diff --git a/src/core/condense/__tests__/nested-condense.spec.ts b/src/core/condense/__tests__/nested-condense.spec.ts
index fbccc15ead..39aebc64d5 100644
--- a/src/core/condense/__tests__/nested-condense.spec.ts
+++ b/src/core/condense/__tests__/nested-condense.spec.ts
@@ -1,5 +1,5 @@
 import { describe, it, expect } from "vitest"
-import { ApiMessage } from "../../task-persistence/apiMessages"
+import { LegacyApiMessage } from "../../task-persistence/apiMessages"
 import { getEffectiveApiHistory, getMessagesSinceLastSummary } from "../index"
 
 describe("nested condensing scenarios", () => {
diff --git a/src/core/condense/__tests__/rewind-after-condense.spec.ts b/src/core/condense/__tests__/rewind-after-condense.spec.ts
index b5e8c4c06b..eebb7152fd 100644
--- a/src/core/condense/__tests__/rewind-after-condense.spec.ts
+++ b/src/core/condense/__tests__/rewind-after-condense.spec.ts
@@ -12,7 +12,7 @@
 import { TelemetryService } from "@roo-code/telemetry"
 
 import { getEffectiveApiHistory, cleanupAfterTruncation } from "../index"
-import { ApiMessage } from "../../task-persistence/apiMessages"
+import { LegacyApiMessage } from "../../task-persistence/apiMessages"
 
 describe("Rewind After Condense - Issue #8295", () => {
 	beforeEach(() => {
diff --git a/src/core/message-manager/index.ts b/src/core/message-manager/index.ts
index 71a5f3ae2d..58cc1667dc 100644
--- a/src/core/message-manager/index.ts
+++ b/src/core/message-manager/index.ts
@@ -1,7 +1,7 @@
 import * as path from "path"
 import { Task } from "../task/Task"
 import { ClineMessage } from "@roo-code/types"
-import { ApiMessage } from "../task-persistence/apiMessages"
+import { LegacyApiMessage } from "../task-persistence/apiMessages"
 import { cleanupAfterTruncation } from "../condense"
 import { OutputInterceptor } from "../../integrations/terminal/OutputInterceptor"
 import { getTaskDirectoryPath } from "../../utils/storage"
diff --git a/src/core/task-persistence/__tests__/rooMessages.spec.ts b/src/core/task-persistence/__tests__/rooMessages.spec.ts
index 55f3b7c9c7..dc687dae04 100644
--- a/src/core/task-persistence/__tests__/rooMessages.spec.ts
+++ b/src/core/task-persistence/__tests__/rooMessages.spec.ts
@@ -4,8 +4,8 @@ import * as os from "os"
 import * as path from "path"
 import * as fs from "fs/promises"
 
-import { detectFormat, readRooMessages, saveRooMessages } from "../apiMessages"
-import type { ApiMessage } from "../apiMessages"
+import { detectFormat, readRooMessages, saveRooMessages, stripCacheProviderOptions } from "../apiMessages"
+import type { LegacyApiMessage } from "../apiMessages"
 import type { RooMessage, RooMessageHistory } from "../rooMessage"
 import { ROO_MESSAGE_VERSION } from "../rooMessage"
 import * as safeWriteJsonModule from "../../../utils/safeWriteJson"
@@ -46,7 +46,7 @@ const sampleV2Envelope: RooMessageHistory = {
 	messages: sampleRooMessages,
 }
 
