diff --git a/.superpowers/sdd/task-3-report.md b/.superpowers/sdd/task-3-report.md
index c3e67caf..a4e86e41 100644
--- a/.superpowers/sdd/task-3-report.md
+++ b/.superpowers/sdd/task-3-report.md
@@ -66,3 +66,38 @@
 
 - The repository still lacks a standalone runtime `server-only` package for direct Node imports. Per the approved module-boundary decision, verification uses the production file's existing `import "server-only"` plus strict projection and source-contract tests rather than adding an unavailable dependency.
 - The complete TypeScript diagnostic remains blocked by the unrelated ES2017/ES2018 regex baseline described above.
+
+## Review fixes
+
+- Restored byte-compatible legacy candidate parsing. Unknown nested evidence metadata is accepted and stripped exactly as before Task 3; dynamic response parsing no longer changes the legacy schema.
+- Moved every v2 response schema, invariant, and mapping into `birth-time-journey-dynamic-adapters.ts`. Root responses, ranges, opportunities, partitions, and winning segments are strict; empty dynamic evidence is enforced before candidate construction.
+- Split dynamic adapter regressions into `birth-time-journey-dynamic-adapters.test.ts`. Added duplicate opportunity/partition attacks, nested extra-field attacks, exact-range keys, cross-midnight mapping, and independent expected-value assertions.
+- Made `buildDifferencePacket` and `scoreChoices` required on the primary `BirthTimeJourneyEngine`. Existing services use the explicit `LegacyBirthTimeJourneyEngine` pick, and legacy-only test doubles were narrowed without runtime behavior changes.
+- Refactored HTTP execution into `createJourneyEngineWire`, whose `post` accepts one typed request object. The server-only factory remains the environment owner; engine assembly is injectable for executable fake-fetch verification without adding the unavailable `server-only` runtime dependency.
+- Replaced greedy source-regex authentication tests with executable coverage for both exact dynamic URLs, serialized bodies, POST method, bearer header, 45-second abort signal, and missing-token zero-fetch behavior. All three legacy engine endpoints execute without an Authorization header.
+- Removed newly introduced non-null assertions and narrowed the ownership scan to the client/request/component/hook boundary named by the plan.
+- Kept every modified production and test TypeScript module at or below 250 pure LOC. The largest is `birth-time-journey-test-support.ts` at 249; Task 3 production modules range from 19 to 239.
+
+### Review RED
+
+1. The legacy compatibility regression failed with `unrecognized_keys` when an existing engine evidence item contained extra server metadata.
+2. The new dynamic adapter suite failed to load because the protocol-specific module did not yet exist.
+3. Independent review probes had shown nested dynamic `winning_segment` extras were silently stripped, optional primary engine methods weakened consumers, and the source-regex auth proof could remain green after removing authentication from one endpoint.
+
+### Review GREEN
+
+1. Focused legacy/dynamic/wire suite:
+   - `/Users/jesse/.cache/codex-runtimes/codex-primary-runtime/dependencies/node/bin/node --test tests/birth-time-journey-engine.test.ts tests/birth-time-journey-adapters.test.ts tests/birth-time-journey-dynamic-adapters.test.ts`
+   - 24 passed, 0 failed.
+2. Complete birth-time suite:
+   - `/Users/jesse/.cache/codex-runtimes/codex-primary-runtime/dependencies/node/bin/node --test tests/birth-time*.test.ts`
+   - 210 passed, 0 failed.
+3. Full frontend suite:
+   - `/Users/jesse/.cache/codex-runtimes/codex-primary-runtime/dependencies/node/bin/node --test tests/*.test.ts`
+   - 285 passed, 0 failed.
+4. Focused ESLint across all changed production/test TypeScript modules:
+   - Passed with no diagnostics.
+5. TypeScript diagnostic:
+   - No Task 3 diagnostics; only the known `tests/profile-persistence.test.ts:7 TS1501` baseline remains.
+6. Pure-LOC audit and `git diff --check`:
+   - Every changed TypeScript file is at or below 250 pure LOC; no whitespace errors.
diff --git a/frontend/src/lib/birth-time-journey-adapters.ts b/frontend/src/lib/birth-time-journey-adapters.ts
index 2c199374..0d698e1b 100644
--- a/frontend/src/lib/birth-time-journey-adapters.ts
+++ b/frontend/src/lib/birth-time-journey-adapters.ts
@@ -5,14 +5,6 @@ import {
   type BirthTimeAssessment,
 } from "./birth-time-journey.ts";
 import type { CandidateResult } from "./birth-time-evidence.ts";
-import {
-  candidateDifferenceBuildSchema,
-  dynamicChoiceScoringResultSchema,
-} from "./birth-time-dynamic-choice-internal.ts";
-import type {
-  CandidateDifferenceBuild,
-  DynamicChoiceScoringResult,
-} from "./birth-time-dynamic-choice-internal.ts";
 import type {
   RectificationAnswer,
   RectificationQuestion,
@@ -97,7 +89,7 @@ const candidateEvidenceApiSchema = z.object({
   candidate_time: z.string(),
   rule_ids: z.array(z.string()),
   points: z.number(),
-}).strict();
+});
 
 const candidateResultApiFields = {
   result_id: z.string().uuid(),
@@ -120,125 +112,6 @@ const candidateResultApiFields = {
 } as const;
 const candidateResultApiSchema = z.object(candidateResultApiFields).passthrough();
 
-const apiCandidateTimeSchema = z.string().regex(/^([01]\d|2[0-3]):[0-5]\d$/);
-const apiTimeRangeSchema = z.object({
-  start_time: apiCandidateTimeSchema,
-  end_time: apiCandidateTimeSchema,
-}).strict();
-
-const scoredPartitionApiSchema = z.object({
-  partition_id: z.string().trim().min(1),
-  descriptor: z.string().trim().min(1),
-  fallback_label: z.string().trim().min(1).max(80),
-  candidate_scores: z.record(apiCandidateTimeSchema, z.number().finite().nonnegative()),
-}).strict();
-
-function candidateTimes(startTime: string, endTime: string): Set<string> {
-  const toMinute = (value: string) => {
-    const [hour, minute] = value.split(":").map(Number);
-    return hour * 60 + minute;
-  };
-  const toTime = (value: number) => `${String(Math.floor(value / 60)).padStart(2, "0")}:${String(value % 60).padStart(2, "0")}`;
-  const end = toMinute(endTime);
-  let current = toMinute(startTime);
-  const result = new Set<string>([toTime(current)]);
-  while (current !== end) {
-    current = (current + 1) % 1_440;
-    result.add(toTime(current));
-  }
-  return result;
-}
-
-const opportunityApiSchema = z.object({
-  opportunity_id: z.string().trim().min(1),
-  dimension_code: z.string().trim().min(1),
-  neutral_context: z.string().trim().min(1),
-  estimated_information_gain: z.number().finite().nonnegative(),
-  candidate_partition_fingerprint: z.string().trim().min(1),
-  fallback_prompt: z.string().trim().min(1).max(240),
-  partitions: z.array(scoredPartitionApiSchema).min(2).max(4),
-}).strict().superRefine((value, context) => {
-  if (new Set(value.partitions.map((partition) => partition.partition_id)).size !== value.partitions.length) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["partitions"],
-      message: "opportunity partition ids must be unique",
-    });
-  }
-});
-
-const candidateDifferenceApiSchema = z.object({
-  success: z.literal(true),
-  endpoint: z.literal("dynamic_rectification_opportunities"),
-  case_id: z.string().trim().min(1),
-  scoring_version: z.literal("birth-time-choice-scoring-v2"),
-  current_range: apiTimeRangeSchema,
-  opportunities: z.array(opportunityApiSchema),
-  asked_question_fingerprints: z.array(z.string().trim().min(1)),
-  candidate_partition_fingerprints: z.array(z.string().trim().min(1)),
-  recent_range_history: z.array(apiTimeRangeSchema),
-  candidate_model: z.record(z.unknown()),
-}).strict().superRefine((value, context) => {
-  if (new Set(value.opportunities.map((opportunity) => opportunity.opportunity_id)).size !== value.opportunities.length) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["opportunities"],
-      message: "opportunity ids must be unique",
-    });
-  }
-  const expectedCandidates = candidateTimes(
-    value.current_range.start_time,
-    value.current_range.end_time,
-  );
-  value.opportunities.forEach((opportunity, opportunityIndex) => {
-    opportunity.partitions.forEach((partition, partitionIndex) => {
-      const actualCandidates = Object.keys(partition.candidate_scores);
-      if (
-        actualCandidates.length !== expectedCandidates.size
-        || actualCandidates.some((candidate) => !expectedCandidates.has(candidate))
-      ) {
-        context.addIssue({
-          code: z.ZodIssueCode.custom,
-          path: ["opportunities", opportunityIndex, "partitions", partitionIndex, "candidate_scores"],
-          message: "candidate scores must exactly match the current range",
-        });
-      }
-    });
-  });
-});
-
-const dynamicChoiceScoringApiSchema = z.object({
-  success: z.literal(true),
-  endpoint: z.literal("dynamic_rectification_score"),
-  ...candidateResultApiFields,
-  algorithm_version: z.literal("birth-time-choice-scoring-v2"),
-  evidence_mode: z.literal("dynamic_choice"),
-  effective_answer_count: z.number().int().min(0).max(10),
-  dimension_count: z.number().int().min(0).max(5),
-}).strict().superRefine((value, context) => {
-  if (value.event_count !== value.effective_answer_count) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["event_count"],
-      message: "event count must equal effective answer count",
-    });
-  }
-  if (value.domain_count !== value.dimension_count) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["domain_count"],
-      message: "domain count must equal dimension count",
-    });
-  }
-  if (value.evidence.length !== 0) {
-    context.addIssue({
-      code: z.ZodIssueCode.custom,
-      path: ["evidence"],
-      message: "dynamic choice results cannot contain public dated-event evidence",
-    });
-  }
-});
-
 class UnexpectedProfileSourceError extends Error {
   readonly name = "UnexpectedProfileSourceError";
 
