diff --git a/packages/agent/src/index.ts b/packages/agent/src/index.ts
index a55dbc8..abea692 100644
--- a/packages/agent/src/index.ts
+++ b/packages/agent/src/index.ts
@@ -84,6 +84,7 @@ export async function main(): Promise<void> {
 
   const app = createApp({
     mathEngine,
+    rag,
     workflow: {
       rag,
       mathEngine,
diff --git a/packages/agent/src/server/app.ts b/packages/agent/src/server/app.ts
index e60c631..faf24f2 100644
--- a/packages/agent/src/server/app.ts
+++ b/packages/agent/src/server/app.ts
@@ -4,12 +4,15 @@ import { Hono } from "hono";
 import { cors } from "hono/cors";
 
 import type { MathEngineClient } from "../tools/math-engine-client.js";
+import type { RagClient } from "../tools/rag-client.js";
 import type { RunOptions, VerificationWorkflowDeps } from "../workflows/verification-workflow.js";
 import { createGenerateRoute } from "./routes/generate.js";
 import { createHealthRoute } from "./routes/health.js";
+import { createSourceProblemsRoute } from "./routes/source-problems.js";
 
 export interface AppDeps {
   mathEngine: MathEngineClient;
+  rag: RagClient;
   workflow: VerificationWorkflowDeps;
   workflowOptions?: RunOptions;
 }
@@ -27,6 +30,7 @@ export function createApp(deps: AppDeps): Hono {
   );
 
   app.route("/", createHealthRoute(deps.mathEngine));
+  app.route("/", createSourceProblemsRoute(deps.rag));
   app.route("/", createGenerateRoute(deps.workflow, deps.workflowOptions));
 
   return app;
diff --git a/packages/agent/src/server/routes/source-problems.ts b/packages/agent/src/server/routes/source-problems.ts
new file mode 100644
index 0000000..62f8080
--- /dev/null
+++ b/packages/agent/src/server/routes/source-problems.ts
@@ -0,0 +1,81 @@
+/**
+ * GET /api/source-problems — read-only corpus lookup.
+ *
+ * Reuses the in-memory RagClient (D-7) without LLM / generation. The web S3
+ * problem picker calls this to browse SourceProblem rows by school/grade/topic.
+ *
+ * Figure-dependent rows are dropped: the corpus image path is a non-servable
+ * AI-Hub scan, so a statement that points at a figure/graph/table is unusable
+ * as text-only. See isFigureDependent for why there is no clean corpus flag.
+ */
+
+import { zValidator } from "@hono/zod-validator";
+import { Hono } from "hono";
+import { z } from "zod";
+
+import {
+  DifficultySchema,
+  SchoolLevelSchema,
+} from "../../schemas/source-problem.schema.js";
+import type { RagClient } from "../../tools/rag-client.js";
+
+// Big k = scan whole topic (≥ largest ~1.8k rows). search() already sorts the full
+// match set so this only widens the final slice; lets figure filtering fill `limit`
+// on figure-heavy topics instead of returning an all-figure first-50.
+const FIGURE_FILTER_POOL = 2000;
+
+// No reliable corpus flag for "needs a figure": media.image is on 100% of rows, and
+// the VISUAL taxonomy tag also marks self-contained solids ("직육면체의 겉넓이"). So match
+// only explicit references — "그림", a shown graph/도형/표 via deictic phrases, or embedded
+// <table>. Bare "그래프"/"도형"/"표"/"좌표" stay (e.g. "y=x²의 그래프의 꼭짓점" is self-contained).
+const FIGURE_REFERENCE =
+  /그림|그래프와\s*같|(?:다음|아래|위)\s*그래프|(?:다음|아래)\s*도형|(?:다음|아래|위)의?\s*표(?:는|를|에|\s)|<table/i;
+
+export function isFigureDependent(questionText: string): boolean {
+  return FIGURE_REFERENCE.test(questionText);
+}
+
+const GradeQueryParamSchema = z.preprocess(
+  (value) => {
+    if (value === "common" || value === "null" || value === "") return null;
+    if (value === "1" || value === 1) return 1;
+    if (value === "2" || value === 2) return 2;
+    if (value === "3" || value === 3) return 3;
+    return value;
+  },
+  z.union([z.literal(1), z.literal(2), z.literal(3)]).nullable(),
+);
+
+const SourceProblemsQuerySchema = z.object({
+  school_level: SchoolLevelSchema,
+  grade: GradeQueryParamSchema,
+  topic_code: z.string().min(1).optional(),
+  difficulty: DifficultySchema.optional(),
+  limit: z.coerce.number().int().min(1).max(50).default(30),
+});
+
+export function createSourceProblemsRoute(rag: RagClient): Hono {
+  const app = new Hono();
+
+  app.get(
+    "/api/source-problems",
+    zValidator("query", SourceProblemsQuerySchema),
+    async (c) => {
+      const q = c.req.valid("query");
+      const results = await rag.search({
+        school_level: q.school_level,
+        grade: q.grade ?? null,
+        topic_code: q.topic_code,
+        difficulty: q.difficulty,
+        k: FIGURE_FILTER_POOL,
+      });
+      const problems = results
+        .map((r) => r.problem)
+        .filter((p) => !isFigureDependent(p.question_text))
+        .slice(0, q.limit);
+      return c.json(problems);
+    },
+  );
+
+  return app;
+}
diff --git a/packages/agent/tests/source-problems-route.test.ts b/packages/agent/tests/source-problems-route.test.ts
new file mode 100644
index 0000000..7e542be
--- /dev/null
+++ b/packages/agent/tests/source-problems-route.test.ts
@@ -0,0 +1,185 @@
+import { Hono } from "hono";
+import { describe, expect, it } from "vitest";
+
+import type {
+  RagQuery,
+  RagResult,
+  SourceProblem,
+} from "../src/schemas/index.js";
+import {
+  createSourceProblemsRoute,
+  isFigureDependent,
+} from "../src/server/routes/source-problems.js";
+import type { RagClient } from "../src/tools/rag-client.js";
+
+function makeProblem(overrides: {
+  item_id: string;
+  difficulty_norm: SourceProblem["difficulty_norm"];
+  topic_code?: SourceProblem["topic_code"];
+  school_level?: SourceProblem["school_level"];
+  grade?: SourceProblem["grade"];
+  question_text?: string;
+}): SourceProblem {
+  return {
+    item_id: overrides.item_id,
+    source_dataset: "111",
+    split: "train",
+    source_label_type: "problem_label",
+    school_level: overrides.school_level ?? "middle",
+    grade: overrides.grade ?? 3,
+    semester: null,
+    topic_code: overrides.topic_code ?? "9수02-09",
+    topic_name: "이차방정식",
+    achievement_standard: "이차방정식을 풀 수 있다.",
+    question_text: overrides.question_text ?? `질문 ${overrides.item_id}`,
+    answer_text: `정답 ${overrides.item_id}`,
+    explanation_text: null,
+    choice_blocks: null,
+    problem_type_norm: "short_answer",
+    difficulty_norm: overrides.difficulty_norm,
+    question_image_relpath: null,
+    answer_image_relpath: null,
+    question_json_relpath: null,
+    answer_json_relpath: null,
+  };
+}
+
+function createMockRag(problems: SourceProblem[]): RagClient {
+  return {
+    async search(query: RagQuery): Promise<RagResult[]> {
+      const filtered = problems.filter((problem) => {
+        if (problem.school_level !== query.school_level) return false;
+        if (query.grade !== null && problem.grade !== query.grade) return false;
+        if (query.topic_code && problem.topic_code !== query.topic_code) {
+          return false;
+        }
+        if (query.difficulty && problem.difficulty_norm !== query.difficulty) {
+          return false;
+        }
+        return true;
+      });
+
+      return filtered.slice(0, query.k ?? 8).map((problem) => ({
+        item_id: problem.item_id,
+        similarity: 0.5,
+        problem,
+        match_reason: "structural",
+      }));
+    },
+  };
+}
+
+describe("GET /api/source-problems", () => {
+  const fixtures: SourceProblem[] = [
+    makeProblem({ item_id: "mock-1", difficulty_norm: "easy" }),
+    makeProblem({ item_id: "mock-2", difficulty_norm: "medium" }),
+    makeProblem({ item_id: "mock-3", difficulty_norm: "hard" }),
+    makeProblem({ item_id: "mock-4", difficulty_norm: "hard" }),
+    makeProblem({
+      item_id: "mock-other-topic",
+      difficulty_norm: "medium",
+      topic_code: "9수02-08",
+    }),
+    makeProblem({
+      item_id: "mock-other-grade",
+      difficulty_norm: "easy",
+      grade: 2,
+    }),
+    makeProblem({
+      item_id: "mock-figure",
+      difficulty_norm: "medium",
+      question_text: "다음 그림과 같이 정육면체를 잘라 낸 입체도형에서 면의 개수를 구하여라.",
+    }),
+  ];
+
+  function buildApp(): Hono {
+    const app = new Hono();
+    app.route("/", createSourceProblemsRoute(createMockRag(fixtures)));
+    return app;
+  }
+
+  it("returns source problems filtered by school_level + grade + topic_code", async () => {
+    const app = buildApp();
+    const topic = encodeURIComponent("9수02-09");
+    const res = await app.request(
+      `/api/source-problems?school_level=middle&grade=3&topic_code=${topic}`,
+    );
+
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as SourceProblem[];
+    expect(Array.isArray(body)).toBe(true);
+    expect(body).toHaveLength(4);
+    for (const item of body) {
+      expect(item).toHaveProperty("item_id");
+      expect(item).toHaveProperty("question_text");
+      expect(item).toHaveProperty("answer_text");
+      expect(item).toHaveProperty("difficulty_norm");
+      expect(item.topic_code).toBe("9수02-09");
+      expect(item.school_level).toBe("middle");
+      expect(item.grade).toBe(3);
+    }
+  });
+
+  it("returns 400 when school_level is missing", async () => {
+    const app = buildApp();
+    const res = await app.request("/api/source-problems?grade=3");
+    expect(res.status).toBe(400);
+  });
+
+  it("narrows results when difficulty=hard", async () => {
+    const app = buildApp();
+    const topic = encodeURIComponent("9수02-09");
+    const res = await app.request(
+      `/api/source-problems?school_level=middle&grade=3&topic_code=${topic}&difficulty=hard`,
+    );
+
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as SourceProblem[];
+    expect(body).toHaveLength(2);
+    expect(body.every((problem) => problem.difficulty_norm === "hard")).toBe(true);
+  });
+
+  it("returns [] for an unknown topic_code", async () => {
+    const app = buildApp();
+    const topic = encodeURIComponent("9수99-99");
+    const res = await app.request(
+      `/api/source-problems?school_level=middle&grade=3&topic_code=${topic}`,
+    );
+
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as SourceProblem[];
+    expect(body).toEqual([]);
+  });
+
+  it("excludes figure-dependent problems (statement references 그림)", async () => {
+    const app = buildApp();
+    const topic = encodeURIComponent("9수02-09");
+    const res = await app.request(
+      `/api/source-problems?school_level=middle&grade=3&topic_code=${topic}`,
+    );
+
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as SourceProblem[];
+    expect(body.some((p) => p.item_id === "mock-figure")).toBe(false);
+    expect(body.every((p) => !p.question_text.includes("그림"))).toBe(true);
+  });
+});
+
+describe("isFigureDependent", () => {
+  it.each([
+    ["다음 그림과 같이 정육면체를 잘라 낸 입체도형에서", true],
+    ["다음 그래프는 x초 후 높이 y를 나타낸 것이다.", true],
+    ["아래 그래프는 시간과 거리의 관계를 나타낸 것이다.", true],
+    ["걸린 시간과 이동 거리를 그래프와 같이 나타내면", true],
+    ["다음 표는 어느 반의 도수분포표이다.", true],
+    ["다음 도형의 둘레의 길이를 구하여라.", true],
+    ["성적을 정리하면 <table border> 와 같다.", true],
+    ["모든 모서리의 합이 48이고 대각선이 3√6인 직육면체의 겉넓이를 구하시오.", false],
+    ["이차함수 y=2x^2+3x-2의 그래프와 x축의 교점의 x좌표를 구하시오.", false],
+    ["수직선 위에서 -7/5보다 큰 가장 작은 정수를 구하시오.", false],
+    ["a^3+b^3을 보기와 같이 변형하여 값을 구하시오.", false],
+    ["이차방정식 (2x+1)(x-4)=0을 풀어라.", false],
+  ])("%s -> %s", (text, expected) => {
+    expect(isFigureDependent(text)).toBe(expected);
+  });
+});
diff --git a/packages/web/__tests__/latex-renderer.test.ts b/packages/web/__tests__/latex-renderer.test.ts
new file mode 100644
index 0000000..f540d3f
--- /dev/null
+++ b/packages/web/__tests__/latex-renderer.test.ts
@@ -0,0 +1,128 @@
+import { describe, expect, it } from "vitest";
+import {
+  splitDelimited,
+  type Segment,
+} from "../components/math/latex-renderer";
+
+/*
+ * splitDelimited — char-by-char scanner.
+ *
+ * Dispatch order: \$ (escape) → $$ → $ → \[ → \( → text.
+ * Unmatched openers mirror behavior of unmatched `$`: dump the rest into the
+ * trailing text buffer (one merged text segment).
+ *
+ * Baseline probed against the current implementation (cases 5, 11):
+ *   - splitDelimited("")     === []
+ *   - splitDelimited("a $b") === [{ kind: "text", value: "a $b" }]
+ *
+ * The new `\[` / `\(` branches must mirror that exact shape on unmatched
+ * close — see case 11.
+ */
+
+describe("splitDelimited", () => {
+  it("case 1: $x$ → one inline 'x'", () => {
+    const expected: Segment[] = [{ kind: "inline", latex: "x" }];
+    expect(splitDelimited("$x$")).toEqual(expected);
+  });
+
+  it("case 2: $$x$$ → one block 'x'", () => {
+    const expected: Segment[] = [{ kind: "block", latex: "x" }];
+    expect(splitDelimited("$$x$$")).toEqual(expected);
+  });
+
+  it("case 3: \\$5 → text '$5' (escape preserved)", () => {
+    const expected: Segment[] = [{ kind: "text", value: "$5" }];
+    expect(splitDelimited("\\$5")).toEqual(expected);
+  });
+
+  it("case 4: foo → text 'foo'", () => {
+    const expected: Segment[] = [{ kind: "text", value: "foo" }];
+    expect(splitDelimited("foo")).toEqual(expected);
+  });
+
+  it("case 5: empty string → [] (baseline behavior)", () => {
+    const expected: Segment[] = [];
+    expect(splitDelimited("")).toEqual(expected);
+  });
+
+  it("case 6: \\[ x = 1 \\] → one block ' x = 1 '", () => {
+    const expected: Segment[] = [{ kind: "block", latex: " x = 1 " }];
+    expect(splitDelimited("\\[ x = 1 \\]")).toEqual(expected);
+  });
+
+  it("case 7: \\( x \\) → one inline ' x '", () => {
+    const expected: Segment[] = [{ kind: "inline", latex: " x " }];
+    expect(splitDelimited("\\( x \\)")).toEqual(expected);
+  });
+
+  it("case 8: array env inside \\[ ... \\] — row-break '\\\\' preserved", () => {
+    // Source: \[ \begin{array}{l}a\\b\end{array} \]
+    // Expected block latex: " \begin{array}{l}a\\b\end{array} "
+    const expected: Segment[] = [
+      { kind: "block", latex: " \\begin{array}{l}a\\\\b\\end{array} " },
+    ];
+    expect(
+      splitDelimited("\\[ \\begin{array}{l}a\\\\b\\end{array} \\]"),
+    ).toEqual(expected);
+  });
+
+  it("case 9: $a$ and \\[ b \\] → inline 'a' + text ' and ' + block ' b '", () => {
+    const expected: Segment[] = [
+      { kind: "inline", latex: "a" },
+      { kind: "text", value: " and " },
+      { kind: "block", latex: " b " },
+    ];
+    expect(splitDelimited("$a$ and \\[ b \\]")).toEqual(expected);
+  });
+
+  it("case 10: \\( x \\) and \\[ y \\] → inline ' x ' + text ' and ' + block ' y '", () => {
+    const expected: Segment[] = [
+      { kind: "inline", latex: " x " },
+      { kind: "text", value: " and " },
+      { kind: "block", latex: " y " },
+    ];
+    expect(splitDelimited("\\( x \\) and \\[ y \\]")).toEqual(expected);
+  });
+
+  it("case 11: unmatched \\[ → mirror $-unmatched (one merged text segment)", () => {
+    // Source: "hello \[ x = 1"
+    // Baseline for $-unmatched ("a $b"): [{ kind: "text", value: "a $b" }]
+    // → New \[-unmatched must produce ONE text segment containing entire string.
+    const expected: Segment[] = [{ kind: "text", value: "hello \\[ x = 1" }];
+    expect(splitDelimited("hello \\[ x = 1")).toEqual(expected);
+  });
+
+  it("case 12: \\[ \\text{ 두 복소수 } z_1 \\] → one block with Korean \\text intact", () => {
+    const expected: Segment[] = [
+      { kind: "block", latex: " \\text{ 두 복소수 } z_1 " },
+    ];
+    expect(splitDelimited("\\[ \\text{ 두 복소수 } z_1 \\]")).toEqual(expected);
+  });
+
+  it("case 13: stray \\] → text '\\] stray' (no opener, plain text)", () => {
+    const expected: Segment[] = [{ kind: "text", value: "\\] stray" }];
+    expect(splitDelimited("\\] stray")).toEqual(expected);
+  });
+
+  it("case 14: \\[ a \\\\ b \\] → one block ' a \\\\ b ' (row-break does not close)", () => {
+    // Source chars: \[ ' a ' \\ ' b ' \]
+    // The \\ at positions 5-6 must not be mistaken for \].
+    const expected: Segment[] = [{ kind: "block", latex: " a \\\\ b " }];
+    expect(splitDelimited("\\[ a \\\\ b \\]")).toEqual(expected);
+  });
+
+  it("case 15: \\[ a \\( b \\) c \\] → outer block consumes inner verbatim", () => {
+    const expected: Segment[] = [
+      { kind: "block", latex: " a \\( b \\) c " },
+    ];
+    expect(splitDelimited("\\[ a \\( b \\) c \\]")).toEqual(expected);
+  });
+
+  it("case 16: \\$ \\[ x \\] → text '$ ' + block ' x ' (escape + new delim coexist)", () => {
+    const expected: Segment[] = [
+      { kind: "text", value: "$ " },
+      { kind: "block", latex: " x " },
+    ];
+    expect(splitDelimited("\\$ \\[ x \\]")).toEqual(expected);
+  });
+});
diff --git a/packages/web/__tests__/verification-storage-key.test.ts b/packages/web/__tests__/verification-storage-key.test.ts
new file mode 100644
index 0000000..6859eca
--- /dev/null
+++ b/packages/web/__tests__/verification-storage-key.test.ts
@@ -0,0 +1,84 @@
+import { describe, expect, it } from "vitest";
+import { verificationStorageKey } from "../lib/verification-storage-key";
+
+describe("verificationStorageKey", () => {
+  it("joins fields with | for middle grade 3 with sourceItemId", () => {
+    expect(
+      verificationStorageKey({
+        grade: 3,
+        schoolLevel: "middle",
+        topic: "9수02-09",
+        topicName: "이차방정식",
+        mode: "structural",
+        sourceItemId: "item-abc-123",
+      }),
+    ).toBe(
+      "openmath:verification-result|3|middle|9수02-09|이차방정식|structural|item-abc-123",
+    );
+  });
+
+  it("renders null grade as empty slot (Array.prototype.join semantics)", () => {
+    expect(
+      verificationStorageKey({
+        grade: null,
+        schoolLevel: "high",
+        topic: "10공수01-04",
+        topicName: "복소수와 이차방정식",
+        mode: "conceptual",
+        sourceItemId: "high-1",
+      }),
+    ).toBe(
+      "openmath:verification-result||high|10공수01-04|복소수와 이차방정식|conceptual|high-1",
+    );
+  });
+
+  it("produces the same key for the same inputs (deterministic)", () => {
+    const args = {
+      grade: 1 as const,
+      schoolLevel: "middle" as const,
+      topic: "9수02-03",
+      topicName: "일차방정식",
+      mode: "structural" as const,
+      sourceItemId: "x",
+    };
+    expect(verificationStorageKey(args)).toBe(verificationStorageKey(args));
+  });
+
+  it("differs when sourceItemId changes (writer vs reader consistency)", () => {
+    const base = {
+      grade: 2 as const,
+      schoolLevel: "middle" as const,
+      topic: "9수02-07",
+      topicName: "연립일차방정식",
+      mode: "structural" as const,
+    };
+    expect(
+      verificationStorageKey({ ...base, sourceItemId: "a" }),
+    ).not.toBe(verificationStorageKey({ ...base, sourceItemId: "b" }));
+  });
+
+  it("differs when mode toggles structural ↔ conceptual", () => {
+    const base = {
+      grade: 3 as const,
+      schoolLevel: "middle" as const,
+      topic: "9수03-04",
+      topicName: "이차함수와 그래프",
+      sourceItemId: "x-1",
+    };
+    expect(
+      verificationStorageKey({ ...base, mode: "structural" }),
+    ).not.toBe(verificationStorageKey({ ...base, mode: "conceptual" }));
+  });
+
+  it("starts with the openmath:verification-result namespace prefix", () => {
+    const key = verificationStorageKey({
+      grade: 1,
+      schoolLevel: "middle",
+      topic: "9수01-01",
+      topicName: "소인수분해",
+      mode: "structural",
+      sourceItemId: "src-1",
+    });
+    expect(key.startsWith("openmath:verification-result|")).toBe(true);
+  });
+});
diff --git a/packages/web/app/app/new/export/page.tsx b/packages/web/app/app/new/export/page.tsx
index df737ca..54770ea 100644
--- a/packages/web/app/app/new/export/page.tsx
+++ b/packages/web/app/app/new/export/page.tsx
@@ -14,9 +14,8 @@ type Props = {
     school?: string | string[];
     topic?: string | string[];
     mode?: string | string[];
-    dims?: string | string[];
+    srcRef?: string | string[];
     adopted?: string | string[];
-    source?: string | string[];
   };
 };
 
