diff --git a/api-report/apps/api/src/modules/org/index.d.ts b/api-report/apps/api/src/modules/org/index.d.ts
index 95bcc39..883af8b 100644
--- a/api-report/apps/api/src/modules/org/index.d.ts
+++ b/api-report/apps/api/src/modules/org/index.d.ts
@@ -18,3 +18,5 @@ export { identityOf, isNoiseRole, normalizeRoles } from './internal/domain/claim
 export { assertNotLockedOut, endsOf, normalizeEnds } from './internal/domain/ends.ts';
 export { buildInFlightWork } from './internal/domain/in-flight.ts';
 export { DEFAULT_ROLE_ACCESS, NONE_POSITION_CODE, TEST_POSITION_CODE } from './internal/domain/seed-data.ts';
+export { createKeycloakTokenVerifier, explainJoseError } from './internal/adapter/keycloak-token-verifier.ts';
+export type { KeycloakVerifierOptions } from './internal/adapter/keycloak-token-verifier.ts';
diff --git a/apps/api/package.json b/apps/api/package.json
index 48c9895..58571f6 100644
--- a/apps/api/package.json
+++ b/apps/api/package.json
@@ -26,6 +26,7 @@
     "ajv-formats": "^3.0.1",
     "drizzle-orm": "^0.45.2",
     "hono": "^4.12.32",
+    "jose": "^5.10.0",
     "pg": "^8.22.0",
     "pg-boss": "^12.26.3",
     "zod": "^4.4.3"
diff --git a/apps/api/src/modules/org/__tests__/keycloak-token-verifier.test.ts b/apps/api/src/modules/org/__tests__/keycloak-token-verifier.test.ts
new file mode 100644
index 0000000..85187f3
--- /dev/null
+++ b/apps/api/src/modules/org/__tests__/keycloak-token-verifier.test.ts
@@ -0,0 +1,121 @@
+/**
+ * Keycloak 是外界,替身只能在外界:这里用本地密钥对充当它的 JWKS(`createLocalJWKSet`),
+ * 验签逻辑本身一行不假 —— 与生产走的是同一个 `jwtVerify`。
+ */
+import { beforeAll, describe, expect, it } from 'vitest';
+import { SignJWT, UnsecuredJWT, createLocalJWKSet, exportJWK, generateKeyPair } from 'jose';
+import type { JWK, JWTVerifyGetKey } from 'jose';
+import { TokenRejectedError } from '../contract.ts';
+import { createKeycloakTokenVerifier } from '../internal/adapter/keycloak-token-verifier.ts';
+import type { TokenVerifier } from '../port.ts';
+
+const ISSUER = 'https://keycloak.test/realms/corp';
+const AUDIENCE = 'api-gateway';
+
+let privateKey: Awaited<ReturnType<typeof generateKeyPair>>['privateKey'];
+let getKey: JWTVerifyGetKey;
+let verifier: TokenVerifier;
+
+beforeAll(async () => {
+  const pair = await generateKeyPair('RS256');
+  privateKey = pair.privateKey;
+  const jwk: JWK = { ...(await exportJWK(pair.publicKey)), kid: 'k1', alg: 'RS256', use: 'sig' };
+  getKey = createLocalJWKSet({ keys: [jwk] });
+  verifier = createKeycloakTokenVerifier({ issuer: ISSUER, audience: AUDIENCE, getKey });
+});
+
+type Mint = {
+  sub?: string;
+  issuer?: string;
+  audience?: string | string[];
+  /** 秒级 unix 时刻;缺省 5 分钟后 */
+  exp?: number;
+  kid?: string;
+  claims?: Record<string, unknown>;
+};
+
+const nowSec = (): number => Math.floor(Date.now() / 1000);
+
+async function mint(o: Mint = {}): Promise<string> {
+  const jwt = new SignJWT({
+    preferred_username: 'alice',
+    name: '爱丽丝',
+    email: 'alice@akhr-ai.com',
+    realm_access: { roles: ['user', 'default-roles-corp'] },