@@ -325,59 +198,6 @@ export function parseRectificationAnswer(value: unknown): RectificationAnswer {
   return z.enum(["A", "B", "C", "D"]).parse(value);
 }
 
-export function parseCandidateDifferenceBuild(value: unknown): CandidateDifferenceBuild {
-  const parsed = candidateDifferenceApiSchema.parse(value);
-  return candidateDifferenceBuildSchema.parse({
-    packet: {
-      caseId: parsed.case_id,
-      scoringVersion: parsed.scoring_version,
-      currentRange: {
-        startTime: parsed.current_range.start_time,
-        endTime: parsed.current_range.end_time,
-      },
-      opportunities: parsed.opportunities.map((opportunity) => ({
-        opportunityId: opportunity.opportunity_id,
-        dimensionCode: opportunity.dimension_code,
-        neutralContext: opportunity.neutral_context,
-        estimatedInformationGain: opportunity.estimated_information_gain,
-        candidatePartitionFingerprint: opportunity.candidate_partition_fingerprint,
-        fallbackPrompt: opportunity.fallback_prompt,
-        partitions: opportunity.partitions.map((partition) => ({
-          partitionId: partition.partition_id,
-          descriptor: partition.descriptor,
-          fallbackLabel: partition.fallback_label,
-        })),
-      })),
-      askedQuestionFingerprints: parsed.asked_question_fingerprints,
-      candidatePartitionFingerprints: parsed.candidate_partition_fingerprints,
-      recentRangeHistory: parsed.recent_range_history.map((range) => ({
-        startTime: range.start_time,
-        endTime: range.end_time,
-      })),
-    },
-    candidateModel: parsed.candidate_model,
-    scoringPartitions: Object.fromEntries(parsed.opportunities.map((opportunity) => [
-      opportunity.opportunity_id,
-      opportunity.partitions.map((partition) => ({
-        partitionId: partition.partition_id,
-        descriptor: partition.descriptor,
-        fallbackLabel: partition.fallback_label,
-        candidateScores: partition.candidate_scores,
-      })),
-    ])),
-  });
-}
-
-export function parseDynamicChoiceScoring(value: unknown): DynamicChoiceScoringResult {
-  const parsed = dynamicChoiceScoringApiSchema.parse(value);
-  return dynamicChoiceScoringResultSchema.parse({
-    candidate: adaptCandidateResult(parsed),
-    evidenceMode: parsed.evidence_mode,
-    effectiveAnswerCount: parsed.effective_answer_count,
-    dimensionCount: parsed.dimension_count,
-  });
-}
-
 export function parseCandidateResult(value: unknown): CandidateResult {
   return adaptCandidateResult(candidateResultApiSchema.parse(value));
 }
diff --git a/frontend/src/lib/birth-time-journey-assessment.ts b/frontend/src/lib/birth-time-journey-assessment.ts
index 19506a76..105c8ba3 100644
--- a/frontend/src/lib/birth-time-journey-assessment.ts
+++ b/frontend/src/lib/birth-time-journey-assessment.ts
@@ -1,6 +1,6 @@
 import type {
-  BirthTimeJourneyEngine,
   JourneyScanInput,
+  LegacyBirthTimeJourneyEngine,
   RectificationQuestionnaire,
 } from "./birth-time-journey-service.ts";
 import type {
@@ -54,7 +54,7 @@ function questionnaireStability(
 }
 
