diff --git a/flake.lock b/flake.lock
index 33aae38122b..6aaa22e94ea 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1764290847,
-        "narHash": "sha256-VwPgoDgnd628GdE3KyLqTyPF1WWh0VwT5UoKygoi8sg=",
+        "lastModified": 1764947035,
+        "narHash": "sha256-EYHSjVM4Ox4lvCXUMiKKs2vETUSL5mx+J2FfutM7T9w=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "cd5fedfc384cb98d9fd3827b55f4522f49efda42",
+        "rev": "a672be65651c80d3f592a89b3945466584a22069",
         "type": "github"
       },
       "original": {
diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index 9152fc99bd8..85a41609df9 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -513,6 +513,33 @@ export namespace SessionPrompt {
         })
       }
 
+      // Build messages array for the LLM request
+      const messages: ModelMessage[] = [
+        ...system.map(
+          (x): ModelMessage => ({
+            role: "system",
+            content: x,
+          }),
+        ),
+        ...MessageV2.toModelMessage(
+          msgs.filter((m) => {
+            if (m.info.role !== "assistant" || m.info.error === undefined) {
+              return true
+            }
+            if (
+              MessageV2.AbortedError.isInstance(m.info.error) &&
+              m.parts.some((part) => part.type !== "step-start" && part.type !== "reasoning")
+            ) {
+              return true
+            }
+
+            return false
+          }),
+        ),
+      ]
+
+      await Plugin.trigger("chat.messages.transform", {}, { messages })
+
       const result = await processor.process(() =>
         streamText({
           onError(error) {
@@ -564,29 +591,7 @@ export namespace SessionPrompt {
           stopWhen: stepCountIs(1),
           temperature: params.temperature,
           topP: params.topP,
-          messages: [
-            ...system.map(
-              (x): ModelMessage => ({
-                role: "system",
-                content: x,
-              }),
-            ),
-            ...MessageV2.toModelMessage(
-              msgs.filter((m) => {
-                if (m.info.role !== "assistant" || m.info.error === undefined) {
-                  return true
-                }
-                if (
-                  MessageV2.AbortedError.isInstance(m.info.error) &&
-                  m.parts.some((part) => part.type !== "step-start" && part.type !== "reasoning")
-                ) {
-                  return true
-                }
-
-                return false
-              }),
-            ),
-          ],
+          messages,
           tools: model.info.tool_call === false ? undefined : tools,
           model: wrapLanguageModel({
             model: model.language,
diff --git a/packages/plugin/src/index.ts b/packages/plugin/src/index.ts
index ab7aac251b3..db1e925d04b 100644
--- a/packages/plugin/src/index.ts
+++ b/packages/plugin/src/index.ts
@@ -13,6 +13,7 @@ import type {
 
 import type { BunShell } from "./shell"
 import { type ToolDefinition } from "./tool"
+import { dir } from "console"
 
 export * from "./tool"
 
@@ -169,4 +170,10 @@ export interface Hooks {
       metadata: any
     },
   ) => Promise<void>
+  "chat.messages.transform"?: (
+    input: {},
+    output: {
+      messages: any[]
+    },
+  ) => Promise<void>
 }