@@ -40,13 +39,12 @@ export default function ExportPage({ searchParams }: Props) {
   const grade = parseGrade(searchParams.grade);
   const topic = findTopic(pickFirst(searchParams.topic));
   const mode = parseMode(pickFirst(searchParams.mode));
-  const dims = parseList(pickFirst(searchParams.dims));
+  const srcRef = pickFirst(searchParams.srcRef) ?? "";
   const adoptedIds = parseList(pickFirst(searchParams.adopted));
-  const sourceProblemText = pickFirst(searchParams.source) ?? "";
 
   let problems: ResultProblem[] = [];
   if (topic !== null && mode !== null) {
-    const all = generateMockResults(topic, mode, dims);
+    const all = generateMockResults(topic, mode);
     problems = all.filter((p) => adoptedIds.includes(p.id));
   }
 
@@ -56,8 +54,7 @@ export default function ExportPage({ searchParams }: Props) {
       schoolLevel={schoolLevel}
       topic={topic}
       mode={mode}
-      dims={dims}
-      sourceProblemText={sourceProblemText}
+      sourceItemId={srcRef}
       adoptedIds={adoptedIds}
       problems={problems}
     />
diff --git a/packages/web/app/app/new/export/view.tsx b/packages/web/app/app/new/export/view.tsx
index 6ec8037..e6d3760 100644
--- a/packages/web/app/app/new/export/view.tsx
+++ b/packages/web/app/app/new/export/view.tsx
@@ -4,6 +4,7 @@ import Link from "next/link";
 import { useEffect, useMemo, useRef, useState } from "react";
 import { LatexRenderer } from "@/components/math/latex-renderer";
 import { type Grade, type SchoolLevel, type Topic, gradeLabel } from "../topic/data";
+import { verificationStorageKey } from "@/lib/verification-storage-key";
 import type { ResultProblem } from "../result/mock";
 
 function buildDefaultTitle(
@@ -20,8 +21,7 @@ type Props = {
   grade: Grade | null;
   topic: Topic | null;
   mode: "structural" | "conceptual" | null;
-  dims: string[];
-  sourceProblemText: string;
+  sourceItemId: string;
   adoptedIds: string[];
   problems: ResultProblem[];
 };
@@ -57,33 +57,12 @@ function shuffleArray<T>(arr: readonly T[]): T[] {
   return out;
 }
 