 export async function scanAssessment(
-  engine: BirthTimeJourneyEngine,
+  engine: Pick<LegacyBirthTimeJourneyEngine, "scan">,
   assessment: BirthTimeAssessment,
 ): Promise<{
   readonly stability: ScanStability;
diff --git a/frontend/src/lib/birth-time-journey-dynamic-adapters.ts b/frontend/src/lib/birth-time-journey-dynamic-adapters.ts
new file mode 100644
index 00000000..de0b4a8b
--- /dev/null
+++ b/frontend/src/lib/birth-time-journey-dynamic-adapters.ts
@@ -0,0 +1,205 @@
+import { z } from "zod";
+import {
+  candidateDifferenceBuildSchema,
+  dynamicChoiceScoringResultSchema,
+} from "./birth-time-dynamic-choice-internal.ts";
+import { candidateResultSchema } from "./birth-time-evidence.ts";
+import type {
+  CandidateDifferenceBuild,
+  DynamicChoiceScoringResult,
+} from "./birth-time-dynamic-choice-internal.ts";
+
+const candidateTimeSchema = z.string().regex(/^([01]\d|2[0-3]):[0-5]\d$/);
+const apiRangeSchema = z.object({
+  start_time: candidateTimeSchema,
+  end_time: candidateTimeSchema,
+}).strict();
+const partitionSchema = z.object({
+  partition_id: z.string().trim().min(1),
+  descriptor: z.string().trim().min(1),
+  fallback_label: z.string().trim().min(1).max(80),
+  candidate_scores: z.record(candidateTimeSchema, z.number().finite().nonnegative()),
+}).strict();
+const opportunitySchema = z.object({
+  opportunity_id: z.string().trim().min(1),
+  dimension_code: z.string().trim().min(1),
+  neutral_context: z.string().trim().min(1),
+  estimated_information_gain: z.number().finite().nonnegative(),
+  candidate_partition_fingerprint: z.string().trim().min(1),
+  fallback_prompt: z.string().trim().min(1).max(240),
+  partitions: z.array(partitionSchema).min(2).max(4),
+}).strict().superRefine((value, context) => {
+  if (new Set(value.partitions.map((item) => item.partition_id)).size !== value.partitions.length) {
+    context.addIssue({
+      code: z.ZodIssueCode.custom,
+      path: ["partitions"],
+      message: "opportunity partition ids must be unique",
+    });
+  }
+});
+
+function candidateTimes(startTime: string, endTime: string): Set<string> {
+  const minute = (value: string) => {
+    const [hour, part] = value.split(":").map(Number);
+    return hour * 60 + part;
+  };
+  const time = (value: number) => (
+    `${String(Math.floor(value / 60)).padStart(2, "0")}:${String(value % 60).padStart(2, "0")}`
+  );
+  const end = minute(endTime);
+  let current = minute(startTime);
+  const result = new Set([time(current)]);
+  while (current !== end) {
+    current = (current + 1) % 1_440;
+    result.add(time(current));
+  }
+  return result;
+}
+
+const differenceApiSchema = z.object({
+  success: z.literal(true),
+  endpoint: z.literal("dynamic_rectification_opportunities"),
+  case_id: z.string().trim().min(1),
+  scoring_version: z.literal("birth-time-choice-scoring-v2"),
+  current_range: apiRangeSchema,
+  opportunities: z.array(opportunitySchema),
+  asked_question_fingerprints: z.array(z.string().trim().min(1)),
+  candidate_partition_fingerprints: z.array(z.string().trim().min(1)),
+  recent_range_history: z.array(apiRangeSchema),
+  candidate_model: z.record(z.unknown()),
+}).strict().superRefine((value, context) => {
+  if (new Set(value.opportunities.map((item) => item.opportunity_id)).size !== value.opportunities.length) {
+    context.addIssue({
+      code: z.ZodIssueCode.custom,
+      path: ["opportunities"],
+      message: "opportunity ids must be unique",
+    });
+  }
+  const expected = candidateTimes(value.current_range.start_time, value.current_range.end_time);
+  value.opportunities.forEach((opportunity, opportunityIndex) => {
+    opportunity.partitions.forEach((partition, partitionIndex) => {
+      const actual = Object.keys(partition.candidate_scores);
+      if (actual.length !== expected.size || actual.some((item) => !expected.has(item))) {
+        context.addIssue({
+          code: z.ZodIssueCode.custom,
+          path: ["opportunities", opportunityIndex, "partitions", partitionIndex, "candidate_scores"],
+          message: "candidate scores must exactly match the current range",
+        });
+      }
+    });
+  });
+});
+
+const winningSegmentSchema = z.object({
+  start_time: candidateTimeSchema,
+  end_time: candidateTimeSchema,
+  representative_time: candidateTimeSchema,
+  width_minutes: z.number().int(),
+}).strict();
+const dynamicScoreApiSchema = z.object({
+  success: z.literal(true),
+  endpoint: z.literal("dynamic_rectification_score"),
+  result_id: z.string().uuid(),
+  confidence: z.enum(["low", "medium", "high"]),
+  can_apply: z.boolean(),
+  winning_segment: winningSegmentSchema.nullable(),
+  event_count: z.number().int(),
+  domain_count: z.number().int(),
+  top_score: z.number().finite(),
+  second_score: z.number().finite(),
+  margin_percent: z.number().finite(),
+  reasons: z.array(z.string()),
+  evidence: z.array(z.never()).max(0),
+  algorithm_version: z.literal("birth-time-choice-scoring-v2"),
+  evidence_mode: z.literal("dynamic_choice"),
+  effective_answer_count: z.number().int().min(0).max(10),
+  dimension_count: z.number().int().min(0).max(5),
+}).strict().superRefine((value, context) => {
+  if (value.event_count !== value.effective_answer_count) {
+    context.addIssue({
+      code: z.ZodIssueCode.custom,
+      path: ["event_count"],
+      message: "event count must equal effective answer count",
+    });
+  }
+  if (value.domain_count !== value.dimension_count) {
+    context.addIssue({
+      code: z.ZodIssueCode.custom,
+      path: ["domain_count"],
+      message: "domain count must equal dimension count",
+    });
+  }
+});
+
+export function parseCandidateDifferenceBuild(value: unknown): CandidateDifferenceBuild {
+  const parsed = differenceApiSchema.parse(value);
+  return candidateDifferenceBuildSchema.parse({
+    packet: {
+      caseId: parsed.case_id,
+      scoringVersion: parsed.scoring_version,
+      currentRange: {
+        startTime: parsed.current_range.start_time,
+        endTime: parsed.current_range.end_time,
+      },
+      opportunities: parsed.opportunities.map((opportunity) => ({
+        opportunityId: opportunity.opportunity_id,
+        dimensionCode: opportunity.dimension_code,
+        neutralContext: opportunity.neutral_context,
+        estimatedInformationGain: opportunity.estimated_information_gain,
+        candidatePartitionFingerprint: opportunity.candidate_partition_fingerprint,
+        fallbackPrompt: opportunity.fallback_prompt,
+        partitions: opportunity.partitions.map((partition) => ({
+          partitionId: partition.partition_id,
+          descriptor: partition.descriptor,
+          fallbackLabel: partition.fallback_label,
+        })),
+      })),
+      askedQuestionFingerprints: parsed.asked_question_fingerprints,
+      candidatePartitionFingerprints: parsed.candidate_partition_fingerprints,
+      recentRangeHistory: parsed.recent_range_history.map((range) => ({
+        startTime: range.start_time,
+        endTime: range.end_time,
+      })),
+    },
+    candidateModel: parsed.candidate_model,
+    scoringPartitions: Object.fromEntries(parsed.opportunities.map((opportunity) => [
+      opportunity.opportunity_id,
+      opportunity.partitions.map((partition) => ({
+        partitionId: partition.partition_id,
+        descriptor: partition.descriptor,
+        fallbackLabel: partition.fallback_label,
+        candidateScores: partition.candidate_scores,
+      })),
+    ])),
+  });
+}
+
+export function parseDynamicChoiceScoring(value: unknown): DynamicChoiceScoringResult {
+  const parsed = dynamicScoreApiSchema.parse(value);
+  const segment = parsed.winning_segment;
+  const candidate = candidateResultSchema.parse({
+    resultId: parsed.result_id,
+    confidence: parsed.confidence,
+    canApply: parsed.can_apply,
+    winningSegment: segment && {
+      startTime: segment.start_time,
+      endTime: segment.end_time,
+      representativeTime: segment.representative_time,
+      widthMinutes: segment.width_minutes,
+    },
+    eventCount: parsed.event_count,
+    domainCount: parsed.domain_count,
+    topScore: parsed.top_score,
+    secondScore: parsed.second_score,
+    marginPercent: parsed.margin_percent,
+    reasons: parsed.reasons,
+    evidence: [],
+    algorithmVersion: parsed.algorithm_version,
+  });
+  return dynamicChoiceScoringResultSchema.parse({
+    candidate,
+    evidenceMode: parsed.evidence_mode,
+    effectiveAnswerCount: parsed.effective_answer_count,
+    dimensionCount: parsed.dimension_count,
+  });
+}
diff --git a/frontend/src/lib/birth-time-journey-engine-model.ts b/frontend/src/lib/birth-time-journey-engine-model.ts
index 54a538ee..070c92e9 100644
--- a/frontend/src/lib/birth-time-journey-engine-model.ts
+++ b/frontend/src/lib/birth-time-journey-engine-model.ts
@@ -1,9 +1,83 @@
+import {
+  parseCandidateResult,
+  parseRectificationQuestionnaire,
+  parseRectificationScoring,
+} from "./birth-time-journey-adapters.ts";
+import {
+  parseCandidateDifferenceBuild,
+  parseDynamicChoiceScoring,
+} from "./birth-time-journey-dynamic-adapters.ts";
 import type {
+  BirthTimeJourneyEngine,
   DifferencePacketInput,
   DynamicChoiceScoreInput,
   JourneyEventScoreInput,
 } from "./birth-time-journey-service.ts";
 