-const sampleLegacyMessages: ApiMessage[] = [
+const sampleLegacyMessages: LegacyApiMessage[] = [
 	{ role: "user", content: "Hello from legacy", ts: 1000 },
 	{ role: "assistant", content: "Legacy response", ts: 2000 },
 ]
@@ -275,3 +275,198 @@ describe("round-trip", () => {
 		expect(detectFormat(parsed)).toBe("v2")
 	})
 })
+
+// ────────────────────────────────────────────────────────────────────────────
+// stripCacheProviderOptions
+// ────────────────────────────────────────────────────────────────────────────
+
+describe("stripCacheProviderOptions", () => {
+	it("returns messages unchanged when they have no providerOptions", () => {
+		const messages: RooMessage[] = [
+			{ role: "user" as const, content: [{ type: "text" as const, text: "hi" }] },
+			{ role: "assistant" as const, content: [{ type: "text" as const, text: "hello" }] },
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual(messages)
+	})
+
+	it("strips anthropic.cacheControl and removes empty providerOptions", () => {
+		const messages: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { cacheControl: { type: "ephemeral" } },
+				},
+			},
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual([
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+			},
+		])
+		expect(result[0]).not.toHaveProperty("providerOptions")
+	})
+
+	it("strips bedrock.cachePoint and removes empty providerOptions", () => {
+		const messages: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					bedrock: { cachePoint: { type: "default" } },
+				},
+			},
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual([
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+			},
+		])
+		expect(result[0]).not.toHaveProperty("providerOptions")
+	})
+
+	it("strips both anthropic.cacheControl and bedrock.cachePoint simultaneously", () => {
+		const messages: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { cacheControl: { type: "ephemeral" } },
+					bedrock: { cachePoint: { type: "default" } },
+				},
+			},
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual([
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+			},
+		])
+		expect(result[0]).not.toHaveProperty("providerOptions")
+	})
+
+	it("preserves anthropic.signature while stripping anthropic.cacheControl", () => {
+		const messages: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { cacheControl: { type: "ephemeral" }, signature: "abc123" },
+				},
+			},
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual([
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { signature: "abc123" },
+				},
+			},
+		])
+	})
+
+	it("preserves openrouter.reasoning_details unchanged", () => {
+		const reasoningDetails = [{ type: "thinking", thinking: "hmm" }]
+		const messages: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					openrouter: { reasoning_details: reasoningDetails },
+				},
+			},
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual([
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					openrouter: { reasoning_details: reasoningDetails },
+				},
+			},
+		])
+	})
+
+	it("strips cache keys while preserving non-cache keys across namespaces", () => {
+		const reasoningDetails = [{ type: "thinking", thinking: "hmm" }]
+		const messages: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { cacheControl: { type: "ephemeral" }, signature: "abc123" },
+					bedrock: { cachePoint: { type: "default" } },
+					openrouter: { reasoning_details: reasoningDetails },
+				},
+			},
+		]
+
+		const result = stripCacheProviderOptions(messages)
+
+		expect(result).toEqual([
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { signature: "abc123" },
+					openrouter: { reasoning_details: reasoningDetails },
+				},
+			},
+		])
+		// bedrock namespace should be fully removed
+		const resultOptions = (result[0] as unknown as Record<string, unknown>).providerOptions as Record<string, unknown>
+		expect(resultOptions).not.toHaveProperty("bedrock")
+	})
+
+	it("does not mutate the original array", () => {
+		const original: RooMessage[] = [
+			{
+				role: "assistant" as const,
+				content: [{ type: "text" as const, text: "hello" }],
+				providerOptions: {
+					anthropic: { cacheControl: { type: "ephemeral" }, signature: "abc123" },
+				},
+			},
+		]
+
+		// Snapshot original state before calling
+		const originalSnapshot = JSON.parse(JSON.stringify(original))
+
+		stripCacheProviderOptions(original)
+
+		expect(original).toEqual(originalSnapshot)
+		// Verify the providerOptions still has cacheControl on the original
+		const originalOptions = (original[0] as unknown as Record<string, unknown>).providerOptions as Record<
+			string,
+			Record<string, unknown>
+		>
+		expect(originalOptions["anthropic"]["cacheControl"]).toEqual({ type: "ephemeral" })
+	})
+
+	it("returns empty array for empty input", () => {
+		const result = stripCacheProviderOptions([])
+
+		expect(result).toEqual([])
+	})
+})
diff --git a/src/core/task-persistence/apiMessages.ts b/src/core/task-persistence/apiMessages.ts
index 3c2149ed44..615d221875 100644
--- a/src/core/task-persistence/apiMessages.ts
+++ b/src/core/task-persistence/apiMessages.ts
@@ -12,7 +12,10 @@ import type { RooMessage, RooMessageHistory } from "./rooMessage"
 import { ROO_MESSAGE_VERSION } from "./rooMessage"
 import { convertAnthropicToRooMessages } from "./converters/anthropicToRoo"
 
-export type ApiMessage = Anthropic.MessageParam & {
+/**
+ * @deprecated This is the legacy Anthropic message format. Use {@link RooMessage} for the current format.
+ */
+export type LegacyApiMessage = Anthropic.MessageParam & {
 	ts?: number
 	isSummary?: boolean
 	id?: string
@@ -40,13 +43,16 @@ export type ApiMessage = Anthropic.MessageParam & {
 	isTruncationMarker?: boolean
 }
 