-function storageKey(
-  schoolLevel: SchoolLevel,
-  grade: Grade | null,
-  topic: Topic,
-  mode: "structural" | "conceptual",
-  dims: string[],
-  sourceProblemText: string,
-): string {
-  return [
-    "openmath:verification-result",
-    grade,
-    schoolLevel,
-    topic.code,
-    topic.name,
-    mode,
-    [...dims].sort().join(","),
-    sourceProblemText,
-  ].join("|");
-}
-
 function resultHref(
   schoolLevel: SchoolLevel,
   grade: Grade | null,
   topic: Topic,
   mode: "structural" | "conceptual" | null,
-  dims: readonly string[],
-  sourceProblemText: string,
+  sourceItemId: string,
 ): string {
   const params = new URLSearchParams({
     grade: grade === null ? "common" : String(grade),
@@ -91,8 +70,7 @@ function resultHref(
     topic: topic.code,
   });
   if (mode !== null) params.set("mode", mode);
-  if (dims.length > 0) params.set("dims", [...dims].join(","));
-  if (sourceProblemText.length > 0) params.set("source", sourceProblemText);
+  if (sourceItemId.length > 0) params.set("srcRef", sourceItemId);
   return `/app/new/result?${params.toString()}`;
 }
 
@@ -117,9 +95,8 @@ function parseStoredProblem(raw: unknown): StoredProblem | null {
   };
 }
 
-function toResultProblem(problem: StoredProblem, index: number, dims: string[]): ResultProblem {
+function toResultProblem(problem: StoredProblem, index: number): ResultProblem {
   const status = problem.verification_status === "partial" ? "warn" : problem.verification_status;
-  const missingDims = dims.filter((dim) => !problem.preserved_dimensions.includes(dim));
   return {
     id: problem.id,
     number: index + 1,
@@ -128,8 +105,6 @@ function toResultProblem(problem: StoredProblem, index: number, dims: string[]):
     questionLatex: problem.question_latex,
     answerLatex: problem.answer_latex,
     solutionLatex: problem.explanation_latex ?? "검증 파이프라인에서 생성된 문항입니다.",
-    preservedDims: problem.preserved_dimensions,
-    missingDims: status === "warn" ? missingDims : [],
     failReason: status === "fail" ? "검증 실패 — 채택할 수 없습니다." : null,
   };
 }
@@ -188,8 +163,7 @@ export function ExportView({
   grade,
   topic,
   mode,
-  dims,
-  sourceProblemText,
+  sourceItemId,
   adoptedIds,
   problems,
 }: Props) {
@@ -212,21 +186,37 @@ export function ExportView({
   useEffect(() => {
     setDisplayProblems(problems);
     if ((schoolLevel === "middle" && grade === null) || topic === null || mode === null) return;
+    if (sourceItemId === "") return;
+    let raw: string | null = null;
     try {
-      const raw = window.sessionStorage.getItem(
-        storageKey(schoolLevel, grade, topic, mode, dims, sourceProblemText),
+      raw = window.sessionStorage.getItem(
+        verificationStorageKey({
+          grade,
+          schoolLevel,
+          topic: topic.code,
+          topicName: topic.name,
+          mode,
+          sourceItemId,
+        }),
       );
-      if (raw === null) return;
-      const parsed: unknown = JSON.parse(raw);
-      if (!Array.isArray(parsed)) return;
-      const stored = parsed.map(parseStoredProblem);
-      if (stored.some((p) => p === null)) return;
-      const mapped = stored.map((p, index) => toResultProblem(p as StoredProblem, index, dims));
-      setDisplayProblems(mapped.filter((p) => adoptedIds.includes(p.id)));
-    } catch {
-      setDisplayProblems(problems);
+    } catch (err) {
+      console.warn("[export] sessionStorage read failed:", err);
+      return;
+    }
+    if (raw === null) return;
+    let parsed: unknown;
+    try {
+      parsed = JSON.parse(raw);
+    } catch (err) {
+      console.warn("[export] JSON parse failed:", err);
+      return;
     }
-  }, [grade, topic, mode, dims, sourceProblemText, adoptedIds, problems]);
+    if (!Array.isArray(parsed)) return;
+    const stored = parsed.map(parseStoredProblem);
+    if (stored.some((p) => p === null)) return;
+    const mapped = stored.map((p, index) => toResultProblem(p as StoredProblem, index));
+    setDisplayProblems(mapped.filter((p) => adoptedIds.includes(p.id)));
+  }, [grade, topic, mode, sourceItemId, adoptedIds, problems, schoolLevel]);
 
   /* afterprint — 사용자가 시스템 print dialog 를 닫은 시점.
    * 저장/취소 여부는 브라우저 API 가 노출하지 않으므로 일괄 "완료" 로 표기.
@@ -269,7 +259,7 @@ export function ExportView({
   }
 
   if (displayProblems.length === 0) {
-    const backHref = resultHref(schoolLevel, grade, topic, mode, dims, sourceProblemText);
+    const backHref = resultHref(schoolLevel, grade, topic, mode, sourceItemId);
     return (
       <>
         <nav className="container-app sub-nav" aria-label="단계 이동">
@@ -298,7 +288,7 @@ export function ExportView({
     /* 브라우저 print API — 시스템 dialog 에서 "PDF 로 저장" 선택. */
     window.print();
   };
-  const backHref = resultHref(schoolLevel, grade, topic, mode, dims, sourceProblemText);
+  const backHref = resultHref(schoolLevel, grade, topic, mode, sourceItemId);
 
   /* 옵션 변경 핸들러 */
   const setTitle = (v: string): void =>
diff --git a/packages/web/app/app/new/intent/page.tsx b/packages/web/app/app/new/intent/page.tsx
index 5a9da2f..a432055 100644
--- a/packages/web/app/app/new/intent/page.tsx
+++ b/packages/web/app/app/new/intent/page.tsx
@@ -1,30 +1,45 @@
 import type { Metadata } from "next";
+import { findTopic, parseGrade, parseSchoolLevel, pickFirst } from "../topic/data";
 import {
-  findTopic,
-  getEvaluationCandidates,
-  parseGrade,
-  parseSchoolLevel,
-  pickFirst,
-} from "../topic/data";
+  getSourceProblems,
+  type SourceProblem,
+} from "@/lib/source-problems-client";
 import { IntentPicker } from "./picker";
 
 export const metadata: Metadata = {
   title: "의도 확인 — OpenMath",
-  description:
-    "동형 모드와 보존해야 하는 평가 차원을 선택합니다. 출제의 핵심 단계.",
+  description: "동형 모드와 기준 문항을 선택합니다. 출제의 핵심 단계.",
 };
 
 type Props = {
-  searchParams: { school?: string | string[]; grade?: string | string[]; topic?: string | string[] };
+  searchParams: {
+    school?: string | string[];
+    grade?: string | string[];
+    topic?: string | string[];
+  };
 };
 
-export default function IntentPage({ searchParams }: Props) {
+export default async function IntentPage({ searchParams }: Props) {
   const schoolLevel = parseSchoolLevel(searchParams.school);
   const grade = parseGrade(searchParams.grade);
   const topic = findTopic(pickFirst(searchParams.topic));
-  const candidates = topic === null ? [] : getEvaluationCandidates(topic);
+
+  let candidates: SourceProblem[] = [];
+  if (topic !== null) {
+    candidates = await getSourceProblems({
+      schoolLevel,
+      grade,
+      topicCode: topic.code,
+      limit: 30,
+    });
+  }
 
   return (
-    <IntentPicker schoolLevel={schoolLevel} grade={grade} topic={topic} candidates={candidates} />
+    <IntentPicker
+      schoolLevel={schoolLevel}
+      grade={grade}
+      topic={topic}
+      candidates={candidates}
+    />
   );
 }
diff --git a/packages/web/app/app/new/intent/picker.tsx b/packages/web/app/app/new/intent/picker.tsx
index c85f563..faee75d 100644
--- a/packages/web/app/app/new/intent/picker.tsx
+++ b/packages/web/app/app/new/intent/picker.tsx
@@ -1,9 +1,8 @@
 "use client";
 
 import Link from "next/link";
-import { useState } from "react";
+import { useRef, useState } from "react";
 import {
-  type EvaluationCandidate,
   type Grade,
   type SchoolLevel,
   type Topic,
@@ -11,9 +10,14 @@ import {
   topicScopeLabel,
 } from "../topic/data";
 import { LatexMixed } from "@/components/math/latex-renderer";
-import examplesData from "../topic/examples.json";
+import {
+  type Difficulty,
+  type SourceProblem,
+  getSourceProblems,
+} from "@/lib/source-problems-client";
 
 type IsomorphismMode = "structural" | "conceptual";
+type DifficultyFilter = "all" | Difficulty;
 
 type ModeOption = {
   value: IsomorphismMode;
@@ -24,30 +28,11 @@ type ModeOption = {
   badgeText: string;
 };
 
-type ReferenceProblem = {
-  id: string;
-  title: string;
-  body: string;
-  sourceProblemText: string;
-  difficulty?: "easy" | "medium" | "hard";
-};
-
-type ExampleEntry = {
-  id: string;
-  achievement_code_2015: string;
-  topic_name_2015: string;
-  difficulty: "easy" | "medium" | "hard";
-  problem_type: "objective" | "essay" | "short_answer" | "subjective";
-  question_text: string;
-  answer_text: string;
+type DifficultyChip = {
+  value: DifficultyFilter;
+  label: string;
 };
 
-const bakedExamples = (
-  examplesData as {
-    units: Record<string, { examples: ExampleEntry[] }>;
-  }
-).units;
-
 const modes: ModeOption[] = [
   {
     value: "structural",
@@ -60,53 +45,55 @@ const modes: ModeOption[] = [
   {
     value: "conceptual",
     label: "개념 동형",
-    desc: "풀이 경로는 달라도 같은 학습 목표와 평가 차원을 보존합니다.",
+    desc: "풀이 경로는 달라도 같은 학습 목표를 보존합니다.",
     badgeClass: "badge-concept",
     badgeIcon: "✦",
     badgeText: "Conceptual",
   },
 ];
 
-function referenceProblems(topic: Topic): ReferenceProblem[] {
-  const baked = bakedExamples[topic.code]?.examples;
-  if (baked && baked.length > 0) {
-    return baked.map((ex, idx) => ({
-      id: ex.id,
-      title: `${topic.name} · 예시 ${idx + 1}`,
-      body: ex.question_text,
-      sourceProblemText: ex.question_text,
-      difficulty: ex.difficulty,
-    }));
-  }
-  return [
-    {
-      id: `${topic.code}-standard`,
-      title: `${topic.name} · 성취기준 기반`,
-      body: topic.achievement,
-      sourceProblemText: topic.achievement,
-    },
-  ];
-}
+const difficultyChips: DifficultyChip[] = [
+  { value: "all", label: "전체" },
+  { value: "hard", label: "상" },
+  { value: "medium", label: "중" },
+  { value: "easy", label: "하" },
+];
 
