diff --git a/packages/experimental/agent-team/README.i18n.yaml b/packages/experimental/agent-team/README.i18n.yaml
index 47dbb4329a..74dbfe69df 100644
--- a/packages/experimental/agent-team/README.i18n.yaml
+++ b/packages/experimental/agent-team/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/experimental/agent-team/README.md
-README.md: 6e2b55018971ec96802de0e5be042d49b45c674a
-README.zh.md: b497d3790e43a9bc843e2a6b88c9755b698034b5
+README.md: 31ea956d2e39dfe25410929be2a574b4c3f07a7d
+README.zh.md: 03344285ceaee965c4154f939f22b592c833840b
diff --git a/packages/experimental/agent-team/README.md b/packages/experimental/agent-team/README.md
index 6e2b550189..31ea956d2e 100644
--- a/packages/experimental/agent-team/README.md
+++ b/packages/experimental/agent-team/README.md
@@ -145,6 +145,8 @@ Tasks are complete versioned snapshots; every mutation carries `expectedRevision
 
 Team events are appended to the exact live Lead Session and flushed before the operation reports success or wakes waiters. `team/member`, `team/task`, `team/message/queued`, and `team/message/delivered` are log-only: they never enter the conversation surface, so derived model history is untouched by coordination records. Session event `seq` and `time` own ordering and timing; snapshots do not duplicate them. The `./invariant` companion replays each candidate Team event against its committed prefix and rejects invalid transitions before append.
 
+Native V4 Team event and checkpoint admission reject retired `tool-result` content before it can enter mailbox state. Historical conversion belongs to the Session-format migration; the Team projection does not convert old wrappers.
+
 ### Disposal
 
 Disposal closes admission, aborts and awaits admitted creation and mailbox-dispatch transactions, then asks the continuation owner to release the roster's exact live direct children and their descendants; non-Team continuable children of the Lead remain untouched. Cleanup failures make disposal fail visibly, bounded by `disposalTimeoutMs`.
diff --git a/packages/experimental/agent-team/README.zh.md b/packages/experimental/agent-team/README.zh.md
index b497d3790e..03344285ce 100644
--- a/packages/experimental/agent-team/README.zh.md
+++ b/packages/experimental/agent-team/README.zh.md
@@ -145,6 +145,8 @@ Lead 可以停止 teammate 的当前轮次，而不会删除其排队的消息
 
 Team 事件追加到精确的 live Lead 会话，并在操作报告成功或唤醒等待者之前 flush。`team/member`、`team/task`、`team/message/queued` 与 `team/message/delivered` 仅存在于日志：它们从不进入会话表面，因此派生模型历史不受协作记录影响。顺序与时间由会话事件的 `seq` 与 `time` 负责，快照不重复保存。`./invariant` 伴生插件把每条候选 Team 事件对照已提交前缀回放，并在 append 前拒绝非法转换。
 
+原生 V4 的 Team 事件及检查点准入会拒绝退役的 `tool-result` 内容，防止它进入邮箱状态。历史转换由 Session 格式迁移负责，Team 投影不转换旧包装。
+
 ### Dispose
 
 dispose 会关闭准入、中止并等待已获准的创建与 mailbox dispatch 事务，再让 continuation owner 释放 roster 中确切的 live direct child 及其后代；Lead 的非 Team continuable child 不受影响。cleanup 失败会让 dispose 明确失败，并以 `disposalTimeoutMs` 为上限。
diff --git a/packages/experimental/agent-team/src/projection.ts b/packages/experimental/agent-team/src/projection.ts
index 85fdfd0e0d..d5dff9784c 100644
--- a/packages/experimental/agent-team/src/projection.ts
+++ b/packages/experimental/agent-team/src/projection.ts
@@ -40,8 +40,8 @@ const imageAttachmentSchema = z.object({
   name: z.string().optional(),
 }).strict()
 
