();
 
+    const missingCoverage = structuredClone(snapshot);
+    const missingCoverageEntry = missingCoverage.entries[0];
+    if (missingCoverageEntry === undefined)
+      throw new Error("snapshot entry missing");
+    Reflect.deleteProperty(
+      missingCoverageEntry.execution,
+      "relationship_coverage",
+    );
+    expect(() => parseAnalysisSnapshot(missingCoverage)).toThrow();
+
     expect(() =>
       parseAnalysisSnapshot({
         ...snapshot,
diff --git a/src/domain/analysisSnapshot.ts b/src/domain/analysisSnapshot.ts
index 4e1af5fa8f..e0766ba154 100644
--- a/src/domain/analysisSnapshot.ts
+++ b/src/domain/analysisSnapshot.ts
@@ -145,7 +145,7 @@ const entrySchema = z.object({
     raw_result: jsonValueSchema.nullable(),
     provider: committedProviderSchema,
     limitations: z.array(z.string()),
-    relationship_coverage: relationshipCoverageSchema.nullable().default(null),
+    relationship_coverage: relationshipCoverageSchema.nullable(),
     locations: z.array(evidenceLocationSchema),
     subject: subjectSchema.nullable(),
   }),
@@ -160,7 +160,7 @@ const workflowEntrySchema = z.object({
     provider: committedProviderSchema,
     analysis_profile: analysisProfileSchema,
     limitations: z.array(z.string()),
-    relationship_coverage: relationshipCoverageSchema.nullable().default(null),
+    relationship_coverage: relationshipCoverageSchema.nullable(),
     locations: z.array(evidenceLocationSchema),
     subject: subjectSchema.nullable(),
   }),
@@ -305,9 +305,7 @@ const snapshotContentDigest = (
             format: execution.subject.format,
             architecture: execution.subject.architecture,
           },
-    ...(execution.relationship_coverage === null
-      ? {}
-      : { relationship_coverage: execution.relationship_coverage }),
+    relationship_coverage: execution.relationship_coverage,
   });
   return contentDigest({
     ...metadata,
@@ -872,9 +870,7 @@ const evidenceMatchesWorkflowEntry = (
 const evidenceContentMetadata = (evidence: Evidence) => {
   return {
     limitations: evidence.limitations,
-    ...(evidence.relationship_coverage === null
-      ? {}
-      : { relationship_coverage: evidence.relationship_coverage }),
+    relationship_coverage: evidence.relationship_coverage,
     locations: evidence.locations,
     subject:
       evidence.subject === null
diff --git a/src/domain/evidence.test.ts b/src/domain/evidence.test.ts
index 4b33beb5c0..82ef1dc7b5 100644
--- a/src/domain/evidence.test.ts
+++ b/src/domain/evidence.test.ts
@@ -79,6 +79,21 @@ it("preserves omitted relationship diagnostics and authenticates reported diagno
   ).toThrow("semantic identifier");
 });
 
+it("requires explicit coverage in serialized Evidence while producers encode omission as unknown", () => {
+  const evidence = createEvidence(TARGET, PROVIDER, {
+    operation: "procedure_callees",
+    parameters: { procedure: "0x1000" },
+    result: ["0x2000"],
+  });
+
+  expect(evidence.relationship_coverage).toBeNull();
+  expect(parseEvidence(JSON.parse(JSON.stringify(evidence)))).toEqual(evidence);
+  const oldEnvelope = { ...evidence } as Record<string, unknown>;
+  delete oldEnvelope.relationship_coverage;
+  expect(evidenceSchema.safeParse(oldEnvelope).success).toBe(false);
+  expect(() => parseEvidence(oldEnvelope)).toThrow();
+});
+
 it("projects known provider fields and preserves open JSON payloads", () => {
   const liveProvider = { ...PROVIDER, transient_status: "starting" };
   const evidence = createEvidence(TARGET, liveProvider, {
diff --git a/src/domain/evidence.ts b/src/domain/evidence.ts
index 49cb2a2295..6205c9c135 100644
--- a/src/domain/evidence.ts
+++ b/src/domain/evidence.ts
@@ -135,7 +135,7 @@ const evidenceBaseSchema = z
     authority: evidenceAuthoritySchema,
     environment: executionEnvironmentSchema.nullable(),
     limitations: z.array(z.string()),
-    relationship_coverage: relationshipCoverageSchema.nullable().default(null),
+    relationship_coverage: relationshipCoverageSchema.nullable(),
     locations: z.array(evidenceLocationSchema),
     evidence_links: z.array(prefixedDigestSchema("ev")),
   })
@@ -264,9 +264,7 @@ const semanticProjection = (evidence: EvidenceWithoutId): JsonValue => ({
   authority: evidence.authority,
   environment: evidence.environment,
   limitations: evidence.limitations,
-  ...(evidence.relationship_coverage === null
-    ? {}
-    : { relationship_coverage: evidence.relationship_coverage }),
+  relationship_coverage: evidence.relationship_coverage,
   locations: evidence.locations,
   evidence_links: evidence.evidence_links,
 });
diff --git a/tests/conformance/providers/conformancePackage.test.ts b/tests/conformance/providers/conformancePackage.test.ts
index ebfbb8368b..977fe2521a 100644
--- a/tests/conformance/providers/conformancePackage.test.ts
+++ b/tests/conformance/providers/conformancePackage.test.ts
@@ -5,6 +5,7 @@ import {
   parseConformancePackage,
   type ConformancePackageInput,
 } from "../../../src/domain/conformancePackage.js";
+import { createEvidence } from "../../../src/domain/evidence.js";
 
 const validPackageInput: ConformancePackageInput = {
   name: "test-fixture",
@@ -204,23 +205,19 @@ describe("conformance package construction", () => {
         scenario_id,
         bundle: null,
         required_dimensions: [],
-        envelopes: Array.from({ length: 101 }, (_, index) => ({
-          evidence_id: `ev_${String(index).padStart(64, "0")}`,
-          analysis_profile: null,
-          subject: null,
-          provider: { id: "fixture", name: "Fixture", version: null },
-          predicate_type: "observation",
-          operation: "inspect",
-          parameters: {},
-          raw_result: null,
-          normalized_result: null,
-          confidence: "observed" as const,
-          authority: "shipped-artifact" as const,
-          environment: null,
-          limitations: [],
-          locations: [],
-          evidence_links: [],
-        })),
+        envelopes: Array.from({ length: 101 }, (_, index) =>
+          createEvidence(
+            undefined,
+            { id: "fixture", name: "Fixture", version: null },
+            {
+              operation: "inspect",
+              parameters: { index },
+              result: { index },
+              confidence: "observed",
+              authority: "shipped-artifact",
+            },
+          ),
+        ),
       })),
       verifier_contracts: scenarioIds.map((scenario_id) => ({
         scenario_id,