-function difficultyLabel(d: ReferenceProblem["difficulty"]): string | null {
-  if (d === undefined) return null;
-  return d === "easy" ? "쉬움" : d === "medium" ? "보통" : "어려움";
+function difficultyLabel(d: Difficulty): string {
+  if (d === "easy") return "하";
+  if (d === "medium") return "중";
+  return "상";
 }
 
 type Props = {
   schoolLevel: SchoolLevel;
   grade: Grade | null;
   topic: Topic | null;
-  candidates: EvaluationCandidate[];
+  candidates: SourceProblem[];
 };
 
 export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
   const [mode, setMode] = useState<IsomorphismMode | null>("structural");
-  const refs = topic === null ? [] : referenceProblems(topic);
-  const [selectedRef, setSelectedRef] = useState<string>(refs[0]?.id ?? "");
-  const [checked, setChecked] = useState<Set<string>>(
-    () => new Set(candidates.filter((c) => c.default).map((c) => c.key)),
-  );
+  const [difficulty, setDifficulty] = useState<DifficultyFilter>("all");
+  const [selectedItemId, setSelectedItemId] = useState<string>("");
+  const [displayed, setDisplayed] = useState<SourceProblem[]>(candidates);
+  const [loadingDiff, setLoadingDiff] = useState<boolean>(false);
+  const [diffError, setDiffError] = useState<boolean>(false);
+
+  /* difficulty 별 결과 캐시 — 같은 칩 재클릭 시 네트워크 왕복 회피.
+   * "all" 은 SSR set 으로 seed. ref 를 lazy-init 으로 1회만 채운다.
+   */
+  const cacheRef = useRef<Map<DifficultyFilter, SourceProblem[]> | null>(null);
+  if (cacheRef.current === null) {
+    cacheRef.current = new Map<DifficultyFilter, SourceProblem[]>([
+      ["all", candidates],
+    ]);
+  }
+
+  /* 빠른 연속 칩 클릭의 race 방어 — 늦게 도착한 응답이 최신 selection 을
+   * 덮어쓰지 않도록 request id 토큰으로 stale 응답을 식별·드롭한다.
+   */
+  const requestIdRef = useRef<number>(0);
 
   if ((schoolLevel === "middle" && grade === null) || topic === null) {
     return (
@@ -131,31 +118,167 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
     );
   }
 
-  const toggle = (key: string): void => {
-    setChecked((prev) => {
-      const next = new Set(prev);
-      if (next.has(key)) {
-        next.delete(key);
-      } else {
-        next.add(key);
+  const gradeParam = grade === null ? "common" : String(grade);
+  const sameIntentHref = `/app/new/intent?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}`;
+
+  if (candidates.length === 0) {
+    return (
+      <>
+        <nav className="container-app sub-nav" aria-label="단계 이동">
+          <div>
+            <Link
+              href={`/app/new/topic?school=${schoolLevel}&grade=${gradeParam}`}
+              className="crumb"
+            >
+              <span aria-hidden="true">←</span>
+              <span>단원 선택</span>
+            </Link>
+            <span className="crumb-sep" aria-hidden="true">·</span>
+            <span className="crumb-current">
+              {gradeLabel(grade, schoolLevel)} · {topic.name}
+            </span>
+          </div>
+          <span className="progress" aria-label="4 단계 중 3 단계">
+            (3/4) 의도 확인
+          </span>
+        </nav>
+        <main className="container-app page-body">
+          <h1 className="page-title">기준 문항을 불러오지 못했어요</h1>
+          <p className="page-subtitle">
+            현재 단원({topic.name})에 해당하는 corpus 문항이 비어 있거나
+            agent 서버에 일시적인 문제가 있을 수 있습니다. 잠시 후 다시
+            시도해 주세요.
+          </p>
+          <Link href={sameIntentHref} className="btn btn-primary" prefetch={false}>
+            <span>다시 불러오기</span>
+            <span aria-hidden="true">↻</span>
+          </Link>
+        </main>
+      </>
+    );
+  }
+
+  const topicCode = topic.code;
+
+  const loadDifficulty = async (chip: DifficultyFilter): Promise<void> => {
+    setDifficulty(chip);
+    setDiffError(false);
+
+    const cache = cacheRef.current;
+    if (cache === null) return;
+
+    const cached = cache.get(chip);
+    if (cached !== undefined) {
+      setDisplayed(cached);
+      if (
+        selectedItemId.length > 0 &&
+        !cached.some((c) => c.item_id === selectedItemId)
+      ) {
+        setSelectedItemId("");
       }
-      return next;
-    });
+      return;
+    }
+
+    if (chip === "all") {
+      /* 방어 경로 — cache 는 항상 "all" seed 를 가져야 하지만, 안전망. */
+      setDisplayed(candidates);
+      return;
+    }
+
+    const myRequestId = ++requestIdRef.current;
+    setLoadingDiff(true);
+
+    let result: SourceProblem[];
+    try {
+      result = await getSourceProblems({
+        schoolLevel,
+        grade,
+        topicCode,
+        difficulty: chip,
+        limit: 30,
+      });
+    } catch (err) {
+      if (requestIdRef.current === myRequestId) {
+        console.warn(
+          `[intent-source] difficulty=${chip} fetch threw:`,
+          err,
+        );
+        setDiffError(true);
+        setLoadingDiff(false);
+      }
+      return;
+    }
+
+    if (requestIdRef.current !== myRequestId) return;
+
+    cache.set(chip, result);
+    setDisplayed(result);
+    if (
+      selectedItemId.length > 0 &&
+      !result.some((c) => c.item_id === selectedItemId)
+    ) {
+      setSelectedItemId("");
+    }
+    setLoadingDiff(false);
+  };
+
+  const canSubmit = mode !== null && selectedItemId !== "";
+
+  /* selectedItemId 가 현재 displayed 에 있으면 거기서 → 없으면 (사용자가
+   * 선택 후 다른 칩 → 같은 칩 돌아왔으나 캐시 만료 상황 등) SSR `candidates`
+   * 에서 fallback. 둘 다 못 찾으면 stale selection 으로 null 처리.
+   */
+  const selectedProblem =
+    selectedItemId.length > 0
+      ? (displayed.find((c) => c.item_id === selectedItemId) ??
+        candidates.find((c) => c.item_id === selectedItemId) ??
+        null)
+      : null;
+
+  let generateHref: string | null = null;
+  if (canSubmit && mode !== null && selectedProblem !== null) {
+    const params = new URLSearchParams();
+    params.set("school", schoolLevel);
+    params.set("grade", gradeParam);
+    params.set("topic", topicCode);
+    params.set("mode", mode);
+    params.set("srcRef", selectedProblem.item_id);
+    generateHref = `/app/new/verify?${params.toString()}`;
+  }
+
+  const handleSubmit = (): void => {
+    if (selectedProblem === null) return;
+    try {
+      window.sessionStorage.setItem(
+        "openmath:intent-source",
+        JSON.stringify({
+          item_id: selectedProblem.item_id,
+          question_text: selectedProblem.question_text,
+          difficulty_norm: selectedProblem.difficulty_norm,
+        }),
+      );
+    } catch (err) {
+      console.warn("[intent-source] sessionStorage write failed:", err);
+    }
   };
 
-  const canSubmit = mode !== null && checked.size > 0;
-  const dims = Array.from(checked).sort().join(",");
-  const source = refs.find((ref) => ref.id === selectedRef)?.sourceProblemText ?? refs[0]?.sourceProblemText ?? "";
-  const generateHref = canSubmit
-    ? `/app/new/verify?school=${schoolLevel}&grade=${grade === null ? "common" : grade}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&dims=${dims}&source=${encodeURIComponent(source)}`
-    : null;
+  const retryButtonStyle = {
+    background: "transparent",
+    border: "none",
+    color: "var(--color-warn-deep)",
+    textDecoration: "underline",
+    cursor: "pointer",
+    font: "inherit",
+    padding: 0,
+    marginLeft: "4px",
+  } as const;
 
   return (
     <>
       <nav className="container-app sub-nav" aria-label="단계 이동">
         <div>
           <Link
-            href={`/app/new/topic?school=${schoolLevel}&grade=${grade === null ? "common" : grade}`}
+            href={`/app/new/topic?school=${schoolLevel}&grade=${gradeParam}`}
             className="crumb"
           >
             <span aria-hidden="true">←</span>
@@ -176,15 +299,11 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
           어떻게 출제할까요?
         </h1>
         <p className="page-subtitle">
-          {topicScopeLabel(topic)} 기준입니다. 동형 방식 · 기준 문항 · 보존할 평가 차원을 골라 주세요.
-          검증 6 단계가 이 기준을 따라 진행됩니다.
+          {topicScopeLabel(topic)} 기준입니다. 동형 방식과 기준 문항을 골라
+          주세요. 검증 6 단계가 이 기준을 따라 진행됩니다.
         </p>
 
-        {/* S3-A — 동형 모드 */}
-        <section
-          className="section-block"
-          aria-labelledby="mode-heading"
-        >
+        <section className="section-block" aria-labelledby="mode-heading">
           <h2 className="heading-md" id="mode-heading">
             어떤 동형으로 생성할까요?
           </h2>
@@ -219,7 +338,6 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
           </div>
         </section>
 
-        {/* S3-B — 기준 문항 */}
         <section
           className="section-block"
           aria-labelledby="reference-heading"
@@ -228,95 +346,102 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
             어떤 문제를 기준으로 만들까요?
           </h2>
           <p className="page-subtitle">
-            구조동형은 풀이 구조를, 개념동형은 학습 목표를 이 기준 문항에서 가져옵니다.
+            corpus 에서 가져온 후보 중 하나를 선택해 주세요. 구조 동형은
+            풀이 구조를, 개념 동형은 학습 목표를 이 문항에서 가져옵니다.
           </p>
-          <div
-            className="reference-list"
-            role="radiogroup"
-            aria-labelledby="reference-heading"
-          >
-            {refs.map((ref) => {
-              const diff = difficultyLabel(ref.difficulty);
+
+          <div className="filter-row" role="toolbar" aria-label="난이도 필터">
+            {difficultyChips.map((chip) => {
+              const active = difficulty === chip.value;
               return (
-                <label key={ref.id} className="intent-radio-card">
+                <button
+                  key={chip.value}
+                  type="button"
+                  className="filter-chip"
+                  aria-pressed={active}
+                  onClick={() => {
+                    void loadDifficulty(chip.value);
+                  }}
+                >
+                  {chip.label}
+                </button>
+              );
+            })}
+            {loadingDiff ? (
+              <span
+                className="meta-pill"
+                role="status"
+                aria-live="polite"
+              >
+                불러오는 중…
+              </span>
+            ) : null}
+          </div>
+
+          {diffError ? (
+            <div
+              className="inline-notice inline-notice-warn"
+              role="status"
+            >
+              <span className="icon" aria-hidden="true">
+                ⚠
+              </span>
+              <span className="body">
+                난이도별 문항을 불러오지 못했어요. 잠시 후
+                <button
+                  type="button"
+                  onClick={() => {
+                    void loadDifficulty(difficulty);
+                  }}
+                  style={retryButtonStyle}
+                >
+                  다시 시도
+                </button>
+                해 주세요.
+              </span>
+            </div>
+          ) : null}
+
+          {displayed.length === 0 ? (
+            <p className="empty-state">
+              선택한 난이도에 해당하는 문항이 없습니다. 다른 난이도를
+              선택해 주세요.
+            </p>
+          ) : (
+            <div
+              className="reference-list"
+              role="radiogroup"
+              aria-labelledby="reference-heading"
+              aria-busy={loadingDiff}
+            >
+              {displayed.map((c) => (
+                <label key={c.item_id} className="intent-radio-card">
                   <input
                     type="radio"
                     name="reference-problem"
-                    value={ref.id}
-                    checked={selectedRef === ref.id}
-                    onChange={() => setSelectedRef(ref.id)}
+                    value={c.item_id}
+                    checked={selectedItemId === c.item_id}
+                    onChange={() => setSelectedItemId(c.item_id)}
                     className="sr-only"
                   />
                   <span className="dot" aria-hidden="true" />
                   <span className="label">
                     <span className="label-main">
-                      <span>{ref.title}</span>
-                      {diff !== null ? (
-                        <span className="example-badge example-badge-diff">
-                          {diff}
-                        </span>
-                      ) : null}
+                      <span className="meta-pill">
+                        {difficultyLabel(c.difficulty_norm)}
+                      </span>
+                      <span className="example-badge example-badge-type">
+                        {c.topic_name}
+                      </span>
                     </span>
                     <span className="label-desc">
-                      <LatexMixed source={ref.body} />
+                      <LatexMixed source={c.question_text} />
                     </span>
                   </span>
                 </label>
-              );
-            })}
-          </div>
-        </section>
-
-        {/* S3-C — 평가 차원 */}
-        <section
-          className="section-block"
-          aria-labelledby="dim-heading"
-        >
-          <h2 className="heading-md" id="dim-heading">
-            보존해야 하는 능력은?
-          </h2>
-
-          <div className="inline-notice inline-notice-warn" role="note">
-            <span className="icon" aria-hidden="true">
-              ⚠
-            </span>
-            <span className="body">
-              이 차원을 보존해야 동형으로 인정됩니다. 1 개 이상
-              선택하세요.
-            </span>
-          </div>
-
-          <fieldset
-            className="dimension-list"
-            aria-required="true"
-            aria-describedby={
-              checked.size === 0 ? "dim-required-reason" : undefined
-            }
-          >
-            <legend className="sr-only">평가 차원 (1 개 이상)</legend>
-            {candidates.map((c) => (
-              <label key={c.key} className="intent-checkbox">
-                <input
-                  type="checkbox"
-                  name="dims"
-                  value={c.key}
-                  checked={checked.has(c.key)}
-                  onChange={() => toggle(c.key)}
-                  className="sr-only"
-                />
-                <span className="check-icon" aria-hidden="true" />
-                <span className="label">
-                  <span className="label-key" aria-hidden="true">
-                    [{c.key}]
-                  </span>
-                  <span className="label-text">{c.description}</span>
-                </span>
-              </label>
-            ))}
-          </fieldset>
-          <span id="dim-required-reason" className="sr-only">
-            평가 차원을 1 개 이상 선택하세요.
-          </span>
+              ))}
+            </div>
+          )}
         </section>
       </main>
 
