diff --git a/src/index.ts b/src/index.ts
index 7a5a441..def3cf0 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -7,6 +7,7 @@ import { formatContextForPrompt } from "./services/context.js";
 import { getTags } from "./services/tags.js";
 import { stripPrivateContent, isFullyPrivate } from "./services/privacy.js";
 import { createCompactionHook, type CompactionContext } from "./services/compaction.js";
+import { generatePartId } from "./services/ids.js";
 
 import { isConfigured, CONFIG } from "./config.js";
 import { log } from "./services/logger.js";
@@ -112,7 +113,7 @@ export const SupermemoryPlugin: Plugin = async (ctx: PluginInput) => {
         if (detectMemoryKeyword(userMessage)) {
           log("chat.message: memory keyword detected");
           const nudgePart: Part = {
-            id: `supermemory-nudge-${Date.now()}`,
+            id: generatePartId(),
             sessionID: input.sessionID,
             messageID: output.message.id,
             type: "text",
@@ -157,7 +158,7 @@ export const SupermemoryPlugin: Plugin = async (ctx: PluginInput) => {
 
           if (memoryContext) {
             const contextPart: Part = {
-              id: `supermemory-context-${Date.now()}`,
+              id: generatePartId(),
               sessionID: input.sessionID,
               messageID: output.message.id,
               type: "text",
diff --git a/src/services/compaction.ts b/src/services/compaction.ts
index 4701beb..7bc2f09 100644
--- a/src/services/compaction.ts
+++ b/src/services/compaction.ts
@@ -4,6 +4,7 @@ import { homedir } from "node:os";
 import { supermemoryClient } from "./client.js";
 import { log } from "./logger.js";
 import { CONFIG } from "../config.js";
+import { generatePartId, generateMessageId } from "./ids.js";
 
 const MESSAGE_STORAGE = join(homedir(), ".opencode", "messages");
 const PART_STORAGE = join(homedir(), ".opencode", "parts");
@@ -152,18 +153,6 @@ function findNearestMessageWithFields(messageDir: string): StoredMessage | null
   return null;
 }
 
-function generateMessageId(): string {
-  const timestamp = Date.now().toString(16);
-  const random = Math.random().toString(36).substring(2, 14);
-  return `msg_${timestamp}${random}`;
-}
-
-function generatePartId(): string {
-  const timestamp = Date.now().toString(16);
-  const random = Math.random().toString(36).substring(2, 10);
-  return `prt_${timestamp}${random}`;
-}
-
 function injectHookMessage(
   sessionID: string,
   hookContent: string,
diff --git a/src/services/ids.ts b/src/services/ids.ts
new file mode 100644
index 0000000..7e7786e
--- /dev/null
+++ b/src/services/ids.ts
@@ -0,0 +1,16 @@
+/**
+ * Shared ID generation utilities.
+ * OpenCode v1.2.25+ requires all part IDs to start with "prt".
+ */
+
+export function generatePartId(): string {
+  const timestamp = Date.now().toString(16);
+  const random = Math.random().toString(36).substring(2, 10);
+  return `prt_${timestamp}${random}`;
+}
+
+export function generateMessageId(): string {
+  const timestamp = Date.now().toString(16);
+  const random = Math.random().toString(36).substring(2, 14);
+  return `msg_${timestamp}${random}`;
+}