+/** @deprecated Use {@link LegacyApiMessage} directly. This alias exists for backward compatibility only. */
+export type ApiMessage = LegacyApiMessage
+
 export async function readApiMessages({
 	taskId,
 	globalStoragePath,
 }: {
 	taskId: string
 	globalStoragePath: string
-}): Promise<ApiMessage[]> {
+}): Promise<LegacyApiMessage[]> {
 	const taskDir = await getTaskDirectoryPath(globalStoragePath, taskId)
 	const filePath = path.join(taskDir, GlobalFileNames.apiConversationHistory)
 
@@ -114,7 +120,7 @@ export async function saveApiMessages({
 	taskId,
 	globalStoragePath,
 }: {
-	messages: ApiMessage[]
+	messages: LegacyApiMessage[]
 	taskId: string
 	globalStoragePath: string
 }) {
@@ -194,7 +200,7 @@ export async function readRooMessages({
 			return []
 		}
 
-		return convertAnthropicToRooMessages(parsedData as ApiMessage[])
+		return convertAnthropicToRooMessages(parsedData as LegacyApiMessage[])
 	}
 
 	const primaryResult = await tryParseFile(filePath)
@@ -214,6 +220,48 @@ export async function readRooMessages({
 	return []
 }
 
+/**
+ * Strip transient cache-control provider options that are applied at request
+ * time by applyCacheBreakpoints() and should not be persisted.
+ *
+ * Removes:
+ * - anthropic.cacheControl
+ * - bedrock.cachePoint
+ *
+ * Preserves all other providerOptions (e.g. anthropic.signature, openrouter.reasoning_details).
+ */
+export function stripCacheProviderOptions(messages: RooMessage[]): RooMessage[] {
+	const cloned = structuredClone(messages)
+
+	for (const msg of cloned) {
+		if (!("providerOptions" in msg) || (msg as { providerOptions?: unknown }).providerOptions == null) {
+			continue
+		}
+
+		const providerOptions = (msg as { providerOptions: Record<string, Record<string, unknown>> }).providerOptions
+
+		if (providerOptions["anthropic"] != null) {
+			delete providerOptions["anthropic"]["cacheControl"]
+			if (Object.keys(providerOptions["anthropic"]).length === 0) {
+				delete providerOptions["anthropic"]
+			}
+		}
+
+		if (providerOptions["bedrock"] != null) {
+			delete providerOptions["bedrock"]["cachePoint"]
+			if (Object.keys(providerOptions["bedrock"]).length === 0) {
+				delete providerOptions["bedrock"]
+			}
+		}
+
+		if (Object.keys(providerOptions).length === 0) {
+			delete (msg as { providerOptions?: unknown }).providerOptions
+		}
+	}
+
+	return cloned
+}
+
 /**
  * Save `RooMessage[]` wrapped in the versioned `RooMessageHistory` envelope.
  *
@@ -234,9 +282,10 @@ export async function saveRooMessages({
 	try {
 		const taskDir = await getTaskDirectoryPath(globalStoragePath, taskId)
 		const filePath = path.join(taskDir, GlobalFileNames.apiConversationHistory)
+		const strippedMessages = stripCacheProviderOptions(messages)
 		const envelope: RooMessageHistory = {
 			version: ROO_MESSAGE_VERSION,
-			messages,
+			messages: strippedMessages,
 		}
 		await safeWriteJson(filePath, envelope)
 		return true
diff --git a/src/core/task-persistence/converters/__tests__/anthropicToRoo.spec.ts b/src/core/task-persistence/converters/__tests__/anthropicToRoo.spec.ts
index 8cfc72a9e8..09cae0cb54 100644
--- a/src/core/task-persistence/converters/__tests__/anthropicToRoo.spec.ts
+++ b/src/core/task-persistence/converters/__tests__/anthropicToRoo.spec.ts
@@ -1,4 +1,4 @@
-import type { ApiMessage } from "../../apiMessages"
+import type { LegacyApiMessage } from "../../apiMessages"
 import type {
 	RooUserMessage,
 	RooAssistantMessage,
@@ -16,9 +16,9 @@ import { convertAnthropicToRooMessages } from "../anthropicToRoo"
 // Helpers
 // ────────────────────────────────────────────────────────────────────────────
 