@@ -324,7 +449,7 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
         <div className="container-app action-bar-inner">
           <div className="left">
             <Link
-              href={`/app/new/topic?grade=${grade}`}
+              href={`/app/new/topic?school=${schoolLevel}&grade=${gradeParam}`}
               className="btn btn-secondary"
             >
               <span aria-hidden="true">←</span>
@@ -333,7 +458,11 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
           </div>
           <div className="right">
             {generateHref !== null ? (
-              <Link href={generateHref} className="btn btn-primary">
+              <Link
+                href={generateHref}
+                className="btn btn-primary"
+                onClick={handleSubmit}
+              >
                 <span>생성하기</span>
                 <span aria-hidden="true">→</span>
               </Link>
@@ -349,11 +478,11 @@ export function IntentPicker({ schoolLevel, grade, topic, candidates }: Props) {
               </button>
             )}
             <span id="generate-reason" className="sr-only">
-              {mode === null && checked.size === 0
-                ? "동형 모드를 선택하고 평가 차원을 1 개 이상 선택하세요."
+              {mode === null && selectedItemId === ""
+                ? "동형 모드를 선택하고 기준 문항을 1 개 선택하세요."
                 : mode === null
                   ? "동형 모드를 선택하세요."
-                  : "평가 차원을 1 개 이상 선택하세요."}
+                  : "기준 문항을 1 개 선택하세요."}
             </span>
           </div>
         </div>
diff --git a/packages/web/app/app/new/result/mock.ts b/packages/web/app/app/new/result/mock.ts
index 5075bc2..dc8511b 100644
--- a/packages/web/app/app/new/result/mock.ts
+++ b/packages/web/app/app/new/result/mock.ts
@@ -21,8 +21,6 @@ export type ResultProblem = {
   questionLatex: string;
   answerLatex: string;
   solutionLatex: string;
-  preservedDims: string[];
-  missingDims: string[];
   failReason: string | null;
 };
 
@@ -126,7 +124,6 @@ function genericTemplate(topic: Topic): TopicTemplate {
 export function generateMockResults(
   topic: Topic,
   mode: "structural" | "conceptual",
-  dims: string[],
 ): ResultProblem[] {
   const t = templates[topic.code] ?? genericTemplate(topic);
   /* 4 문항: pass / pass / warn / fail — UI 상태 demo 용. */
@@ -134,38 +131,22 @@ export function generateMockResults(
     status: ResultStatus;
     iso: "structural" | "conceptual";
     failReason: string | null;
-    missingDimIndex: number | null;
   }> = [
-    { status: "pass", iso: mode, failReason: null, missingDimIndex: null },
+    { status: "pass", iso: mode, failReason: null },
     {
       status: "pass",
       iso: mode === "structural" ? "conceptual" : "structural",
       failReason: null,
-      missingDimIndex: null,
-    },
-    {
-      status: "warn",
-      iso: mode,
-      failReason: null,
-      missingDimIndex: dims.length >= 2 ? dims.length - 1 : null,
     },
+    { status: "warn", iso: mode, failReason: null },
     {
       status: "fail",
       iso: mode,
       failReason: "독립 재풀이에서 답 불일치 — 검토 필요",
-      missingDimIndex: null,
     },
   ];
 
   return layouts.map((layout, i) => {
-    const dimsKept =
-      layout.missingDimIndex === null
-        ? [...dims]
-        : dims.filter((_, idx) => idx !== layout.missingDimIndex);
-    const dimsMissing =
-      layout.missingDimIndex === null
-        ? []
-        : [dims[layout.missingDimIndex] ?? ""];
     return {
       id: `${topic.code}-${i + 1}`,
       number: i + 1,
@@ -174,8 +155,6 @@ export function generateMockResults(
       questionLatex: t.questions[i] ?? t.questions[0] ?? "",
       answerLatex: t.answers[i] ?? t.answers[0] ?? "",
       solutionLatex: t.solutions[i] ?? t.solutions[0] ?? "",
-      preservedDims: dimsKept,
-      missingDims: dimsMissing,
       failReason: layout.failReason,
     };
   });
diff --git a/packages/web/app/app/new/result/page.tsx b/packages/web/app/app/new/result/page.tsx
index 644c1b4..cc21304 100644
--- a/packages/web/app/app/new/result/page.tsx
+++ b/packages/web/app/app/new/result/page.tsx
@@ -14,8 +14,7 @@ type Props = {
     school?: string | string[];
     topic?: string | string[];
     mode?: string | string[];
-    dims?: string | string[];
-    source?: string | string[];
+    srcRef?: string | string[];
   };
 };
 
@@ -26,26 +25,15 @@ function parseMode(
   return null;
 }
 
-function parseDims(raw: string | null): string[] {
-  if (raw === null) return [];
-  return raw
-    .split(",")
-    .map((s) => s.trim())
-    .filter((s) => s.length > 0);
-}
-
 export default function ResultPage({ searchParams }: Props) {
   const schoolLevel = parseSchoolLevel(searchParams.school);
   const grade = parseGrade(searchParams.grade);
   const topic = findTopic(pickFirst(searchParams.topic));
   const mode = parseMode(pickFirst(searchParams.mode));
-  const dims = parseDims(pickFirst(searchParams.dims));
-  const sourceProblemText = pickFirst(searchParams.source) ?? "";
+  const srcRef = pickFirst(searchParams.srcRef) ?? "";
 
   const problems =
-    topic !== null && mode !== null
-      ? generateMockResults(topic, mode, dims)
-      : [];
+    topic !== null && mode !== null ? generateMockResults(topic, mode) : [];
 
   return (
     <ResultView
@@ -53,8 +41,7 @@ export default function ResultPage({ searchParams }: Props) {
       schoolLevel={schoolLevel}
       topic={topic}
       mode={mode}
-      dims={dims}
-      sourceProblemText={sourceProblemText}
+      sourceItemId={srcRef}
       problems={problems}
     />
   );
diff --git a/packages/web/app/app/new/result/view.tsx b/packages/web/app/app/new/result/view.tsx
index 0ba64bd..1daa406 100644
--- a/packages/web/app/app/new/result/view.tsx
+++ b/packages/web/app/app/new/result/view.tsx
@@ -4,6 +4,7 @@ import Link from "next/link";
 import { useEffect, useMemo, useState } from "react";
 import { LatexRenderer } from "@/components/math/latex-renderer";
 import { type Grade, type SchoolLevel, type Topic, gradeLabel } from "../topic/data";
+import { verificationStorageKey } from "@/lib/verification-storage-key";
 import type { ResultProblem } from "./mock";
 
 type Filter = "all" | "structural" | "conceptual" | "warn";
@@ -13,8 +14,7 @@ type Props = {
   grade: Grade | null;
   topic: Topic | null;
   mode: "structural" | "conceptual" | null;
-  dims: string[];
-  sourceProblemText: string;
+  sourceItemId: string;
   problems: ResultProblem[];
 };
 
@@ -54,7 +54,7 @@ function badgeFor(p: ResultProblem): {
       className: "badge-warn",
       icon: "⚠",
       text: "주의",
-      srLabel: "부분 통과 — 평가 차원 일부 미보존",
+      srLabel: "부분 통과 — 검토 권장",
     };
   }
   if (p.isomorphism === "structural") {
@@ -86,32 +86,6 @@ function matchesFilter(p: ResultProblem, filter: Filter): boolean {
   }
 }
 
-function storageKey(
-  schoolLevel: SchoolLevel,
-  grade: Grade | null,
-  topic: Topic,
-  mode: "structural" | "conceptual",
-  dims: string[],
-  sourceProblemText: string,
-): string {
-  return [
-    "openmath:verification-result",
-    grade,
-    schoolLevel,
-    topic.code,
-    topic.name,
-    mode,
-    [...dims].sort().join(","),
-    sourceProblemText,
-  ].join("|");
-}
-
-function sourceQuery(sourceProblemText: string): string {
-  return sourceProblemText.length > 0
-    ? `&source=${encodeURIComponent(sourceProblemText)}`
-    : "";
-}
-
 function parseStoredProblem(raw: unknown): StoredProblem | null {
   if (typeof raw !== "object" || raw === null || Array.isArray(raw)) return null;
   const o = raw as Record<string, unknown>;
@@ -133,9 +107,8 @@ function parseStoredProblem(raw: unknown): StoredProblem | null {
   };
 }
 
-function toResultProblem(problem: StoredProblem, index: number, dims: string[]): ResultProblem {
+function toResultProblem(problem: StoredProblem, index: number): ResultProblem {
   const status = problem.verification_status === "partial" ? "warn" : problem.verification_status;
-  const missingDims = dims.filter((dim) => !problem.preserved_dimensions.includes(dim));
   return {
     id: problem.id,
     number: index + 1,
@@ -144,8 +117,6 @@ function toResultProblem(problem: StoredProblem, index: number, dims: string[]):
     questionLatex: problem.question_latex,
     answerLatex: problem.answer_latex,
     solutionLatex: problem.explanation_latex ?? "검증 파이프라인에서 생성된 문항입니다.",
-    preservedDims: problem.preserved_dimensions,
-    missingDims: status === "warn" ? missingDims : [],
     failReason: status === "fail" ? "검증 실패 — 채택할 수 없습니다." : null,
   };
 }
@@ -155,8 +126,7 @@ export function ResultView({
   schoolLevel,
   topic,
   mode,
-  dims,
-  sourceProblemText,
+  sourceItemId,
   problems,
 }: Props) {
   const [filter, setFilter] = useState<Filter>("all");
@@ -166,22 +136,38 @@ export function ResultView({
   useEffect(() => {
     setDisplayProblems(problems);
     if ((schoolLevel === "middle" && grade === null) || topic === null || mode === null) return;
+    if (sourceItemId === "") return;
+    let raw: string | null = null;
     try {
-      const raw = window.sessionStorage.getItem(
-        storageKey(schoolLevel, grade, topic, mode, dims, sourceProblemText),
-      );
-      if (raw === null) return;
-      const parsed: unknown = JSON.parse(raw);
-      if (!Array.isArray(parsed)) return;
-      const stored = parsed.map(parseStoredProblem);
-      if (stored.some((p) => p === null)) return;
-      setDisplayProblems(
-        stored.map((p, index) => toResultProblem(p as StoredProblem, index, dims)),
+      raw = window.sessionStorage.getItem(
+        verificationStorageKey({
+          grade,
+          schoolLevel,
+          topic: topic.code,
+          topicName: topic.name,
+          mode,
+          sourceItemId,
+        }),
       );
-    } catch {
-      setDisplayProblems(problems);
+    } catch (err) {
+      console.warn("[result] sessionStorage read failed:", err);
+      return;
     }
-  }, [schoolLevel, grade, topic, mode, dims, sourceProblemText, problems]);
+    if (raw === null) return;
+    let parsed: unknown;
+    try {
+      parsed = JSON.parse(raw);
+    } catch (err) {
+      console.warn("[result] JSON parse failed:", err);
+      return;
+    }
+    if (!Array.isArray(parsed)) return;
+    const stored = parsed.map(parseStoredProblem);
+    if (stored.some((p) => p === null)) return;
+    setDisplayProblems(
+      stored.map((p, index) => toResultProblem(p as StoredProblem, index)),
+    );
+  }, [schoolLevel, grade, topic, mode, sourceItemId, problems]);
 