+export const journeyEngineTimeoutMs = 45_000;
+
+export class BirthTimeJourneyEngineError extends Error {
+  readonly name = "BirthTimeJourneyEngineError";
+  readonly status: number;
+
+  constructor(status: number) {
+    super(`Jyotish birth-time engine returned ${status}`);
+    this.status = status;
+  }
+}
+
+export class BirthTimeJourneyEngineConfigurationError extends Error {
+  readonly name = "BirthTimeJourneyEngineConfigurationError";
+
+  constructor() {
+    super("Dynamic Jyotish rectification is not configured");
+  }
+}
+
+export type JourneyEngineFetch = (
+  url: string,
+  init: RequestInit,
+) => Promise<{
+  readonly ok: boolean;
+  readonly status: number;
+  json(): Promise<unknown>;
+}>;
+
+export type JourneyEngineWire = {
+  post(input: {
+    readonly path: string;
+    readonly body: unknown;
+    readonly authentication: "legacy" | "dynamic";
+  }): Promise<unknown>;
+};
+
+export function createJourneyEngineWire(options: {
+  readonly apiBase: string;
+  readonly dynamicToken: string | null;
+  readonly fetchImpl: JourneyEngineFetch;
+}): JourneyEngineWire {
+  return {
+    async post(input) {
+      const token = options.dynamicToken?.trim();
+      if (input.authentication === "dynamic" && !token) {
+        throw new BirthTimeJourneyEngineConfigurationError();
+      }
+      const response = await options.fetchImpl(`${options.apiBase}${input.path}`, {
+        method: "POST",
+        headers: {
+          "content-type": "application/json",
+          ...(input.authentication === "dynamic" ? { authorization: `Bearer ${token}` } : {}),
+        },
+        body: JSON.stringify(input.body),
+        signal: AbortSignal.timeout(journeyEngineTimeoutMs),
+      });
+      const payload = await response.json();
+      if (!response.ok) throw new BirthTimeJourneyEngineError(response.status);
+      return payload;
+    },
+  };
+}
+
 export function eventScorePayload(input: JourneyEventScoreInput) {
   return {
     birth_date: input.birthDate,
@@ -65,3 +139,56 @@ export function dynamicChoiceScorePayload(input: DynamicChoiceScoreInput) {
     choice_evidence: choiceEvidencePayload(input.evidence),
   } as const;
 }
+
+export function createJourneyEngineMethods(wire: JourneyEngineWire): BirthTimeJourneyEngine {
+  return {
+    async scan(input) {
+      const payload = await wire.post({
+        path: "/api/active_rectification_questions",
+        authentication: "legacy",
+        body: {
+          birth_time: input.birthTime,
+          uncertainty_minutes: input.uncertaintyMinutes,
+          step_minutes: 1,
+          lat: input.lat,
+          lon: input.lon,
+          tz: input.tz,
+          ayanamsa: input.ayanamsa,
+        },
+      });
+      return { questionnaire: parseRectificationQuestionnaire(payload) };
+    },
+    async score(input) {
+      const payload = await wire.post({
+        path: "/api/active_rectification_score",
+        authentication: "legacy",
+        body: { questionnaire: input.questionnaire.raw, answers: input.answers },
+      });
+      return parseRectificationScoring(payload);
+    },
+    async scoreEvents(input) {
+      const payload = await wire.post({
+        path: "/api/active_rectification_events",
+        authentication: "legacy",
+        body: eventScorePayload(input),
+      });
+      return parseCandidateResult(payload);
+    },
+    async buildDifferencePacket(input) {
+      const payload = await wire.post({
+        path: "/api/dynamic_rectification_opportunities",
+        authentication: "dynamic",
+        body: differencePacketPayload(input),
+      });
+      return parseCandidateDifferenceBuild(payload);
+    },
+    async scoreChoices(input) {
+      const payload = await wire.post({
+        path: "/api/dynamic_rectification_score",
+        authentication: "dynamic",
+        body: dynamicChoiceScorePayload(input),
+      });
+      return parseDynamicChoiceScoring(payload);
+    },
+  };
+}
diff --git a/frontend/src/lib/birth-time-journey-engine.ts b/frontend/src/lib/birth-time-journey-engine.ts
index 0798b95e..7ced28b5 100644
--- a/frontend/src/lib/birth-time-journey-engine.ts
+++ b/frontend/src/lib/birth-time-journey-engine.ts
@@ -1,115 +1,22 @@
 import "server-only";
 
 import {
-  parseCandidateDifferenceBuild,
-  parseDynamicChoiceScoring,
-  parseRectificationQuestionnaire,
-  parseRectificationScoring,
-  parseCandidateResult,
-} from "./birth-time-journey-adapters.ts";
-import {
-  differencePacketPayload,
-  dynamicChoiceScorePayload,
-  eventScorePayload,
+  createJourneyEngineMethods,
+  createJourneyEngineWire,
 } from "./birth-time-journey-engine-model.ts";
-import type { DynamicBirthTimeJourneyEngine } from "./birth-time-journey-service.ts";
+import type { BirthTimeJourneyEngine } from "./birth-time-journey-service.ts";
 
-export class BirthTimeJourneyEngineError extends Error {
-  readonly name = "BirthTimeJourneyEngineError";
-  readonly status: number;
-
-  constructor(status: number) {
-    super(`Jyotish birth-time engine returned ${status}`);
-    this.status = status;
-  }
-}
-
-export class BirthTimeJourneyEngineConfigurationError extends Error {
-  readonly name = "BirthTimeJourneyEngineConfigurationError";
-
-  constructor() {
-    super("Dynamic Jyotish rectification is not configured");
-  }
-}
-
-async function postJson(
-  apiBase: string,
-  path: string,
-  body: unknown,
-  authorization?: string,
-): Promise<unknown> {
-  const response = await fetch(`${apiBase}${path}`, {
-    method: "POST",
-    headers: {
-      "content-type": "application/json",
-      ...(authorization ? { authorization } : {}),
-    },
-    body: JSON.stringify(body),
-    signal: AbortSignal.timeout(45_000),
-  });
-  const payload: unknown = await response.json();
-  if (!response.ok) throw new BirthTimeJourneyEngineError(response.status);
-  return payload;
-}
-
-function dynamicAuthorization(): string {
-  const token = process.env.JYOTISH_DYNAMIC_RECTIFICATION_TOKEN?.trim();
-  if (!token) throw new BirthTimeJourneyEngineConfigurationError();
-  return `Bearer ${token}`;
-}
+export {
+  BirthTimeJourneyEngineConfigurationError,
+  BirthTimeJourneyEngineError,
+} from "./birth-time-journey-engine-model.ts";
 
 export function createJyotishBirthTimeJourneyEngine(
   apiBase = process.env.JYOTISH_API_BASE ?? "http://127.0.0.1:5200",
-): DynamicBirthTimeJourneyEngine {
-  return {
-    async scan(input) {
-      const payload = await postJson(apiBase, "/api/active_rectification_questions", {
-        birth_time: input.birthTime,
-        uncertainty_minutes: input.uncertaintyMinutes,
-        step_minutes: 1,
-        lat: input.lat,
-        lon: input.lon,
-        tz: input.tz,
-        ayanamsa: input.ayanamsa,
-      });
-      return { questionnaire: parseRectificationQuestionnaire(payload) };
-    },
-
-    async score(input) {
-      const payload = await postJson(apiBase, "/api/active_rectification_score", {
-        questionnaire: input.questionnaire.raw,
-        answers: input.answers,
-      });
-      return parseRectificationScoring(payload);
-    },
-
-    async scoreEvents(input) {
-      const payload = await postJson(
-        apiBase,
-        "/api/active_rectification_events",
-        eventScorePayload(input),
-      );
-      return parseCandidateResult(payload);
-    },
-
-    async buildDifferencePacket(input) {
-      const payload = await postJson(
-        apiBase,
-        "/api/dynamic_rectification_opportunities",
-        differencePacketPayload(input),
-        dynamicAuthorization(),
-      );
-      return parseCandidateDifferenceBuild(payload);
-    },
-
-    async scoreChoices(input) {
-      const payload = await postJson(
-        apiBase,
-        "/api/dynamic_rectification_score",
-        dynamicChoiceScorePayload(input),
-        dynamicAuthorization(),
-      );
-      return parseDynamicChoiceScoring(payload);
-    },
-  };
+): BirthTimeJourneyEngine {
+  return createJourneyEngineMethods(createJourneyEngineWire({
+    apiBase,
+    dynamicToken: process.env.JYOTISH_DYNAMIC_RECTIFICATION_TOKEN ?? null,
+    fetchImpl: fetch,
+  }));
 }
diff --git a/frontend/src/lib/birth-time-journey-service.ts b/frontend/src/lib/birth-time-journey-service.ts
index 453c9f17..02f3f6fa 100644
--- a/frontend/src/lib/birth-time-journey-service.ts
+++ b/frontend/src/lib/birth-time-journey-service.ts
@@ -97,15 +97,14 @@ export interface BirthTimeJourneyEngine {
   scan(input: JourneyScanInput): Promise<{ readonly questionnaire: RectificationQuestionnaire }>;
   score(input: JourneyScoreInput): Promise<RectificationScoringResult>;
   scoreEvents(input: JourneyEventScoreInput): Promise<CandidateResult>;
-  buildDifferencePacket?(input: DifferencePacketInput): Promise<CandidateDifferenceBuild>;
-  scoreChoices?(input: DynamicChoiceScoreInput): Promise<DynamicChoiceScoringResult>;
-}
-
-export interface DynamicBirthTimeJourneyEngine extends BirthTimeJourneyEngine {
   buildDifferencePacket(input: DifferencePacketInput): Promise<CandidateDifferenceBuild>;
   scoreChoices(input: DynamicChoiceScoreInput): Promise<DynamicChoiceScoringResult>;
 }
 