-/** Shorthand to create an ApiMessage with required fields. */
-function apiMsg(overrides: Partial<ApiMessage> & Pick<ApiMessage, "role" | "content">): ApiMessage {
-	return overrides as ApiMessage
+/** Shorthand to create a LegacyApiMessage with required fields. */
+function apiMsg(overrides: Partial<LegacyApiMessage> & Pick<LegacyApiMessage, "role" | "content">): LegacyApiMessage {
+	return overrides as LegacyApiMessage
 }
 
 // ────────────────────────────────────────────────────────────────────────────
@@ -139,7 +139,7 @@ describe("user messages with URL image content", () => {
 
 describe("user messages with tool_result blocks", () => {
 	test("splits tool_result into RooToolMessage before RooUserMessage", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "call_1", name: "read_file", input: { path: "foo.ts" } }],
@@ -179,7 +179,7 @@ describe("user messages with tool_result blocks", () => {
 	})
 
 	test("handles tool_result with array content (joins text with newlines)", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "call_2", name: "list_files", input: {} }],
@@ -204,7 +204,7 @@ describe("user messages with tool_result blocks", () => {
 	})
 
 	test("handles tool_result with undefined content → (empty)", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "call_3", name: "run_command", input: {} }],
@@ -220,7 +220,7 @@ describe("user messages with tool_result blocks", () => {
 	})
 
 	test("handles tool_result with empty string content → (empty)", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "call_4", name: "run_command", input: {} }],
@@ -242,7 +242,7 @@ describe("user messages with tool_result blocks", () => {
 
 describe("user messages with mixed tool_result and text", () => {
 	test("separates tool results from text/image parts correctly", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [
@@ -287,7 +287,7 @@ describe("user messages with mixed tool_result and text", () => {
 	})
 
 	test("only emits tool message when no text/image parts exist", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "tc_only", name: "some_tool", input: {} }],
@@ -733,7 +733,7 @@ describe("metadata preservation", () => {
 	})
 
 	test("carries over metadata on tool messages (split from user)", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "tc_meta", name: "my_tool", input: {} }],
@@ -787,7 +787,7 @@ describe("metadata preservation", () => {
 
 describe("tool name resolution", () => {
 	test("resolves tool names from preceding assistant messages", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "tc_x", name: "execute_command", input: { command: "ls" } }],
@@ -803,7 +803,7 @@ describe("tool name resolution", () => {
 	})
 
 	test("falls back to unknown_tool when tool call ID is not found", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "user",
 				content: [{ type: "tool_result", tool_use_id: "nonexistent_id", content: "result" }],
@@ -815,7 +815,7 @@ describe("tool name resolution", () => {
 	})
 
 	test("resolves tool names across multiple assistant messages", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "tc_first", name: "tool_alpha", input: {} }],
@@ -878,7 +878,7 @@ describe("empty/undefined content edge cases", () => {
 	})
 
 	test("handles tool_result with image content blocks", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			apiMsg({
 				role: "assistant",
 				content: [{ type: "tool_use", id: "tc_img", name: "screenshot", input: {} }],
@@ -914,7 +914,7 @@ describe("empty/undefined content edge cases", () => {
 
 describe("full conversation round-trip", () => {
 	test("converts a realistic multi-turn conversation", () => {
-		const messages: ApiMessage[] = [
+		const messages: LegacyApiMessage[] = [
 			// Turn 1: user asks a question
 			apiMsg({ role: "user", content: "Can you read my config file?", ts: 1000 }),
 			// Turn 2: assistant uses a tool
diff --git a/src/core/task-persistence/converters/anthropicToRoo.ts b/src/core/task-persistence/converters/anthropicToRoo.ts
index 24a0d9bc15..d94c83eb9e 100644
--- a/src/core/task-persistence/converters/anthropicToRoo.ts
+++ b/src/core/task-persistence/converters/anthropicToRoo.ts
@@ -1,5 +1,5 @@
 /**
- * Converter from Anthropic-format `ApiMessage` to the new `RooMessage` format.
+ * Converter from Anthropic-format `LegacyApiMessage` to the new `RooMessage` format.
  *
  * This is the critical backward-compatibility piece that allows old conversation
  * histories stored in Anthropic format to be read and converted to the new format.
@@ -9,7 +9,7 @@
  */
 
 import type { TextPart, ImagePart, ToolCallPart, ToolResultPart, ReasoningPart } from "../rooMessage"
-import type { ApiMessage } from "../apiMessages"
+import type { LegacyApiMessage } from "../apiMessages"
 import type {
 	RooMessage,
 	RooUserMessage,
@@ -28,10 +28,10 @@ import type {
 type LooseProviderOptions = Record<string, Record<string, unknown>>
 