   const visible = useMemo(
     () => displayProblems.filter((p) => matchesFilter(p, filter)),
@@ -227,10 +213,11 @@ export function ResultView({
   const adoptedCount = adopted.size;
   const passedCount = displayProblems.filter((p) => p.status !== "fail").length;
   const gradeParam = grade === null ? "common" : grade;
-  const verifyHref = `/app/new/verify?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&dims=${dims.join(",")}${sourceQuery(sourceProblemText)}`;
+  const srcRefQuery = sourceItemId.length > 0 ? `&srcRef=${encodeURIComponent(sourceItemId)}` : "";
+  const verifyHref = `/app/new/verify?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}&mode=${mode}${srcRefQuery}`;
   const exportHref =
     adoptedCount > 0
-      ? `/app/new/export?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&dims=${dims.join(",")}${sourceQuery(sourceProblemText)}&adopted=${Array.from(adopted).join(",")}`
+      ? `/app/new/export?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}&mode=${mode}${srcRefQuery}&adopted=${Array.from(adopted).join(",")}`
       : null;
 
   return (
@@ -285,7 +272,6 @@ export function ResultView({
               const badge = badgeFor(p);
               const isAdopted = adopted.has(p.id);
               const failed = p.status === "fail";
-              const partial = p.status === "warn";
               return (
                 <article
                   key={p.id}
@@ -368,21 +354,6 @@ export function ResultView({
                     </div>
                   ) : null}
 
-                  {partial && p.missingDims.length > 0 ? (
-                    <div
-                      className="inline-notice inline-notice-warn"
-                      role="status"
-                    >
-                      <span className="icon" aria-hidden="true">
-                        ⚠
-                      </span>
-                      <span className="body">
-                        평가 차원 [{p.missingDims.join(", ")}] 미보존 —
-                        채택 시 학습 목표가 어긋날 수 있습니다.
-                      </span>
-                    </div>
-                  ) : null}
-
                   <div className="card-body">
                     <div className="formula-stage">
                       <LatexRenderer
diff --git a/packages/web/app/app/new/topic/data.ts b/packages/web/app/app/new/topic/data.ts
index c44500e..4ca218c 100644
--- a/packages/web/app/app/new/topic/data.ts
+++ b/packages/web/app/app/new/topic/data.ts
@@ -466,160 +466,3 @@ export function findTopic(code: string | null): Topic | null {
 export function topicsForScope(schoolLevel: SchoolLevel, grade: Grade | null): Topic[] {
   return topics.filter((topic) => topic.schoolLevel === schoolLevel && topic.grade === grade);
 }
-
-/* ───── 평가 차원 후보 (S3-B) ──────────────────────────────
- * 단원별 명시적 후보가 있으면 사용, 없으면 fallback.
- * `default` 가 true 인 항목은 페이지 진입 시 자동 체크.
- * ────────────────────────────────────────────────────── */
-
-export type EvaluationCandidate = {
-  key: string;
-  description: string;
-  default: boolean;
-};
-
-const explicitCandidates: Record<string, EvaluationCandidate[]> = {
-  "9수02-03": [
-    {
-      key: "A",
-      description: "등식의 성질을 이용한 동치 변형 단계가 명시되어야 함",
-      default: true,
-    },
-    {
-      key: "B",
-      description: "양변에 같은 수를 더하거나 빼는 절차를 정확히 수행",
-      default: true,
-    },
-    {
-      key: "C",
-      description: "이항을 사용한 항의 정리 과정이 포함",
-      default: false,
-    },
-    {
-      key: "D",
-      description: "구한 해를 원래 식에 대입하여 검증",
-      default: false,
-    },
-  ],
-  "9수02-07": [
-    {
-      key: "A",
-      description: "두 조건식에서 미지수 두 개를 연립으로 구함",
-      default: true,
-    },
-    {
-      key: "B",
-      description: "가감법 또는 대입법 중 하나의 표준 절차를 따름",
-      default: true,
-    },
-    {
-      key: "C",
-      description: "해를 두 원식에 대입하여 모두 성립함을 확인",
-      default: false,
-    },
-  ],
-  "9수02-08": [
-    {
-      key: "A",
-      description: "곱셈공식 또는 인수분해 공식을 정확히 적용",
-      default: true,
-    },
-    {
-      key: "B",
-      description: "공통인수를 먼저 분리하는 절차 포함",
-      default: false,
-    },
-    {
-      key: "C",
-      description: "완전제곱식·합차공식 등 패턴 인식",
-      default: true,
-    },
-  ],
-  "9수02-09": [
-    {
-      key: "A",
-      description: "인수분해 또는 근의 공식 중 하나로 해를 구함",
-      default: true,
-    },
-    {
-      key: "B",
-      description: "판별식을 통해 해의 개수와 종류를 해석",
-      default: false,
-    },
-    {
-      key: "C",
-      description: "구한 해를 원식에 대입하여 검증",
-      default: true,
-    },
-    {
-      key: "D",
-      description: "이차방정식의 활용 문제 풀이 단계 포함",
-      default: false,
-    },
-  ],
-  "9수03-02": [
-    {
-      key: "A",
-      description: "기울기와 y 절편의 의미를 식 · 그래프 양쪽에서 해석",
-      default: true,
-    },
-    {
-      key: "B",
-      description: "두 점 또는 한 점과 기울기에서 일차함수의 식을 구함",
-      default: true,
-    },
-    {
-      key: "C",
-      description: "그래프의 평행 · 일치 조건을 식의 계수로 해석",
-      default: false,
-    },
-  ],
-  "9수04-05": [
-    {
-      key: "A",
-      description: "직각삼각형의 변의 비로 삼각비의 값을 정의",
-      default: true,
-    },
-    {
-      key: "B",
-      description: "특수각 (30°, 45°, 60°) 의 삼각비 값을 활용",
-      default: true,
-    },
-    {
-      key: "C",
-      description: "삼각비를 이용한 변의 길이 또는 각의 크기 계산",
-      default: false,
-    },
-  ],
-};
-
-function fallbackCandidates(topic: Topic): EvaluationCandidate[] {
-  return [
-    {
-      key: "A",
-      description: `${topic.name} 의 핵심 개념과 정의를 정확히 적용`,
-      default: true,
-    },
-    {
-      key: "B",
-      description: `${topic.name} 의 표준 풀이 절차를 단계별로 수행`,
-      default: true,
-    },
-    {
-      key: "C",
-      description: "식 또는 그림의 변형이 정의된 성질에 부합",
-      default: false,
-    },
-    {
-      key: "D",
-      description: "구한 결과를 원래 조건에 대입하여 검증",
-      default: false,
-    },
-  ];
-}
-
-export function getEvaluationCandidates(
-  topic: Topic,
-): EvaluationCandidate[] {
-  return explicitCandidates[topic.code] ?? fallbackCandidates(topic);
-}
diff --git a/packages/web/app/app/new/verify/page.tsx b/packages/web/app/app/new/verify/page.tsx
index a6f29d3..0d498dd 100644
--- a/packages/web/app/app/new/verify/page.tsx
+++ b/packages/web/app/app/new/verify/page.tsx
@@ -13,8 +13,7 @@ type Props = {
     school?: string | string[];
     topic?: string | string[];
     mode?: string | string[];
-    dims?: string | string[];
-    source?: string | string[];
+    srcRef?: string | string[];
   };
 };
 
@@ -23,21 +22,12 @@ function parseMode(raw: string | null): "structural" | "conceptual" | null {
   return null;
 }
 
-function parseDims(raw: string | null): string[] {
-  if (raw === null) return [];
-  return raw
-    .split(",")
-    .map((s) => s.trim())
-    .filter((s) => s.length > 0);
-}
-
 export default function VerifyPage({ searchParams }: Props) {
   const schoolLevel = parseSchoolLevel(searchParams.school);
   const grade = parseGrade(searchParams.grade);
   const topic = findTopic(pickFirst(searchParams.topic));
   const mode = parseMode(pickFirst(searchParams.mode));
-  const dims = parseDims(pickFirst(searchParams.dims));
-  const sourceProblemText = pickFirst(searchParams.source) ?? "";
+  const srcRef = pickFirst(searchParams.srcRef) ?? "";
 
   return (
     <VerifyView
@@ -45,8 +35,7 @@ export default function VerifyPage({ searchParams }: Props) {
       schoolLevel={schoolLevel}
       topic={topic}
       mode={mode}
-      dims={dims}
-      sourceProblemText={sourceProblemText}
+      srcRef={srcRef}
     />
   );
 }
diff --git a/packages/web/app/app/new/verify/view.tsx b/packages/web/app/app/new/verify/view.tsx
index a96f074..e3694c4 100644
--- a/packages/web/app/app/new/verify/view.tsx
+++ b/packages/web/app/app/new/verify/view.tsx
@@ -1,7 +1,7 @@
 "use client";
 
 import Link from "next/link";
-import { useMemo, useRef } from "react";
+import { useEffect, useMemo, useRef, useState } from "react";
 import { LatexRenderer } from "@/components/math/latex-renderer";
 import {
   type Grade,
@@ -20,8 +20,13 @@ type Props = {
   grade: Grade | null;
   topic: Topic | null;
   mode: "structural" | "conceptual" | null;
-  dims: string[];
-  sourceProblemText: string;
+  srcRef: string;
+};
+
+type IntentSource = {
+  item_id: string;
+  question_text: string;
+  difficulty_norm: "easy" | "medium" | "hard";
 };
 
 const STATUS_ICON: Record<Step["status"], string> = {
@@ -91,41 +96,79 @@ function stateLabel(status: Step["status"]): string {
   }
 }
 
-function sourceQuery(sourceProblemText: string): string {
-  return sourceProblemText.length > 0
-    ? `&source=${encodeURIComponent(sourceProblemText)}`
-    : "";
+function parseIntentSource(raw: unknown): IntentSource | null {
+  if (typeof raw !== "object" || raw === null || Array.isArray(raw)) return null;
+  const o = raw as Record<string, unknown>;
+  if (typeof o.item_id !== "string" || o.item_id.length === 0) return null;
+  if (typeof o.question_text !== "string") return null;
+  if (
+    o.difficulty_norm !== "easy" &&
+    o.difficulty_norm !== "medium" &&
+    o.difficulty_norm !== "hard"
+  ) {
+    return null;
+  }
+  return {
+    item_id: o.item_id,
+    question_text: o.question_text,
+    difficulty_norm: o.difficulty_norm,
+  };
 }
 
-export function VerifyView({ schoolLevel, grade, topic, mode, dims, sourceProblemText }: Props) {
-  const valid =
-    (schoolLevel === "high" || grade !== null) && topic !== null && mode !== null && dims.length > 0;
+export function VerifyView({ schoolLevel, grade, topic, mode, srcRef }: Props) {
+  const [intentSource, setIntentSource] = useState<IntentSource | null>(null);
+  const [hydrated, setHydrated] = useState<boolean>(false);
 