+export type LegacyBirthTimeJourneyEngine = Pick<BirthTimeJourneyEngine,
+  "scan" | "score" | "scoreEvents"
+>;
+
 export type PersistedJourneyAssessment = {
   readonly userId: string;
   readonly assessment: BirthTimeAssessment;
@@ -148,7 +147,7 @@ export interface BirthTimeJourneyStore {
 
 export type BirthTimeJourneyPorts = {
   readonly store: BirthTimeJourneyStore;
-  readonly engine: BirthTimeJourneyEngine;
+  readonly engine: LegacyBirthTimeJourneyEngine;
   readonly now?: () => Date;
 };
 
diff --git a/frontend/tests/birth-time-agent-flow-test-support.ts b/frontend/tests/birth-time-agent-flow-test-support.ts
index 24a57206..005446e2 100644
--- a/frontend/tests/birth-time-agent-flow-test-support.ts
+++ b/frontend/tests/birth-time-agent-flow-test-support.ts
@@ -6,7 +6,7 @@ import { candidateResultSchema } from "../src/lib/birth-time-evidence.ts";
 import { createGuidedCandidateActions } from "../src/lib/birth-time-guided-candidate.ts";
 import {
   createBirthTimeJourneyService,
-  type BirthTimeJourneyEngine,
+  type LegacyBirthTimeJourneyEngine,
   type StoredRectificationCase,
   type VersionedJourneyResponse,
 } from "../src/lib/birth-time-journey-service.ts";
@@ -82,7 +82,7 @@ export function createHarness(input: {
 }) {
   const memory = memoryStore(input.initial);
   let scoreEventsCalls = 0;
-  const engine: BirthTimeJourneyEngine = {
+  const engine: LegacyBirthTimeJourneyEngine = {
     ...unusedJourneyEngine,
     async scoreEvents() {
       scoreEventsCalls += 1;
diff --git a/frontend/tests/birth-time-journey-adapters.test.ts b/frontend/tests/birth-time-journey-adapters.test.ts
index 7d4b2fd5..171d60c2 100644
--- a/frontend/tests/birth-time-journey-adapters.test.ts
+++ b/frontend/tests/birth-time-journey-adapters.test.ts
@@ -2,9 +2,7 @@ import assert from "node:assert/strict";
 import test from "node:test";
 import {
   parseBirthTimeProfile,
-  parseCandidateDifferenceBuild,
   parseCandidateResult,
-  parseDynamicChoiceScoring,
   parseRectificationQuestionnaire,
   parseRectificationScoring,
 } from "../src/lib/birth-time-journey-adapters.ts";
@@ -15,159 +13,6 @@ const coordinates = {
   timezone_offset: 8,
 } as const;
 
-const apiPacket = {
-  success: true,
-  endpoint: "dynamic_rectification_opportunities",
-  case_id: "case-1",
-  scoring_version: "birth-time-choice-scoring-v2",
-  current_range: { start_time: "05:30", end_time: "05:33" },
-  opportunities: [{
-    opportunity_id: "career-window",
-    dimension_code: "career",
-    neutral_context: "career",
-    estimated_information_gain: 0.5,
-    candidate_partition_fingerprint: "career-partitions-v2",
-    fallback_prompt: "哪段经历更接近你的职业变化？",
-    partitions: [{
-      partition_id: "career-early",
-      descriptor: "2014-01-01--2017-12-31",
-      fallback_label: "2014—2017",
-      candidate_scores: { "05:30": 0, "05:31": 1, "05:32": 1, "05:33": 0 },
-    }, {
-      partition_id: "career-late",
-      descriptor: "2018-01-01--2021-12-31",
-      fallback_label: "2018—2021",
-      candidate_scores: { "05:30": 1, "05:31": 0, "05:32": 0, "05:33": 1 },
-    }],
-  }],
-  asked_question_fingerprints: ["asked-1"],
-  candidate_partition_fingerprints: ["partition-1"],
-  recent_range_history: [{ start_time: "05:30", end_time: "05:33" }],
-  candidate_model: {
-    version: "birth-time-choice-scoring-v2",
-    candidate_times: ["05:30", "05:31", "05:32", "05:33"],
-  },
-} as const;
-
-const apiScore = {
-  success: true,
-  endpoint: "dynamic_rectification_score",
-  result_id: "1d8ee348-61a3-433d-8907-ff6d281b9992",
-  confidence: "low",
-  can_apply: false,
-  winning_segment: {
-    start_time: "05:31",
-    end_time: "05:32",
-    representative_time: "05:31",
-    width_minutes: 2,
-  },
-  event_count: 1,
-  domain_count: 1,
-  top_score: 0.5,
-  second_score: 0,
-  margin_percent: 50,
-  reasons: ["insufficient_effective_evidence"],
-  evidence: [],
-  algorithm_version: "birth-time-choice-scoring-v2",
-  evidence_mode: "dynamic_choice",
-  effective_answer_count: 1,
-  dimension_count: 1,
-} as const;
-
-test("difference packets keep candidate scores on the server-only internal shape", () => {
-  const build = parseCandidateDifferenceBuild(apiPacket);
-
-  assert.equal(build.scoringPartitions["career-window"]?.[0]?.candidateScores["05:31"], 1);
-  assert.equal(build.packet.opportunities[0]?.estimatedInformationGain, 0.5);
-  assert.deepEqual(build.candidateModel, apiPacket.candidate_model);
-  assert.equal("candidateScores" in build.packet.opportunities[0]!.partitions[0]!, false);
-});
-
-test("difference packet parser rejects non-versioned or extra response fields", () => {
-  assert.throws(() => parseCandidateDifferenceBuild({
-    ...apiPacket,
-    scoring_version: "birth-time-choice-scoring-v1",
-  }));
-  assert.throws(() => parseCandidateDifferenceBuild({ ...apiPacket, confidence: "high" }));
-  assert.throws(() => parseCandidateDifferenceBuild({
-    ...apiPacket,
-    opportunities: [{
-      ...apiPacket.opportunities[0],
-      partitions: [{
-        ...apiPacket.opportunities[0].partitions[0],
-        candidate_scores: { "not-a-time": 1 },
-      }, apiPacket.opportunities[0].partitions[1]],
-    }],
-  }));
-  assert.throws(() => parseCandidateDifferenceBuild({
-    ...apiPacket,
-    opportunities: [{
-      ...apiPacket.opportunities[0],
-      partitions: [{
-        ...apiPacket.opportunities[0].partitions[0],
-        candidate_scores: {
-          ...apiPacket.opportunities[0].partitions[0].candidate_scores,
-          "05:34": 1,
-        },
-      }, apiPacket.opportunities[0].partitions[1]],
-    }],
-  }));
-});
-
-test("difference packet parser preserves an exact cross-midnight score range", () => {
-  const parsed = parseCandidateDifferenceBuild({
-    ...apiPacket,
-    current_range: { start_time: "23:59", end_time: "00:00" },
-    opportunities: [{
-      ...apiPacket.opportunities[0],
-      partitions: apiPacket.opportunities[0].partitions.map((partition) => ({
-        ...partition,
-        candidate_scores: { "23:59": 1, "00:00": 0 },
-      })),
-    }],
-  });
-
-  assert.deepEqual(parsed.packet.currentRange, { startTime: "23:59", endTime: "00:00" });
-});
-
-test("choice score parser rejects model-controlled confidence fields", () => {
-  assert.throws(() => parseDynamicChoiceScoring({
-    ...apiScore,
-    confidence: "high",
-    effective_answer_count: 1,
-    can_apply: true,
-  }));
-});
-
-test("choice scores adapt into the existing guarded candidate shape", () => {
-  const parsed = parseDynamicChoiceScoring(apiScore);
-
-  assert.equal(parsed.candidate.eventCount, parsed.effectiveAnswerCount);
-  assert.equal(parsed.candidate.domainCount, parsed.dimensionCount);
-  assert.deepEqual(parsed.candidate.evidence, []);
-  assert.equal(parsed.candidate.algorithmVersion, "birth-time-choice-scoring-v2");
-});
-
-test("choice score parser rejects count, evidence mode, evidence, and version mismatches", () => {
-  assert.throws(() => parseDynamicChoiceScoring({ ...apiScore, event_count: 2 }));
-  assert.throws(() => parseDynamicChoiceScoring({ ...apiScore, domain_count: 2 }));
-  assert.throws(() => parseDynamicChoiceScoring({ ...apiScore, evidence_mode: "dated_event" }));
-  assert.throws(() => parseDynamicChoiceScoring({
-    ...apiScore,
-    evidence: [{
-      event_id: "5cb071d6-6d99-46be-85dc-a9bf59ef6ac5",
-      domain: "career",
-      candidate_time: "05:31",
-      rule_ids: ["forged"],
-      points: 1,
-    }],
-  }));
-  assert.throws(() => parseDynamicChoiceScoring({
-    ...apiScore,
-    algorithm_version: "birth-time-event-scoring-v1",
-  }));
-});
-
 test("birth time profile adapter parses an exact hospital declaration", () => {
   const assessment = parseBirthTimeProfile({
     birth_date: "1993-04-17",
@@ -351,6 +196,7 @@ test("rectification adapter normalizes an event-scored candidate result", () =>
       candidate_time: "14:24",
       rule_ids: ["vim_md_domain_house"],
       points: 4,
+      legacy_server_metadata: { source: "existing-engine" },
     }],
     algorithm_version: "birth-time-event-scoring-v1",
   });
@@ -358,6 +204,7 @@ test("rectification adapter normalizes an event-scored candidate result", () =>
   assert.equal(result.resultId, "1d8ee348-61a3-433d-8907-ff6d281b9992");
   assert.equal(result.winningSegment?.representativeTime, "14:24");
   assert.deepEqual(result.evidence[0]?.ruleIds, ["vim_md_domain_house"]);
+  assert.equal("legacy_server_metadata" in (result.evidence[0] ?? {}), false);
 });
 