 /**
- * Extract Roo-specific metadata fields from an ApiMessage.
+ * Extract Roo-specific metadata fields from a LegacyApiMessage.
  * Only includes fields that are actually defined (avoids `undefined` keys).
  */
-function extractMetadata(message: ApiMessage): RooMessageMetadata {
+function extractMetadata(message: LegacyApiMessage): RooMessageMetadata {
 	const metadata: RooMessageMetadata = {}
 	if (message.ts !== undefined) metadata.ts = message.ts
 	if (message.condenseId !== undefined) metadata.condenseId = message.condenseId
@@ -82,7 +82,7 @@ function attachReasoningDetails(
 }
 
 /**
- * Convert an array of Anthropic-format `ApiMessage` objects to `RooMessage` format.
+ * Convert an array of Anthropic-format `LegacyApiMessage` objects to `RooMessage` format.
  *
  * Conversion rules:
  * - User string content → `RooUserMessage` with `content: string`
@@ -93,10 +93,10 @@ function attachReasoningDetails(
  * - Standalone reasoning messages → `RooReasoningMessage`
  * - Metadata fields (ts, condenseId, etc.) are preserved on all output messages
  *
- * @param messages - Array of ApiMessage (Anthropic format with metadata)
+ * @param messages - Array of LegacyApiMessage (Anthropic format with metadata)
  * @returns Array of RooMessage objects
  */
-export function convertAnthropicToRooMessages(messages: ApiMessage[]): RooMessage[] {
+export function convertAnthropicToRooMessages(messages: LegacyApiMessage[]): RooMessage[] {
 	const result: RooMessage[] = []
 
 	// First pass: build a map of tool call IDs to tool names from assistant messages.
diff --git a/src/core/task-persistence/index.ts b/src/core/task-persistence/index.ts
index a26fb30de5..4d73d2b0d1 100644
--- a/src/core/task-persistence/index.ts
+++ b/src/core/task-persistence/index.ts
@@ -1,5 +1,5 @@
-export { type ApiMessage, readApiMessages, saveApiMessages } from "./apiMessages"
-export { detectFormat, readRooMessages, saveRooMessages } from "./apiMessages"
+export { type LegacyApiMessage, type ApiMessage, readApiMessages, saveApiMessages } from "./apiMessages"
+export { detectFormat, readRooMessages, saveRooMessages, stripCacheProviderOptions } from "./apiMessages"
 export { readTaskMessages, saveTaskMessages } from "./taskMessages"
 export { taskMetadata } from "./taskMetadata"
 export type { RooMessage, RooMessageHistory, RooMessageMetadata } from "./rooMessage"
diff --git a/src/core/task/Task.ts b/src/core/task/Task.ts
index d03c793095..d1722e9fd6 100644
--- a/src/core/task/Task.ts
+++ b/src/core/task/Task.ts
@@ -110,7 +110,7 @@ import { manageContext, willManageContext } from "../context-management"
 import { ClineProvider } from "../webview/ClineProvider"
 import { MultiSearchReplaceDiffStrategy } from "../diff/strategies/multi-search-replace"
 import {
-	type ApiMessage,
+	type LegacyApiMessage,
 	readApiMessages,
 	saveApiMessages,
 	readTaskMessages,
diff --git a/src/core/webview/__tests__/webviewMessageHandler.edit.spec.ts b/src/core/webview/__tests__/webviewMessageHandler.edit.spec.ts
index 2f11281d2b..f81c71d6e9 100644
--- a/src/core/webview/__tests__/webviewMessageHandler.edit.spec.ts
+++ b/src/core/webview/__tests__/webviewMessageHandler.edit.spec.ts
@@ -40,7 +40,7 @@ vi.mock("../checkpointRestoreHandler", () => ({
 import { webviewMessageHandler } from "../webviewMessageHandler"
 import type { ClineProvider } from "../ClineProvider"
 import type { ClineMessage } from "@roo-code/types"
-import type { ApiMessage } from "../../task-persistence/apiMessages"
+import type { LegacyApiMessage } from "../../task-persistence/apiMessages"
 import { MessageManager } from "../../message-manager"
 
 describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
@@ -54,7 +54,7 @@ describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
 		mockCurrentTask = {
 			taskId: "test-task-id",
 			clineMessages: [] as ClineMessage[],
-			apiConversationHistory: [] as ApiMessage[],
+			apiConversationHistory: [] as LegacyApiMessage[],
 			overwriteClineMessages: vi.fn(),
 			overwriteApiConversationHistory: vi.fn(),
 			handleWebviewAskResponse: vi.fn(),
@@ -126,7 +126,7 @@ describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
 					},
 				],
 			},
-		] as ApiMessage[]
+		] as LegacyApiMessage[]
 
 		// Trigger edit confirmation
 		await webviewMessageHandler(mockClineProvider, {
@@ -184,7 +184,7 @@ describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
 				role: "assistant",
 				content: [{ type: "text", text: "Response" }],
 			},
-		] as ApiMessage[]
+		] as LegacyApiMessage[]
 
 		await webviewMessageHandler(mockClineProvider, {
 			type: "editMessageConfirm",
@@ -244,7 +244,7 @@ describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
 				role: "assistant",
 				content: [{ type: "text", text: "Response" }],
 			},
-		] as ApiMessage[]
+		] as LegacyApiMessage[]
 
 		await webviewMessageHandler(mockClineProvider, {
 			type: "editMessageConfirm",
@@ -282,7 +282,7 @@ describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
 				role: "assistant",
 				content: [{ type: "text", text: "Old message 2" }],
 			},
-		] as ApiMessage[]
+		] as LegacyApiMessage[]
 
 		await webviewMessageHandler(mockClineProvider, {
 			type: "editMessageConfirm",
@@ -378,7 +378,7 @@ describe("webviewMessageHandler - Edit Message with Timestamp Fallback", () => {
 					},
 				],
 			},
-		] as ApiMessage[]
+		] as LegacyApiMessage[]
 
 		// Edit the first user message
 		await webviewMessageHandler(mockClineProvider, {
diff --git a/src/core/webview/webviewMessageHandler.ts b/src/core/webview/webviewMessageHandler.ts
index 041cc72983..0d6288b08c 100644
--- a/src/core/webview/webviewMessageHandler.ts
+++ b/src/core/webview/webviewMessageHandler.ts
@@ -25,7 +25,7 @@ import { customToolRegistry } from "@roo-code/core"
 import { CloudService } from "@roo-code/cloud"
 import { TelemetryService } from "@roo-code/telemetry"
 
-import { type ApiMessage } from "../task-persistence/apiMessages"
+import { type LegacyApiMessage } from "../task-persistence/apiMessages"
 import { saveTaskMessages } from "../task-persistence"
 
 import { ClineProvider } from "./ClineProvider"
@@ -131,11 +131,11 @@ export const webviewMessageHandler = async (
 
 		// Find all matching API messages by timestamp
 		const allApiMatches = currentCline.apiConversationHistory
-			.map((msg: ApiMessage, idx: number) => ({ msg, idx }))
-			.filter(({ msg }: { msg: ApiMessage }) => msg.ts === messageTs)
+			.map((msg: LegacyApiMessage, idx: number) => ({ msg, idx }))
+			.filter(({ msg }: { msg: LegacyApiMessage }) => msg.ts === messageTs)
 
 		// Prefer non-summary message if multiple matches exist (handles timestamp collision after condense)
-		const preferred = allApiMatches.find(({ msg }: { msg: ApiMessage }) => !msg.isSummary) || allApiMatches[0]
+		const preferred = allApiMatches.find(({ msg }: { msg: LegacyApiMessage }) => !msg.isSummary) || allApiMatches[0]
 		const apiConversationHistoryIndex = preferred?.idx ?? -1
 
 		return { messageIndex, apiConversationHistoryIndex }
@@ -148,7 +148,7 @@ export const webviewMessageHandler = async (
 	const findFirstApiIndexAtOrAfter = (ts: number, currentCline: any) => {
 		if (typeof ts !== "number") return -1
 		return currentCline.apiConversationHistory.findIndex(
-			(msg: ApiMessage) => typeof msg?.ts === "number" && (msg.ts as number) >= ts,
+			(msg: LegacyApiMessage) => typeof msg?.ts === "number" && (msg.ts as number) >= ts,
 		)
 	}