-  const input: StreamInput | null = useMemo(() => {
-    if (!valid || topic === null || mode === null) {
-      return null;
+  useEffect(() => {
+    setHydrated(true);
+    if (srcRef.length === 0) return;
+    let raw: string | null = null;
+    try {
+      raw = window.sessionStorage.getItem("openmath:intent-source");
+    } catch (err) {
+      console.warn("[intent-source] sessionStorage read failed:", err);
+      return;
+    }
+    if (raw === null) return;
+    let parsed: unknown;
+    try {
+      parsed = JSON.parse(raw);
+    } catch (err) {
+      console.warn("[intent-source] JSON parse failed:", err);
+      return;
     }
+    const validated = parseIntentSource(parsed);
+    if (validated === null) return;
+    if (validated.item_id !== srcRef) return;
+    setIntentSource(validated);
+  }, [srcRef]);
+
+  const sourceItemId = intentSource?.item_id ?? "";
+  const sourceProblemText = intentSource?.question_text ?? "";
+
+  const gateValid =
+    (schoolLevel === "high" || grade !== null) &&
+    topic !== null &&
+    mode !== null &&
+    sourceItemId !== "";
+
+  const input: StreamInput | null = useMemo(() => {
+    if (!gateValid || topic === null || mode === null) return null;
     return {
       schoolLevel,
       grade,
       topic: topic.code,
       topicName: topic.name,
       mode,
-      dims,
+      sourceItemId,
       sourceProblemText,
     };
-  }, [valid, schoolLevel, grade, topic, mode, dims, sourceProblemText]);
+  }, [gateValid, schoolLevel, grade, topic, mode, sourceItemId, sourceProblemText]);
 
-  /* hook 은 input 이 null 이면 stream 을 시작하지 않는다. invalid 가드. */
   const stream = useVerificationStream(input);
-
-  /* 자동 라우팅: status === "done" 시 S5 로 이동.
-   * router.push 는 useEffect 없이 호출하면 SSR 단계 미스매치. 일단
-   * S5 미구현이므로 inline-notice + 수동 링크로 처리. (다음 PR 에서 router.push)
-   */
   const announceRef = useRef<HTMLDivElement | null>(null);
 
-  if (!valid) {
+  if ((schoolLevel === "middle" && grade === null) || topic === null || mode === null) {
     return (
       <>
         <nav className="container-app sub-nav" aria-label="단계 이동">
@@ -137,7 +180,7 @@ export function VerifyView({ schoolLevel, grade, topic, mode, dims, sourceProble
         <main className="container-app page-body">
           <h1 className="page-title">이전 단계 정보가 필요해요</h1>
           <p className="page-subtitle">
-            학년 · 단원 · 동형 모드 · 평가 차원 중 하나가 누락되었습니다.
+            학년 · 단원 · 동형 모드 중 하나가 누락되었습니다.
           </p>
           <Link href="/app/new/grade" className="btn btn-primary">
             <span>학년 선택으로</span>
@@ -148,17 +191,48 @@ export function VerifyView({ schoolLevel, grade, topic, mode, dims, sourceProble
     );
   }
 
+  const gradeParam = grade === null ? "common" : String(grade);
+  const intentHref = `/app/new/intent?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}`;
+
+  if (hydrated && (srcRef.length === 0 || intentSource === null)) {
+    return (
+      <>
+        <nav className="container-app sub-nav" aria-label="단계 이동">
+          <Link href={intentHref} className="crumb">
+            <span aria-hidden="true">←</span>
+            <span>의도 확인</span>
+          </Link>
+        </nav>
+        <main className="container-app page-body">
+          <h1 className="page-title">기준 문항을 다시 선택해 주세요</h1>
+          <p className="page-subtitle">
+            검증을 시작하려면 의도 확인 화면에서 기준 문항을 1 개 골라야
+            합니다. 세션이 만료되었거나 직접 URL 로 접근한 경우 다시
+            선택해 주세요.
+          </p>
+          <Link href={intentHref} className="btn btn-primary">
+            <span>의도 확인으로</span>
+            <span aria-hidden="true">→</span>
+          </Link>
+        </main>
+      </>
+    );
+  }
+
   const subnavLabel = `${gradeLabel(grade, schoolLevel)} · ${topic.name}`;
   const isError = stream.status === "error";
   const isCancelled = stream.status === "cancelled";
   const isDone = stream.status === "done";
   const showPreview = stream.previewLatex !== null;
 
+  const verifyHref = `/app/new/verify?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&srcRef=${encodeURIComponent(srcRef)}`;
+  const resultHref = `/app/new/result?school=${schoolLevel}&grade=${gradeParam}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&srcRef=${encodeURIComponent(srcRef)}`;
+
   return (
     <>
       <nav className="container-app sub-nav" aria-label="단계 이동">
         <div>
-          <Link href="/app/new/intent" className="crumb">
+          <Link href={intentHref} className="crumb">
             <span aria-hidden="true">←</span>
             <span>의도 확인</span>
           </Link>
@@ -240,7 +314,7 @@ export function VerifyView({ schoolLevel, grade, topic, mode, dims, sourceProble
         <div className="container-app action-bar-inner">
           <div className="left">
             {isError || isCancelled ? (
-              <Link href="/app/new/intent" className="btn btn-secondary">
+              <Link href={intentHref} className="btn btn-secondary">
                 <span aria-hidden="true">←</span>
                 <span>의도 확인으로</span>
               </Link>
@@ -258,7 +332,7 @@ export function VerifyView({ schoolLevel, grade, topic, mode, dims, sourceProble
           <div className="right">
             {isError || isCancelled ? (
               <Link
-                href={`/app/new/verify?school=${schoolLevel}&grade=${grade === null ? "common" : grade}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&dims=${dims.join(",")}${sourceQuery(sourceProblemText)}`}
+                href={verifyHref}
                 className="btn btn-primary"
                 prefetch={false}
                 replace
@@ -267,10 +341,7 @@ export function VerifyView({ schoolLevel, grade, topic, mode, dims, sourceProble
                 <span aria-hidden="true">→</span>
               </Link>
             ) : isDone ? (
-              <Link
-                href={`/app/new/result?school=${schoolLevel}&grade=${grade === null ? "common" : grade}&topic=${encodeURIComponent(topic.code)}&mode=${mode}&dims=${dims.join(",")}${sourceQuery(sourceProblemText)}`}
-                className="btn btn-primary"
-              >
+              <Link href={resultHref} className="btn btn-primary">
                 <span>결과 보기</span>
                 <span aria-hidden="true">→</span>
               </Link>
diff --git a/packages/web/app/globals.css b/packages/web/app/globals.css
index 11c874a..9ca5c61 100644
--- a/packages/web/app/globals.css
+++ b/packages/web/app/globals.css
@@ -1372,107 +1372,53 @@
     }
   }
 
-  /* reference-list (S3-B) — 기준 문항 라디오 1-column. corpus 문제 길이가 가변이라 카드 높이 들쭉날쭉 + KaTeX inline 폭 보존 위해 stack 레이아웃. */
+  /* reference-list (S3-B) — 기준 문항 라디오. auto-fit minmax 으로 1280
+   * container 안에서 자동으로 다열 정렬 (≥2 cols @ 1440), 카드별 KaTeX 폭은
+   * label-desc 의 overflow-x:auto 가 흡수. 미리보기는 3줄 clamp+min-height 로
+   * 균일, 선택한 카드만 전문 펼침; 펼친 카드가 옆을 안 늘리게 align-items:start.
+   */
   .reference-list {
-    display: flex;
-    flex-direction: column;
-    gap: 12px;
-  }
-  .reference-list .intent-radio-card .label-desc {
-    overflow-wrap: anywhere;
-  }
-  .reference-list .intent-radio-card .label-desc .katex {
-    max-width: 100%;
-    overflow-x: auto;
-  }
-
-  /* dimension-list (S3-B vertical stack) */
-  .dimension-list {
-    display: flex;
-    flex-direction: column;
-    gap: 10px;
-  }
-
-  /* intent-checkbox — DESIGN.md {component.intent-checkbox} / {component.intent-checkbox-active} */
-  .intent-checkbox {
-    background: var(--color-canvas-pure);
-    color: var(--color-ink);
-    font-family: var(--font-sans);
-    font-size: 16px;
-    font-weight: 400;
-    line-height: 1.55;
-    border: 1px solid var(--color-hairline);
-    border-radius: 8px;
-    padding: 14px 18px;
-    display: flex;
-    align-items: flex-start;
-    gap: 12px;
-    cursor: pointer;
-    transition: border-color 150ms ease, background-color 150ms ease;
-    user-select: none;
-  }
-  .intent-checkbox:hover {
-    border-color: var(--color-ink-3);
-  }
-  .intent-checkbox:has(input:checked) {
-    background: var(--color-soft-cloud);
-    border: 2px solid var(--color-ink);
-    padding: 13px 17px;
-  }
-  .intent-checkbox:focus-within {
-    outline: 2px solid var(--color-primary);
-    outline-offset: 2px;
-  }
-  .intent-checkbox .check-icon {
-    width: 20px;
-    height: 20px;
-    border-radius: 4px;
-    border: 2px solid var(--color-hairline);
-    background: var(--color-canvas-pure);
-    flex-shrink: 0;
-    margin-top: 1px;
-    position: relative;
     display: grid;
-    place-items: center;
-    transition: background-color 100ms ease, border-color 100ms ease;
+    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
+    gap: 12px;
+    align-items: start;
   }
-  .intent-checkbox:has(input:checked) .check-icon {
-    background: var(--color-ink);
-    border-color: var(--color-ink);
+  .reference-list .intent-radio-card {
+    padding: 12px 14px;
   }
-  .intent-checkbox:has(input:checked) .check-icon::after {
-    content: "";
-    width: 10px;
-    height: 5px;
-    border-left: 2px solid var(--color-on-ink);
-    border-bottom: 2px solid var(--color-on-ink);
-    transform: rotate(-45deg) translate(1px, -1px);
+  .reference-list .intent-radio-card:has(input:checked) {
+    padding: 11px 13px;
   }
-  .intent-checkbox .label {
-    flex: 1;
-    min-width: 0;
-    display: flex;
-    align-items: baseline;
-    gap: 10px;
-    flex-wrap: wrap;
+  .reference-list .intent-radio-card .label {
+    gap: 8px;
   }
-  .intent-checkbox .label-key {
-    font-family: var(--font-mono);
-    font-size: 11.5px;
-    font-weight: 500;
-    letter-spacing: 0.04em;
+  .reference-list .intent-radio-card .label-main {
+    font-size: 13px;
+    gap: 6px;
     color: var(--color-ink-3);
-    flex-shrink: 0;
   }
-  .intent-checkbox:has(input:checked) .label-key {
+  .reference-list .intent-radio-card .label-desc {
+    overflow-wrap: anywhere;
     color: var(--color-ink);
+    display: -webkit-box;
+    -webkit-box-orient: vertical;
+    -webkit-line-clamp: 3;
+    line-clamp: 3;
+    overflow: hidden;
+    min-height: 5.5em;
+    max-height: 5.5em;
   }
-  .intent-checkbox .label-text {
-    font-size: 15px;
-    line-height: 1.5;
-    color: var(--color-ink);
-    flex: 1;
-    min-width: 0;
+  .reference-list .intent-radio-card:has(input:checked) .label-desc {
+    display: block;
+    -webkit-line-clamp: none;
+    line-clamp: none;
+    overflow: visible;
+    min-height: 0;
+    max-height: none;
+  }
+  .reference-list .intent-radio-card .label-desc .katex {
+    max-width: 100%;
+    overflow-x: auto;
   }
 
   /* badges — DESIGN.md {component.badge-pass|fail|concept|warn} */
@@ -2580,8 +2526,6 @@
     .job-entry-card,
     .btn-secondary,
     .intent-radio-card,
-    .intent-checkbox,
-    .intent-checkbox .check-icon,
     .filter-chip,
     .sub-nav .crumb,
     .spinner-dot,
diff --git a/packages/web/components/math/latex-renderer.tsx b/packages/web/components/math/latex-renderer.tsx
index 4119df3..5df101e 100644
--- a/packages/web/components/math/latex-renderer.tsx
+++ b/packages/web/components/math/latex-renderer.tsx
@@ -83,12 +83,12 @@ type LatexMixedProps = {
   source: string;
 };
 
-type Segment =
+export type Segment =
   | { kind: "text"; value: string }
   | { kind: "inline"; latex: string }
   | { kind: "block"; latex: string };
 