-// ContentBlockMap is merge-extensible. Validate every core variant exactly,
-// while retaining JSON-decoded plugin variants under an unknown type tag.
+// Validate the listed variants; retired tool-result tags cannot enter the
+// merge-extensible fallback for JSON-decoded plugin content.
 const contentBlockSchema: z.ZodType<ContentBlock> = z.lazy(() => z.union([
   z.object({ type: z.literal('text'), text: z.string() }).strict(),
   z.object({ type: z.literal('reasoning'), text: z.string() }).strict(),
@@ -52,12 +52,6 @@ const contentBlockSchema: z.ZodType<ContentBlock> = z.lazy(() => z.union([
     name: z.string(),
     arguments: z.string(),
   }).strict(),
-  z.object({
-    type: z.literal('tool-result'),
-    toolCallId: z.string().min(1),
-    content: z.array(contentBlockSchema),
-    isError: z.boolean().optional(),
-  }).strict(),
   z.object({ type: z.string().min(1) }).loose().refine(
     block => !coreContentBlockTypes.has(block.type),
     { message: 'known content block types must match their declared fields' },
diff --git a/packages/experimental/agent-team/tests/projection-events.spec.ts b/packages/experimental/agent-team/tests/projection-events.spec.ts
index 5f9728a979..e5443d4135 100644
--- a/packages/experimental/agent-team/tests/projection-events.spec.ts
+++ b/packages/experimental/agent-team/tests/projection-events.spec.ts
@@ -1,6 +1,8 @@
-import { describe, expect, it } from 'vitest'
-import { SESSION_FORMAT_VERSION, SessionId, SessionSeq } from '@deepseek-ai/dsh-session'
+import { describe, expect, it, onTestFinished } from 'vitest'
+import { Context } from '@deepseek-ai/cordis'
+import SessionStore, { SESSION_FORMAT_VERSION, SessionId, SessionLogOffset, SessionSeq } from '@deepseek-ai/dsh-session'
 import type { SessionEvent, SessionEventMap, SessionEventType } from '@deepseek-ai/dsh-session'
+import SessionProjectionRegistry from '@deepseek-ai/dsh-session-projection'
 import { teamProjectionDefinition } from '../src/projection.ts'
 import type { TeamProjectionState, TeamState } from '../src/projection.ts'
 import { TeamId, TeamMessageId, TeamTaskId } from '../src/types.ts'
@@ -82,6 +84,28 @@ function message(overrides: Partial<TeamMessageSnapshot> = {}): TeamMessageSnaps
 }
 
 describe('Agent Teams projection events', () => {
+  it('rejects retired tool-result content when restoring a native V4 Team checkpoint', async () => {
+    const ctx = new Context()
+    onTestFinished(() => ctx.fiber.dispose())
+    await ctx.plugin(SessionStore)
+    await ctx.plugin(SessionProjectionRegistry)
+    ctx.effect(() => ctx.sessionProjections.register(teamProjectionDefinition))
+    const session = ctx.sessions.create(ROOT)
+    const restore = (val: unknown) => ctx.sessionProjections.restore({
+      agentTeam: { ver: teamProjectionDefinition.stateVersion, seq: -1, val },
+    }, [], SessionLogOffset(0), session.header, SessionLogOffset(0))
+    const valid = { ...project(ROOT, []), messages: [message()] }
+    expect(restore(JSON.parse(JSON.stringify(valid))).checkpoint['agentTeam']?.val).toEqual(valid)
+    const retiredMessage = message({ content: [{
+      type: 'tool-result', toolCallId: 'retired', content: [{ type: 'text', text: 'old result' }],
+    }] as unknown as TeamMessageSnapshot['content'] })
+    const retired = { ...valid, messages: [retiredMessage] }
+    expect(() => restore(JSON.parse(JSON.stringify(retired)))).toThrow()
+    expect(() => projectTeam(ROOT, [event('team/message/queued', {
+      version: 2, teamId: TEAM, message: retiredMessage,
+    }, SessionSeq(0))])).toThrow(/team\/message\/queued payload is invalid/)
+  })
+
   it('projects current-team records independently from inherited records', () => {
     const records: SessionEvent[] = [
       event('team/member', { version: 2, teamId: TeamId('ancestor'), member: member() }, SessionSeq(0)),