diff --git a/cli/src/api/types.ts b/cli/src/api/types.ts
index 142a6397..74f00c92 100644
--- a/cli/src/api/types.ts
+++ b/cli/src/api/types.ts
@@ -1,15 +1,29 @@
-import { AgentStateSchema, MetadataSchema, ModelModeSchema, PermissionModeSchema, TodosSchema } from '@hapi/protocol/schemas'
+import {
+    AgentStateSchema,
+    AttachmentMetadataSchema,
+    MetadataSchema,
+    ModelModeSchema,
+    PermissionModeSchema,
+    TodosSchema
+} from '@hapi/protocol/schemas'
 import type { ModelMode, PermissionMode } from '@hapi/protocol/types'
 import { z } from 'zod'
 import { UsageSchema } from '@/claude/types'
 
 export type Usage = z.infer<typeof UsageSchema>
 
-export type { AgentState, ClaudePermissionMode, CodexPermissionMode, Metadata, Session } from '@hapi/protocol/types'
+export type {
+    AgentState,
+    AttachmentMetadata,
+    ClaudePermissionMode,
+    CodexPermissionMode,
+    Metadata,
+    Session
+} from '@hapi/protocol/types'
 export type SessionPermissionMode = PermissionMode
 export type SessionModelMode = ModelMode
 
-export { AgentStateSchema, MetadataSchema }
+export { AgentStateSchema, AttachmentMetadataSchema, MetadataSchema }
 
 export const MachineMetadataSchema = z.object({
     host: z.string(),
@@ -109,17 +123,6 @@ export const MessageMetaSchema = z.object({
 
 export type MessageMeta = z.infer<typeof MessageMetaSchema>
 
-export const AttachmentMetadataSchema = z.object({
-    id: z.string(),
-    filename: z.string(),
-    mimeType: z.string(),
-    size: z.number(),
-    path: z.string(),
-    previewUrl: z.string().optional()
-})
-
-export type AttachmentMetadata = z.infer<typeof AttachmentMetadataSchema>
-
 export const UserMessageSchema = z.object({
     role: z.literal('user'),
     content: z.object({
diff --git a/server/src/sync/messageService.ts b/server/src/sync/messageService.ts
index 08fab90a..c5bfd316 100644
--- a/server/src/sync/messageService.ts
+++ b/server/src/sync/messageService.ts
@@ -1,17 +1,8 @@
-import type { DecryptedMessage } from '@hapi/protocol/types'
+import type { AttachmentMetadata, DecryptedMessage } from '@hapi/protocol/types'
 import type { Server } from 'socket.io'
 import type { Store } from '../store'
 import { EventPublisher } from './eventPublisher'
 
-type AttachmentMetadata = {
-    id: string
-    filename: string
-    mimeType: string
-    size: number
-    path: string
-    previewUrl?: string
-}
-
 export class MessageService {
     constructor(
         private readonly store: Store,
diff --git a/server/src/web/routes/messages.ts b/server/src/web/routes/messages.ts
index f2f536b2..492298f2 100644
--- a/server/src/web/routes/messages.ts
+++ b/server/src/web/routes/messages.ts
@@ -1,4 +1,5 @@
 import { Hono } from 'hono'
+import { AttachmentMetadataSchema } from '@hapi/protocol/schemas'
 import { z } from 'zod'
 import type { SyncEngine } from '../../sync/syncEngine'
 import type { WebAppEnv } from '../middleware/auth'
@@ -9,19 +10,10 @@ const querySchema = z.object({
     beforeSeq: z.coerce.number().int().min(1).optional()
 })
 
-const attachmentMetadataSchema = z.object({
-    id: z.string(),
-    filename: z.string(),
-    mimeType: z.string(),
-    size: z.number(),
-    path: z.string(),
-    previewUrl: z.string().optional()
-})
-
 const sendMessageBodySchema = z.object({
     text: z.string(),
     localId: z.string().min(1).optional(),
-    attachments: z.array(attachmentMetadataSchema).optional()
+    attachments: z.array(AttachmentMetadataSchema).optional()
 })
 
 export function createMessagesRoutes(getSyncEngine: () => SyncEngine | null): Hono<WebAppEnv> {
diff --git a/shared/src/schemas.ts b/shared/src/schemas.ts
index ead5b5b9..df273f11 100644
--- a/shared/src/schemas.ts
+++ b/shared/src/schemas.ts
@@ -91,6 +91,17 @@ export type TodoItem = z.infer<typeof TodoItemSchema>
 
 export const TodosSchema = z.array(TodoItemSchema)
 
+export const AttachmentMetadataSchema = z.object({
+    id: z.string(),
+    filename: z.string(),
+    mimeType: z.string(),
+    size: z.number(),
+    path: z.string(),
+    previewUrl: z.string().optional()
+})
+
+export type AttachmentMetadata = z.infer<typeof AttachmentMetadataSchema>
+
 export const DecryptedMessageSchema = z.object({
     id: z.string(),
     seq: z.number().nullable(),
diff --git a/shared/src/types.ts b/shared/src/types.ts
index 8aa8d9db..8499d9fe 100644
--- a/shared/src/types.ts
+++ b/shared/src/types.ts
@@ -2,6 +2,7 @@ export type {
     AgentState,
     AgentStateCompletedRequest,
     AgentStateRequest,
+    AttachmentMetadata,
     DecryptedMessage,
     Metadata,
     Session,
diff --git a/web/src/types/api.ts b/web/src/types/api.ts
index c20a552a..3c50f426 100644
--- a/web/src/types/api.ts
+++ b/web/src/types/api.ts
@@ -8,6 +8,7 @@ import type {
 
 export type {
     AgentState,
+    AttachmentMetadata,
     ModelMode,
     PermissionMode,
     Session,
@@ -182,12 +183,3 @@ export type VisibilityPayload = {
 }
 
 export type SyncEvent = ProtocolSyncEvent
-
-export type AttachmentMetadata = {
-    id: string
-    filename: string
-    mimeType: string
-    size: number
-    path: string
-    previewUrl?: string
-}