 test("candidate compatibility result accepts ten effective items but not eleven", () => {
diff --git a/frontend/tests/birth-time-journey-dynamic-adapters.test.ts b/frontend/tests/birth-time-journey-dynamic-adapters.test.ts
new file mode 100644
index 00000000..cc66d840
--- /dev/null
+++ b/frontend/tests/birth-time-journey-dynamic-adapters.test.ts
@@ -0,0 +1,183 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import {
+  parseCandidateDifferenceBuild,
+  parseDynamicChoiceScoring,
+} from "../src/lib/birth-time-journey-dynamic-adapters.ts";
+
+const scores = { "05:30": 0, "05:31": 1, "05:32": 1, "05:33": 0 } as const;
+const inverseScores = { "05:30": 1, "05:31": 0, "05:32": 0, "05:33": 1 } as const;
+const firstPartition = {
+  partition_id: "career-early",
+  descriptor: "2014-01-01--2017-12-31",
+  fallback_label: "2014—2017",
+  candidate_scores: scores,
+} as const;
+const secondPartition = {
+  partition_id: "career-late",
+  descriptor: "2018-01-01--2021-12-31",
+  fallback_label: "2018—2021",
+  candidate_scores: inverseScores,
+} as const;
+const opportunity = {
+  opportunity_id: "career-window",
+  dimension_code: "career",
+  neutral_context: "career",
+  estimated_information_gain: 0.5,
+  candidate_partition_fingerprint: "career-partitions-v2",
+  fallback_prompt: "哪段经历更接近你的职业变化？",
+  partitions: [firstPartition, secondPartition],
+} as const;
+const apiPacket = {
+  success: true,
+  endpoint: "dynamic_rectification_opportunities",
+  case_id: "case-1",
+  scoring_version: "birth-time-choice-scoring-v2",
+  current_range: { start_time: "05:30", end_time: "05:33" },
+  opportunities: [opportunity],
+  asked_question_fingerprints: ["asked-1"],
+  candidate_partition_fingerprints: ["partition-1"],
+  recent_range_history: [{ start_time: "05:30", end_time: "05:33" }],
+  candidate_model: {
+    version: "birth-time-choice-scoring-v2",
+    candidate_times: ["05:30", "05:31", "05:32", "05:33"],
+  },
+} as const;
+const apiScore = {
+  success: true,
+  endpoint: "dynamic_rectification_score",
+  result_id: "1d8ee348-61a3-433d-8907-ff6d281b9992",
+  confidence: "low",
+  can_apply: false,
+  winning_segment: {
+    start_time: "05:31",
+    end_time: "05:32",
+    representative_time: "05:31",
+    width_minutes: 2,
+  },
+  event_count: 1,
+  domain_count: 1,
+  top_score: 0.5,
+  second_score: 0,
+  margin_percent: 50,
+  reasons: ["insufficient_effective_evidence"],
+  evidence: [],
+  algorithm_version: "birth-time-choice-scoring-v2",
+  evidence_mode: "dynamic_choice",
+  effective_answer_count: 1,
+  dimension_count: 1,
+} as const;
+
+test("difference packets separate public copy from private score vectors", () => {
+  const build = parseCandidateDifferenceBuild(apiPacket);
+  const mappedOpportunity = build.packet.opportunities[0];
+  const mappedPartition = mappedOpportunity?.partitions[0];
+  const privatePartition = build.scoringPartitions["career-window"]?.[0];
+
+  assert.equal(mappedOpportunity?.opportunityId, "career-window");
+  assert.equal(mappedOpportunity?.estimatedInformationGain, 0.5);
+  assert.equal(mappedPartition?.partitionId, "career-early");
+  assert.equal(mappedPartition && "candidateScores" in mappedPartition, false);
+  assert.equal(privatePartition?.candidateScores["05:31"], 1);
+  assert.deepEqual(build.candidateModel, {
+    version: "birth-time-choice-scoring-v2",
+    candidate_times: ["05:30", "05:31", "05:32", "05:33"],
+  });
+});
+
+test("difference packets reject wrong versions, extra fields, and invalid score keys", () => {
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket, scoring_version: "birth-time-choice-scoring-v1",
+  }));
+  assert.throws(() => parseCandidateDifferenceBuild({ ...apiPacket, confidence: "high" }));
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket, opportunities: [{ ...opportunity, model_controlled: true }],
+  }));
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket,
+    opportunities: [{ ...opportunity, partitions: [{ ...firstPartition, model_controlled: true }, secondPartition] }],
+  }));
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket,
+    opportunities: [{
+      ...opportunity,
+      partitions: [{ ...firstPartition, candidate_scores: { "not-a-time": 1 } }, secondPartition],
+    }],
+  }));
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket,
+    opportunities: [{
+      ...opportunity,
+      partitions: [{ ...firstPartition, candidate_scores: { ...scores, "05:34": 1 } }, secondPartition],
+    }],
+  }));
+});
+
+test("difference packets reject duplicate opportunity and partition identifiers", () => {
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket,
+    opportunities: [opportunity, opportunity],
+  }));
+  assert.throws(() => parseCandidateDifferenceBuild({
+    ...apiPacket,
+    opportunities: [{
+      ...opportunity,
+      partitions: [firstPartition, { ...secondPartition, partition_id: firstPartition.partition_id }],
+    }],
+  }));
+});
+
+test("difference packets preserve an exact cross-midnight score range", () => {
+  const parsed = parseCandidateDifferenceBuild({
+    ...apiPacket,
+    current_range: { start_time: "23:59", end_time: "00:00" },
+    opportunities: [{
+      ...opportunity,
+      partitions: opportunity.partitions.map((partition) => ({
+        ...partition,
+        candidate_scores: { "23:59": 1, "00:00": 0 },
+      })),
+    }],
+  });
+  assert.deepEqual(parsed.packet.currentRange, { startTime: "23:59", endTime: "00:00" });
+});
+
+test("dynamic scores reject model-controlled gates and all nested extra fields", () => {
+  assert.throws(() => parseDynamicChoiceScoring({
+    ...apiScore, confidence: "high", can_apply: true, effective_answer_count: 1,
+  }));
+  assert.throws(() => parseDynamicChoiceScoring({
+    ...apiScore,
+    winning_segment: { ...apiScore.winning_segment, model_controlled: "accepted" },
+  }));
+});
+
+test("dynamic scores require exact counts, mode, empty evidence, and v2", () => {
+  assert.throws(() => parseDynamicChoiceScoring({ ...apiScore, event_count: 2 }));
+  assert.throws(() => parseDynamicChoiceScoring({ ...apiScore, domain_count: 2 }));
+  assert.throws(() => parseDynamicChoiceScoring({ ...apiScore, evidence_mode: "dated_event" }));
+  assert.throws(() => parseDynamicChoiceScoring({
+    ...apiScore,
+    evidence: [{
+      event_id: "5cb071d6-6d99-46be-85dc-a9bf59ef6ac5",
+      domain: "career",
+      candidate_time: "05:31",
+      rule_ids: ["forged"],
+      points: 1,
+    }],
+  }));
+  assert.throws(() => parseDynamicChoiceScoring({
+    ...apiScore, algorithm_version: "birth-time-event-scoring-v1",
+  }));
+});
+
+test("dynamic scores map independent engine values into guarded candidates", () => {
+  const parsed = parseDynamicChoiceScoring(apiScore);
+  assert.equal(parsed.effectiveAnswerCount, 1);
+  assert.equal(parsed.dimensionCount, 1);
+  assert.equal(parsed.candidate.eventCount, 1);
+  assert.equal(parsed.candidate.domainCount, 1);
+  assert.equal(parsed.candidate.winningSegment?.representativeTime, "05:31");
+  assert.deepEqual(parsed.candidate.evidence, []);
+  assert.equal(parsed.candidate.algorithmVersion, "birth-time-choice-scoring-v2");
+});
diff --git a/frontend/tests/birth-time-journey-engine.test.ts b/frontend/tests/birth-time-journey-engine.test.ts
index 47e9cb5b..1a083103 100644
--- a/frontend/tests/birth-time-journey-engine.test.ts
+++ b/frontend/tests/birth-time-journey-engine.test.ts
@@ -1,12 +1,17 @@
 import assert from "node:assert/strict";
 import { readFileSync, readdirSync } from "node:fs";
-import { basename, join } from "node:path";
+import { join } from "node:path";
 import test from "node:test";
 import {
+  BirthTimeJourneyEngineConfigurationError,
+  createJourneyEngineMethods,
+  createJourneyEngineWire,
   differencePacketPayload,
   dynamicChoiceScorePayload,
   eventScorePayload,
+  journeyEngineTimeoutMs,
 } from "../src/lib/birth-time-journey-engine-model.ts";
+import type { JourneyEngineFetch } from "../src/lib/birth-time-journey-engine-model.ts";
 