-function splitDelimited(source: string): Segment[] {
+export function splitDelimited(source: string): Segment[] {
   const out: Segment[] = [];
   let i = 0;
   let buf = "";
@@ -131,6 +131,30 @@ function splitDelimited(source: string): Segment[] {
       i = end + 1;
       continue;
     }
+    if (ch === "\\" && source[i + 1] === "[") {
+      const end = source.indexOf("\\]", i + 2);
+      if (end === -1) {
+        buf += source.slice(i);
+        i = source.length;
+        break;
+      }
+      flushText();
+      out.push({ kind: "block", latex: source.slice(i + 2, end) });
+      i = end + 2;
+      continue;
+    }
+    if (ch === "\\" && source[i + 1] === "(") {
+      const end = source.indexOf("\\)", i + 2);
+      if (end === -1) {
+        buf += source.slice(i);
+        i = source.length;
+        break;
+      }
+      flushText();
+      out.push({ kind: "inline", latex: source.slice(i + 2, end) });
+      i = end + 2;
+      continue;
+    }
     buf += ch;
     i += 1;
   }
diff --git a/packages/web/hooks/use-verification-stream.ts b/packages/web/hooks/use-verification-stream.ts
index 390fc50..7233d72 100644
--- a/packages/web/hooks/use-verification-stream.ts
+++ b/packages/web/hooks/use-verification-stream.ts
@@ -5,6 +5,7 @@ import {
   type EventSourceMessage,
 } from "@microsoft/fetch-event-source";
 import { useEffect, useReducer, useRef } from "react";
+import { verificationStorageKey } from "@/lib/verification-storage-key";
 
 /* ─────────────────────────────────────────────────────────────
  * SSE 컨트랙트 (packages/web/README.md §"SSE Consumption" + D-6)
@@ -67,7 +68,7 @@ export type StreamInput = {
   topic: string;
   topicName: string;
   mode: "structural" | "conceptual";
-  dims: readonly string[];
+  sourceItemId: string;
   sourceProblemText?: string;
   /** override agent endpoint. defaults to NEXT_PUBLIC_AGENT_URL or localhost:31415 */
   endpoint?: string;
@@ -245,19 +246,6 @@ function defaultEndpoint(): string {
   return env ?? "http://localhost:31415";
 }
 
-function verificationStorageKey(input: StreamInput): string {
-  return [
-    "openmath:verification-result",
-    input.grade,
-    input.schoolLevel,
-    input.topic,
-    input.topicName,
-    input.mode,
-    [...input.dims].sort().join(","),
-    input.sourceProblemText ?? "",
-  ].join("|");
-}
-
 export type UseVerificationStreamResult = StreamState & {
   cancel: () => void;
 };
@@ -270,14 +258,13 @@ export function useVerificationStream(
   const dispatchRef = useRef(dispatch);
   dispatchRef.current = dispatch;
 
-  /* input 의 dims 배열 동일성 비교를 위해 안정 키 생성.
-   * inputKey 는 input 의 모든 의미상 식별자를 직렬화하므로 effect deps 로 충분.
+  /* inputKey 는 input 의 모든 의미상 식별자를 직렬화한 안정 키.
+   * effect deps 에 input 객체를 직접 넣으면 부모 re-render 마다 SSE 재연결.
    */
-  const dimsKey = input === null ? "" : [...input.dims].sort().join(",");
   const inputKey =
     input === null
       ? null
-      : `${input.schoolLevel}|${input.grade ?? "common"}|${input.topic}|${input.topicName}|${input.mode}|${dimsKey}|${input.sourceProblemText ?? ""}|${input.endpoint ?? ""}`;
+      : `${input.schoolLevel}|${input.grade ?? "common"}|${input.topic}|${input.topicName}|${input.mode}|${input.sourceItemId}|${input.sourceProblemText ?? ""}|${input.endpoint ?? ""}`;
 
   /* effect 본문이 input 의 *최신* 값을 읽어야 하지만 deps 로 넣으면 가드가
    * 무효화되어 부모 re-render 마다 SSE 재연결이 발생한다 (PR #7 리뷰).
@@ -320,7 +307,7 @@ export function useVerificationStream(
         topic: current.topic,
         topic_name: current.topicName,
         mode: current.mode,
-        dims: [...current.dims].sort(),
+        source_item_id: current.sourceItemId,
         source_problem_text: current.sourceProblemText,
       }),
       signal: controller.signal,
@@ -382,11 +369,21 @@ export function useVerificationStream(
             }
             try {
               window.sessionStorage.setItem(
-                verificationStorageKey(current),
+                verificationStorageKey({
+                  grade: current.grade,
+                  schoolLevel: current.schoolLevel,
+                  topic: current.topic,
+                  topicName: current.topicName,
+                  mode: current.mode,
+                  sourceItemId: current.sourceItemId,
+                }),
                 JSON.stringify(candidates),
               );
-            } catch {
-              /* sessionStorage is an optimization for S5/S6 handoff. */
+            } catch (err) {
+              console.warn(
+                "[verification-stream] sessionStorage write failed:",
+                err,
+              );
             }
             dispatchRef.current({ type: "RESULT", candidates });
             controller.abort();
diff --git a/packages/web/lib/source-problems-client.ts b/packages/web/lib/source-problems-client.ts
new file mode 100644
index 0000000..f09684a
--- /dev/null
+++ b/packages/web/lib/source-problems-client.ts
@@ -0,0 +1,166 @@
+/* ─────────────────────────────────────────────────────────────
+ * source-problems-client — agent `/api/source-problems` 의 fetch 래퍼.
+ *
+ * Dual-use:
+ *  (1) Server Component (intent/page.tsx) 가 SSR 초기 30개 fetch.
+ *  (2) Client component (intent/picker.tsx) 가 difficulty 칩 클릭마다 refetch.
+ *
+ * 두 경우 모두 `fetch` + `process.env.NEXT_PUBLIC_AGENT_URL` 만 사용 — Next
+ * 가 NEXT_PUBLIC_ 변수를 클라이언트 번들에 인라인하므로 별도 marker 불필요.
+ * CORS 는 agent 가 :27182 에서 GET 허용.
+ *
+ * 본 모듈은 throw 하지 않는다. agent 부재·404·malformed body 모두
+ * 빈 배열 + warn. UI 가 empty-state 또는 retry 를 자체적으로 그린다.
+ * ──────────────────────────────────────────────────────────── */
+
+export type Difficulty = "easy" | "medium" | "hard";
+
+export type SourceProblem = {
+  item_id: string;
+  question_text: string;
+  answer_text: string;
+  topic_name: string;
+  topic_code: string | null;
+  difficulty_norm: Difficulty;
+  problem_type_norm: string;
+  explanation_text: string | null;
+  choice_blocks: string[] | null;
+};
+
+function getAgentBaseUrl(): string {
+  const env =
+    typeof process !== "undefined" ? process.env.NEXT_PUBLIC_AGENT_URL : undefined;
+  return (env ?? "http://localhost:31415").replace(/\/$/, "");
+}
+
+function isObject(v: unknown): v is Record<string, unknown> {
+  return typeof v === "object" && v !== null && !Array.isArray(v);
+}
+
+function isDifficulty(v: unknown): v is Difficulty {
+  return v === "easy" || v === "medium" || v === "hard";
+}
+
+function asStringArrayOrNull(v: unknown): string[] | null {
+  if (v === null) return null;
+  if (!Array.isArray(v)) return null;
+  const out: string[] = [];
+  for (const item of v) {
+    if (typeof item !== "string") return null;
+    out.push(item);
+  }
+  return out;
+}
+
+function asSourceProblem(raw: unknown): SourceProblem | null {
+  if (!isObject(raw)) return null;
+  const {
+    item_id,
+    question_text,
+    answer_text,
+    topic_name,
+    topic_code,
+    difficulty_norm,
+    problem_type_norm,
+    explanation_text,
+    choice_blocks,
+  } = raw;
+
+  if (typeof item_id !== "string" || item_id.length === 0) return null;
+  if (typeof question_text !== "string") return null;
+  if (typeof answer_text !== "string") return null;
+  if (typeof topic_name !== "string") return null;
+  if (topic_code !== null && typeof topic_code !== "string") return null;
+  if (!isDifficulty(difficulty_norm)) return null;
+  if (typeof problem_type_norm !== "string") return null;
+  if (explanation_text !== null && typeof explanation_text !== "string") return null;
+
+  const blocks =
+    choice_blocks === undefined ? null : asStringArrayOrNull(choice_blocks);
+  /* choice_blocks 는 string[] | null 이어야 하므로 undefined 도 null 로 강등. */
+
+  return {
+    item_id,
+    question_text,
+    answer_text,
+    topic_name,
+    topic_code,
+    difficulty_norm,
+    problem_type_norm,
+    explanation_text,
+    choice_blocks: blocks,
+  };
+}
+
+type GetArgs = {
+  schoolLevel: string;
+  grade: number | null;
+  topicCode: string;
+  difficulty?: Difficulty;
+  limit?: number;
+};
+
+export async function getSourceProblems(
+  args: GetArgs,
+): Promise<SourceProblem[]> {
+  const params = new URLSearchParams();
+  params.set("school_level", args.schoolLevel);
+  params.set("grade", args.grade === null ? "null" : String(args.grade));
+  params.set("topic_code", args.topicCode);
+  if (args.difficulty !== undefined) {
+    params.set("difficulty", args.difficulty);
+  }
+  const limit = args.limit === undefined ? 30 : args.limit;
+  params.set("limit", String(limit));
+
+  const url = `${getAgentBaseUrl()}/api/source-problems?${params.toString()}`;
+
+  let response: Response;
+  try {
+    response = await fetch(url, { cache: "no-store" });
+  } catch (err) {
+    const reason = err instanceof Error ? err.message : String(err);
+    console.warn(`[source-problems] fetch failed for ${url}: ${reason}`);
+    return [];
+  }
+
+  if (!response.ok) {
+    console.warn(
+      `[source-problems] non-2xx (${response.status} ${response.statusText}) for ${url}`,
+    );
+    return [];
+  }
+
+  let payload: unknown;
+  try {
+    payload = await response.json();
+  } catch (err) {
+    const reason = err instanceof Error ? err.message : String(err);
+    console.warn(`[source-problems] JSON parse failed for ${url}: ${reason}`);
+    return [];
+  }
+
+  if (!Array.isArray(payload)) {
+    console.warn(
+      `[source-problems] expected array, received ${typeof payload} for ${url}`,
+    );
+    return [];
+  }
+
+  const out: SourceProblem[] = [];
+  let skipped = 0;
+  for (const item of payload) {
+    const sp = asSourceProblem(item);
+    if (sp === null) {
+      skipped += 1;
+      continue;
+    }
+    out.push(sp);
+  }
+  if (skipped > 0) {
+    console.warn(
+      `[source-problems] skipped ${skipped}/${payload.length} malformed entries for ${url}`,
+    );
+  }
+  return out;
+}
diff --git a/packages/web/lib/verification-storage-key.ts b/packages/web/lib/verification-storage-key.ts
new file mode 100644
index 0000000..15b33ec
--- /dev/null
+++ b/packages/web/lib/verification-storage-key.ts
@@ -0,0 +1,22 @@
+export type VerificationStorageKeyParts = {
+  grade: 1 | 2 | 3 | null;
+  schoolLevel: "middle" | "high";
+  topic: string;
+  topicName: string;
+  mode: "structural" | "conceptual";
+  sourceItemId: string;
+};
+
+export function verificationStorageKey(
+  p: VerificationStorageKeyParts,
+): string {
+  return [
+    "openmath:verification-result",
+    p.grade,
+    p.schoolLevel,
+    p.topic,
+    p.topicName,
+    p.mode,
+    p.sourceItemId,
+  ].join("|");
+}
diff --git a/packages/web/tsconfig.json b/packages/web/tsconfig.json
index 1ee9409..3847f1b 100644
--- a/packages/web/tsconfig.json
+++ b/packages/web/tsconfig.json
@@ -24,5 +24,5 @@
     "**/*.tsx",
     ".next/types/**/*.ts"
   ],
-  "exclude": ["node_modules", ".next"]
+  "exclude": ["node_modules", ".next", "__tests__"]
 }