From d2d7a37bca7febac7df4dd0ecdbc5b1a2d55ef65 Mon Sep 17 00:00:00 2001
From: NatChung <nat.chung1@gmail.com>
Date: Fri, 20 Feb 2026 08:26:29 +0800
Subject: [PATCH] fix: add missing id/sessionID/messageID to MCP tool
 attachments (#14345)

---
 packages/opencode/src/session/prompt.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index f9229de88..75bd3c9df 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -906,7 +906,12 @@ export namespace SessionPrompt {
           title: "",
           metadata,
           output: truncated.content,
-          attachments,
+          attachments: attachments.map((attachment) => ({
+            ...attachment,
+            id: Identifier.ascending("part"),
+            sessionID: ctx.sessionID,
+            messageID: input.processor.message.id,
+          })),
           content: result.content, // directly return content to preserve ordering when outputting to model
         }
       }