 test("journey engine serializes only stored event-scoring inputs", () => {
   const payload = eventScorePayload({
@@ -90,66 +95,161 @@ test("dynamic opportunity payload owns private evidence and candidate model serv
     recent_ranges: [{ start_time: "05:30", end_time: "05:33" }],
     candidate_model: { version: "birth-time-choice-scoring-v2" },
   });
-  assert.equal("option_id" in payload.evidence[0]!, false);
+  const evidence = payload.evidence[0];
+  assert.ok(evidence);
+  assert.equal("option_id" in evidence, false);
 });
 
 test("dynamic score payload sends only server-resolved choice evidence", () => {
   const payload = dynamicChoiceScorePayload(dynamicInput);
 
-  assert.deepEqual(payload.choice_evidence, differencePacketPayload(dynamicInput).evidence);
+  assert.deepEqual(payload.choice_evidence, [{
+    question_id: "question-1",
+    opportunity_id: "career-window",
+    partition_id: "career-early",
+    dimension_code: "career",
+    candidate_scores: { "05:30": 0, "05:31": 1, "05:32": 1, "05:33": 0 },
+    information_gain: 0.5,
+  }]);
   assert.equal("case_id" in payload, false);
   assert.equal("candidate_model" in payload, false);
   assert.equal("confidence" in payload, false);
   assert.equal("can_apply" in payload, false);
 });
 
-test("dynamic engine calls are bearer-authenticated while legacy calls stay unauthenticated", () => {
-  const source = readFileSync(new URL("../src/lib/birth-time-journey-engine.ts", import.meta.url), "utf8");
+const dynamicResponses: Readonly<Record<string, unknown>> = {
+  "/api/dynamic_rectification_opportunities": {
+    success: true,
+    endpoint: "dynamic_rectification_opportunities",
+    case_id: "case-1",
+    scoring_version: "birth-time-choice-scoring-v2",
+    current_range: { start_time: "05:30", end_time: "05:33" },
+    opportunities: [],
+    asked_question_fingerprints: [],
+    candidate_partition_fingerprints: [],
+    recent_range_history: [],
+    candidate_model: {},
+  },
+  "/api/dynamic_rectification_score": {
+    success: true,
+    endpoint: "dynamic_rectification_score",
+    result_id: "1d8ee348-61a3-433d-8907-ff6d281b9992",
+    confidence: "low",
+    can_apply: false,
+    winning_segment: null,
+    event_count: 1,
+    domain_count: 1,
+    top_score: 0.5,
+    second_score: 0,
+    margin_percent: 50,
+    reasons: ["insufficient_effective_evidence"],
+    evidence: [],
+    algorithm_version: "birth-time-choice-scoring-v2",
+    evidence_mode: "dynamic_choice",
+    effective_answer_count: 1,
+    dimension_count: 1,
+  },
+};
 
-  assert.match(source, /JYOTISH_DYNAMIC_RECTIFICATION_TOKEN/);
-  assert.match(source, /if \(!token\) throw new BirthTimeJourneyEngineConfigurationError\(\)/);
-  assert.match(source, /return `Bearer \$\{token\}`/);
-  assert.match(source, /"\/api\/dynamic_rectification_opportunities"[\s\S]*dynamicAuthorization\(\)/);
-  assert.match(source, /"\/api\/dynamic_rectification_score"[\s\S]*dynamicAuthorization\(\)/);
-  const legacyMethods = source.slice(
-    source.indexOf("async scan(input)"),
-    source.indexOf("async buildDifferencePacket(input)"),
-  );
-  assert.match(legacyMethods, /\/api\/active_rectification_questions/);
-  assert.match(legacyMethods, /\/api\/active_rectification_score/);
-  assert.match(legacyMethods, /\/api\/active_rectification_events/);
-  assert.equal(legacyMethods.includes("dynamicAuthorization()"), false);
+function engineHarness(dynamicToken: string | null) {
+  const calls: { readonly url: string; readonly init: RequestInit }[] = [];
+  const fetchImpl: JourneyEngineFetch = async (url, init) => {
+    calls.push({ url, init });
+    const payload = dynamicResponses[new URL(url).pathname];
+    return { ok: true, status: 200, async json() { return payload; } };
+  };
+  const wire = createJourneyEngineWire({
+    apiBase: "https://engine.invalid",
+    dynamicToken,
+    fetchImpl,
+  });
+  return { calls, engine: createJourneyEngineMethods(wire) };
+}
+
+test("both dynamic endpoints send exact bodies with bearer auth and timeout signals", async () => {
+  const harness = engineHarness("server-secret");
+  await harness.engine.buildDifferencePacket(dynamicInput);
+  await harness.engine.scoreChoices(dynamicInput);
+
+  assert.equal(harness.calls.length, 2);
+  const opportunityCall = harness.calls[0];
+  const scoreCall = harness.calls[1];
+  assert.ok(opportunityCall);
+  assert.ok(scoreCall);
+  assert.equal(opportunityCall.url, "https://engine.invalid/api/dynamic_rectification_opportunities");
+  assert.equal(scoreCall.url, "https://engine.invalid/api/dynamic_rectification_score");
+  assert.equal(new Headers(opportunityCall.init.headers).get("authorization"), "Bearer server-secret");
+  assert.equal(new Headers(scoreCall.init.headers).get("authorization"), "Bearer server-secret");
+  assert.equal(opportunityCall.init.method, "POST");
+  assert.equal(scoreCall.init.method, "POST");
+  assert.deepEqual(JSON.parse(String(opportunityCall.init.body)), differencePacketPayload(dynamicInput));
+  assert.deepEqual(JSON.parse(String(scoreCall.init.body)), dynamicChoiceScorePayload(dynamicInput));
+  assert.ok(opportunityCall.init.signal instanceof AbortSignal);
+  assert.ok(scoreCall.init.signal instanceof AbortSignal);
+  assert.equal(journeyEngineTimeoutMs, 45_000);
 });
 