+    ...o.claims,
+  })
+    .setProtectedHeader({ alg: 'RS256', kid: o.kid ?? 'k1' })
+    .setSubject(o.sub ?? 'sub-alice')
+    .setIssuer(o.issuer ?? ISSUER)
+    .setAudience(o.audience ?? [AUDIENCE, 'account'])
+    .setIssuedAt()
+    .setExpirationTime(o.exp ?? nowSec() + 300);
+  return jwt.sign(privateKey);
+}
+
+describe('Keycloak 验签', () => {
+  it('RS256 · iss · aud 都对 → 返回 claims', async () => {
+    const claims = await verifier.verify(await mint());
+    expect(claims.sub).toBe('sub-alice');
+    expect(claims.preferred_username).toBe('alice');
+    expect(claims.name).toBe('爱丽丝');
+    expect(claims.realm_access?.roles).toContain('user');
+  });
+
+  it('过期 30 秒内(时钟容差)仍通过', async () => {
+    await expect(verifier.verify(await mint({ exp: nowSec() - 10 }))).resolves.toBeDefined();
+  });
+
+  it('过期超过容差 → 拒,话是「已过期」', async () => {
+    await expect(verifier.verify(await mint({ exp: nowSec() - 120 }))).rejects.toThrow(/已过期/);
+  });
+
+  it('aud 不含本服务 → 拒,话点名 audience mapper', async () => {
+    await expect(verifier.verify(await mint({ audience: ['data-service'] }))).rejects.toThrow(/audience mapper/);
+  });
+
+  it('iss 不符 → 拒,话点名 KEYCLOAK_URL', async () => {
+    await expect(verifier.verify(await mint({ issuer: 'https://other.test/realms/corp' }))).rejects.toThrow(/KEYCLOAK_URL/);
+  });
+
+  it('kid 对不上 JWKS → 拒,话点名 JWKS', async () => {
+    await expect(verifier.verify(await mint({ kid: 'k-unknown' }))).rejects.toThrow(/JWKS/);
+  });
+
+  it('HS256 → 拒(算法写死 RS256)', async () => {
+    const secret = new TextEncoder().encode('0123456789abcdef0123456789abcdef');
+    const token = await new SignJWT({ preferred_username: 'alice' })
+      .setProtectedHeader({ alg: 'HS256', kid: 'k1' })
+      .setSubject('sub-alice')
+      .setIssuer(ISSUER)
+      .setAudience(AUDIENCE)
+      .setExpirationTime(nowSec() + 300)
+      .sign(secret);
+    await expect(verifier.verify(token)).rejects.toThrow(TokenRejectedError);
+  });
+
+  it('alg: none → 拒', async () => {
+    const token = new UnsecuredJWT({ preferred_username: 'alice' })
+      .setSubject('sub-alice')
+      .setIssuer(ISSUER)
+      .setAudience(AUDIENCE)
+      .setExpirationTime(nowSec() + 300)
+      .encode();
+    await expect(verifier.verify(token)).rejects.toThrow(TokenRejectedError);
+  });
+
+  it('缺 preferred_username → 拒,话点名 client scope', async () => {
+    const token = await new SignJWT({ realm_access: { roles: ['user'] } })
+      .setProtectedHeader({ alg: 'RS256', kid: 'k1' })
+      .setSubject('sub-x')
+      .setIssuer(ISSUER)
+      .setAudience(AUDIENCE)
+      .setExpirationTime(nowSec() + 300)
+      .sign(privateKey);
+    await expect(verifier.verify(token)).rejects.toThrow(/preferred_username/);
+  });
+
+  it('拒回的一律是 TokenRejectedError(中间件据此 401)', async () => {
+    await expect(verifier.verify('not-a-jwt')).rejects.toBeInstanceOf(TokenRejectedError);
+  });
+});
diff --git a/apps/api/src/modules/org/index.ts b/apps/api/src/modules/org/index.ts