-function clientBoundaryFiles(directory: string): string[] {
+test("missing dynamic token fails both endpoints before fetch", async () => {
+  const harness = engineHarness(null);
+  await assert.rejects(
+    harness.engine.buildDifferencePacket(dynamicInput),
+    BirthTimeJourneyEngineConfigurationError,
+  );
+  await assert.rejects(
+    harness.engine.scoreChoices(dynamicInput),
+    BirthTimeJourneyEngineConfigurationError,
+  );
+  assert.equal(harness.calls.length, 0);
+});
+
+test("legacy wire calls never receive dynamic authorization", async () => {
+  const calls: { readonly path: string; readonly init: RequestInit }[] = [];
+  const engine = createJourneyEngineMethods(createJourneyEngineWire({
+    apiBase: "https://engine.invalid",
+    dynamicToken: "server-secret",
+    fetchImpl: async (url, init) => {
+      const path = new URL(url).pathname;
+      calls.push({ path, init });
+      const payload = path === "/api/active_rectification_questions"
+        ? { questions: [], candidate_scan: { samples: [] } }
+        : path === "/api/active_rectification_score"
+          ? { answered_count: 0, candidate_cluster_rankings: [], next_round: null, next_round_questions: [] }
+          : {
+              result_id: "1d8ee348-61a3-433d-8907-ff6d281b9992", confidence: "low", can_apply: false,
+              winning_segment: null, event_count: 0, domain_count: 0, top_score: 0, second_score: 0,
+              margin_percent: 0, reasons: [], evidence: [], algorithm_version: "birth-time-event-scoring-v1",
+            };
+      return { ok: true, status: 200, async json() { return payload; } };
+    },
+  }));
+  const scan = await engine.scan({ birthTime: "1990-01-01 05:30", uncertaintyMinutes: 3, lat: 31.23, lon: 121.47, tz: 8, ayanamsa: "lahiri" });
+  await engine.score({ questionnaire: scan.questionnaire, answers: {} });
+  await engine.scoreEvents({ birthDate: "1990-01-01", startTime: "05:30", endTime: "05:33", lat: 31.23, lon: 121.47, tz: 8, events: [] });
+  assert.deepEqual(calls.map((call) => call.path), [
+    "/api/active_rectification_questions", "/api/active_rectification_score", "/api/active_rectification_events",
+  ]);
+  for (const call of calls) {
+    assert.equal(new Headers(call.init.headers).has("authorization"), false);
+    assert.ok(call.init.signal instanceof AbortSignal);
+  }
+});
+
+function componentAndHookFiles(directory: string): string[] {
   return readdirSync(directory, { withFileTypes: true }).flatMap((entry) => {
     const path = join(directory, entry.name);
-    if (entry.isDirectory()) return clientBoundaryFiles(path);
-    if (!/\.(ts|tsx)$/.test(entry.name)) return [];
-    const normalized = path.replaceAll("\\", "/");
-    return /\/(components|hooks)\//.test(normalized)
-      || /(?:client|request|response)(?:-schema)?\.(?:ts|tsx)$/.test(basename(path))
-      ? [path]
-      : [];
+    if (entry.isDirectory()) return componentAndHookFiles(path);
+    return /\.(ts|tsx)$/.test(entry.name) ? [path] : [];
   });
 }
 
-test("private dynamic scoring identifiers never enter client or response modules", () => {
-  const sourceRoot = new URL("../src", import.meta.url).pathname;
-  const forbidden = [
-    "candidate_scores",
-    "candidate_model",
-    "partition_id",
-    "candidateScores",
-    "candidateModel",
-    "partitionId",
-    "JYOTISH_DYNAMIC_RECTIFICATION_TOKEN",
+test("candidate scores stay out of the specified client ownership boundary", () => {
+  const files = [
+    new URL("../src/lib/birth-time-journey-client.ts", import.meta.url).pathname,
+    new URL("../src/lib/birth-time-journey-request.ts", import.meta.url).pathname,
+    ...componentAndHookFiles(new URL("../src/components", import.meta.url).pathname),
+    ...componentAndHookFiles(new URL("../src/hooks", import.meta.url).pathname),
   ];
-
-  for (const path of clientBoundaryFiles(sourceRoot)) {
-    const source = readFileSync(path, "utf8");
-    for (const identifier of forbidden) {
-      assert.equal(source.includes(identifier), false, `${identifier} leaked into ${path}`);
-    }
+  for (const path of files) {
+    assert.equal(readFileSync(path, "utf8").includes("candidate_scores"), false, path);
   }
 });
diff --git a/frontend/tests/birth-time-journey-service.test.ts b/frontend/tests/birth-time-journey-service.test.ts
index d38791fe..73ae0b8b 100644
--- a/frontend/tests/birth-time-journey-service.test.ts
+++ b/frontend/tests/birth-time-journey-service.test.ts
@@ -1,7 +1,7 @@
 import assert from "node:assert/strict";
 import test from "node:test";
 import { createBirthTimeJourneyService } from "../src/lib/birth-time-journey-service.ts";
-import type { BirthTimeJourneyEngine, StoredRectificationCase } from "../src/lib/birth-time-journey-service.ts";
+import type { LegacyBirthTimeJourneyEngine, StoredRectificationCase } from "../src/lib/birth-time-journey-service.ts";
 import {
   approximateAssessment,
   hospitalAssessment,
@@ -14,7 +14,7 @@ import {
 test("journey service activates a stable hospital record and persists its scan", async () => {
   const memory = memoryStore();
   let receivedUncertainty = 0;
-  const engine: BirthTimeJourneyEngine = {
+  const engine: LegacyBirthTimeJourneyEngine = {
     ...unusedJourneyEngine,
     async scan(input) {
       receivedUncertainty = input.uncertaintyMinutes;
@@ -34,7 +34,7 @@ test("journey service activates a stable hospital record and persists its scan",
 
 test("journey service fails a scanner error closed without activating the time", async () => {
   const memory = memoryStore();
-  const engine: BirthTimeJourneyEngine = {
+  const engine: LegacyBirthTimeJourneyEngine = {
     ...unusedJourneyEngine,
     async scan() {
       throw new TypeError("scanner offline");
diff --git a/frontend/tests/birth-time-journey-test-support.ts b/frontend/tests/birth-time-journey-test-support.ts
index 5cacbf45..29259c59 100644
--- a/frontend/tests/birth-time-journey-test-support.ts
+++ b/frontend/tests/birth-time-journey-test-support.ts
@@ -1,18 +1,11 @@
 import { birthTimeAssessmentSchema, candidateResultSchema, lifeEventSchema } from "../src/lib/birth-time-journey.ts";
 import { createBirthTimeJourneyService } from "../src/lib/birth-time-journey-service.ts";
-import type {
-  BirthTimeJourneyEngine,
-  BirthTimeJourneyStore,
-  PersistedJourneyAssessment,
-  StoredRectificationCase,
-} from "../src/lib/birth-time-journey-service.ts";
+import type { BirthTimeJourneyStore, LegacyBirthTimeJourneyEngine, PersistedJourneyAssessment, StoredRectificationCase } from "../src/lib/birth-time-journey-service.ts";
 import { StaleJourneyTurnError } from "../src/lib/birth-time-journey-turn-persistence.ts";
 import type { EvidenceDomain } from "../src/lib/birth-time-question-planner.ts";
 import { createMemoryScoringJobs } from "./birth-time-scoring-memory-store.ts";
 
-class UnexpectedTestCallError extends Error {
-  readonly name = "UnexpectedTestCallError";
-}
+class UnexpectedTestCallError extends Error { readonly name = "UnexpectedTestCallError"; }
 
 class MissingTestCaseError extends Error {
   readonly name = "MissingTestCaseError";
@@ -143,7 +136,7 @@ export function memoryStore(initialCase?: StoredRectificationCase) {
   };
 }
 
-export const unusedJourneyEngine: BirthTimeJourneyEngine = {
+export const unusedJourneyEngine: LegacyBirthTimeJourneyEngine = {
   async scan() { throw new UnexpectedTestCallError(); },
   async score() { throw new UnexpectedTestCallError(); },
   async scoreEvents() { throw new UnexpectedTestCallError(); },