index 4a7679b..7aaef6b 100644
--- a/apps/api/src/modules/org/index.ts
+++ b/apps/api/src/modules/org/index.ts
@@ -60,3 +60,6 @@ export { identityOf, isNoiseRole, normalizeRoles } from './internal/domain/claim
 export { assertNotLockedOut, endsOf, normalizeEnds } from './internal/domain/ends.ts';
 export { buildInFlightWork } from './internal/domain/in-flight.ts';
 export { DEFAULT_ROLE_ACCESS, NONE_POSITION_CODE, TEST_POSITION_CODE } from './internal/domain/seed-data.ts';
+
+export { createKeycloakTokenVerifier, explainJoseError } from './internal/adapter/keycloak-token-verifier.ts';
+export type { KeycloakVerifierOptions } from './internal/adapter/keycloak-token-verifier.ts';
diff --git a/apps/api/src/modules/org/internal/adapter/keycloak-token-verifier.ts b/apps/api/src/modules/org/internal/adapter/keycloak-token-verifier.ts
new file mode 100644
index 0000000..ba475e3
--- /dev/null
+++ b/apps/api/src/modules/org/internal/adapter/keycloak-token-verifier.ts
@@ -0,0 +1,91 @@
+/**
+ * Keycloak 验签(手册 §4;ADR-012)—— 本地计算,不联网(公钥由 getKey 缓存)。
+ *
+ * 四项校验,顺序即安全要点:`algorithms: ['RS256']` 写死(绝不读 header 的 alg)、
+ * `issuer`、`audience`(本服务 clientId)、`clockTolerance: 30`。
+ * jose 的错误翻成人话(手册 4.4)后包成 TokenRejectedError —— 排错时能省很多时间。
+ */
+import { jwtVerify, errors as joseErrors } from 'jose';
+import type { JWTVerifyGetKey } from 'jose';
+import { z } from 'zod';
+import { TokenRejectedError } from '../../contract.ts';
+import type { TokenVerifier, VerifiedClaims } from '../../port.ts';
+
+export type KeycloakVerifierOptions = {
+  readonly issuer: string;
+  readonly audience: string;
+  /** app 给 `createRemoteJWKSet(certsUrl, {...})`;测试给 `createLocalJWKSet(jwks)` */
+  readonly getKey: JWTVerifyGetKey;
+  /** 秒;缺省 30 */
+  readonly clockTolerance?: number;
+};
+
+const claimsSchema = z.object({
+  sub: z.string().min(1),
+  preferred_username: z.string().min(1),
+  name: z.string().optional(),
+  email: z.string().optional(),
+  realm_access: z.object({ roles: z.array(z.string()).optional() }).optional(),
+});
+
+/**
+ * zod 的 `.optional()` 推出的类型是「键必在、值可为 undefined」,
+ * 而本仓 `exactOptionalPropertyTypes: true` 下 `VerifiedClaims` 的可选字段要求
+ * 「键可不在,但若在则不是 undefined」—— 两边对不上,故显式收窄
+ * (与同目录 `claims.ts` 的 `identityOf` 同一手法:undefined 就不带这个键)。
+ */
+function toVerifiedClaims(claims: z.infer<typeof claimsSchema>): VerifiedClaims {
+  return {
+    sub: claims.sub,
+    preferred_username: claims.preferred_username,
+    ...(claims.name === undefined ? {} : { name: claims.name }),
+    ...(claims.email === undefined ? {} : { email: claims.email }),
+    ...(claims.realm_access === undefined
+      ? {}
+      : { realm_access: claims.realm_access.roles === undefined ? {} : { roles: claims.realm_access.roles } }),
+  };
+}
+
+/** jose 的错误 → 人话(手册 4.4)。JWTExpired 是 JWTClaimValidationFailed 的子类,先判它 */
+export function explainJoseError(error: unknown, ctx: { readonly issuer: string; readonly audience: string }): string {
+  if (error instanceof joseErrors.JWTExpired) return 'token 已过期,用 refresh_token 换个新的';
+  if (error instanceof joseErrors.JWTClaimValidationFailed) {
+    if (error.claim === 'aud') {
+      return `token 的 aud 不含 "${ctx.audience}" —— 去 Keycloak 给发 token 的那个 client 加 audience mapper`;
+    }
+    if (error.claim === 'iss') return `token 的 iss 与 "${ctx.issuer}" 不符 —— 检查 realm 名和 KEYCLOAK_URL`;
+    return `token 的 ${error.claim} 校验未过`;
+  }
+  if (error instanceof joseErrors.JWKSNoMatchingKey) {
+    return 'JWKS 里找不到匹配的公钥 —— token 可能来自别的 realm,或 Keycloak 刚轮换过密钥';
+  }
+  if (error instanceof joseErrors.JWSSignatureVerificationFailed) {
+    return '签名校验失败 —— token 被篡改,或来自另一个 Keycloak 实例';
+  }
+  if (error instanceof joseErrors.JOSEAlgNotAllowed) return 'token 的签名算法不被接受 —— 只认 RS256';
+  if (error instanceof joseErrors.JWSInvalid || error instanceof joseErrors.JWTInvalid) return 'token 格式不合法';
+  return error instanceof Error ? error.message : String(error);
+}
+
+export function createKeycloakTokenVerifier(options: KeycloakVerifierOptions): TokenVerifier {
+  return {
+    async verify(token: string): Promise<VerifiedClaims> {
+      let payload: unknown;
+      try {
+        ({ payload } = await jwtVerify(token, options.getKey, {
+          algorithms: ['RS256'],
+          issuer: options.issuer,
+          audience: options.audience,
+          clockTolerance: options.clockTolerance ?? 30,
+        }));
+      } catch (error) {
+        throw new TokenRejectedError(explainJoseError(error, options));
+      }
+      const parsed = claimsSchema.safeParse(payload);
+      if (!parsed.success) {
+        throw new TokenRejectedError('token 缺少 sub 或 preferred_username —— 检查 Keycloak 的 client scope 是否带 profile');
+      }
+      return toVerifiedClaims(parsed.data);
+    },
+  };
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 518616e..553031b 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -51,6 +51,8 @@ importers:
         specifier: ^3.2.4
         version: 3.2.7(@types/debug@4.1.13)(@types/node@22.20.1)(jsdom@30.0.1)(tsx@4.23.1)(yaml@2.9.0)
 
+  activities/brand-content-toolkit: {}
+
   activities/crm-relationship-coverage: {}
 
   activities/quote-alternative: {}
@@ -94,6 +96,9 @@ importers:
       hono:
         specifier: ^4.12.32
         version: 4.12.32
+      jose:
+        specifier: ^5.10.0
+        version: 5.10.0
       pg:
         specifier: ^8.22.0
         version: 8.22.0
@@ -2591,6 +2596,9 @@ packages:
   jackspeak@3.4.3:
     resolution: {integrity: sha512-OGlZQpz2yfahA/Rd1Y8Cd9SIEsqvXkLVoSw/cgwhnhFMDbsQFeZYoJJ7bIZBS9BcamUW96asq/npPWugM+RQBw==}
 
+  jose@5.10.0:
+    resolution: {integrity: sha512-s+3Al/p9g32Iq+oqXxkW//7jk2Vig6FF1CFqzVXoTUXt2qz89YWbL+OwS17NFYEvxC35n0FKeGO2LGYSxeM2Gg==}
+
   jose@6.2.4:
     resolution: {integrity: sha512-N8acGzVsQy6M/fjFcxtysNc4Q379TcM5dM/qKkNtsHFji88yANnXTr7BLeP75iPnFwBfQzM/jg2BZ9+HZrHCZA==}
 
@@ -6132,6 +6140,8 @@ snapshots:
     optionalDependencies:
       '@pkgjs/parseargs': 0.11.0
 
+  jose@5.10.0: {}
+
   jose@6.2.4: {}
 
   joycon@3.1.1: {}