From 9d742ba51f01281b95e9fd10a3fcd4c3654b68cf Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Sat, 24 Jan 2026 13:52:27 +0000
Subject: [PATCH] fix: hide message_id hints in web chat

---
 src/gateway/chat-sanitize.test.ts | 42 +++++++++++++++++++++++++++++++
 src/gateway/chat-sanitize.ts      | 15 ++++++++---
 2 files changed, 54 insertions(+), 3 deletions(-)
 create mode 100644 src/gateway/chat-sanitize.test.ts

diff --git a/src/gateway/chat-sanitize.test.ts b/src/gateway/chat-sanitize.test.ts
new file mode 100644
index 000000000..29c3f3e9a
--- /dev/null
+++ b/src/gateway/chat-sanitize.test.ts
@@ -0,0 +1,42 @@
+import { describe, expect, test } from "vitest";
+import { stripEnvelopeFromMessage } from "./chat-sanitize.js";
+
+describe("stripEnvelopeFromMessage", () => {
+  test("removes message_id hint lines from user messages", () => {
+    const input = {
+      role: "user",
+      content: "[WhatsApp 2026-01-24 13:36] yolo\n[message_id: 7b8b]",
+    };
+    const result = stripEnvelopeFromMessage(input) as { content?: string };
+    expect(result.content).toBe("yolo");
+  });
+
+  test("removes message_id hint lines from text content arrays", () => {
+    const input = {
+      role: "user",
+      content: [{ type: "text", text: "hi\n[message_id: abc123]" }],
+    };
+    const result = stripEnvelopeFromMessage(input) as {
+      content?: Array<{ type: string; text?: string }>;
+    };
+    expect(result.content?.[0]?.text).toBe("hi");
+  });
+
+  test("does not strip inline message_id text that is part of a line", () => {
+    const input = {
+      role: "user",
+      content: "I typed [message_id: 123] on purpose",
+    };
+    const result = stripEnvelopeFromMessage(input) as { content?: string };
+    expect(result.content).toBe("I typed [message_id: 123] on purpose");
+  });
+
+  test("does not strip assistant messages", () => {
+    const input = {
+      role: "assistant",
+      content: "note\n[message_id: 123]",
+    };
+    const result = stripEnvelopeFromMessage(input) as { content?: string };
+    expect(result.content).toBe("note\n[message_id: 123]");
+  });
+});
diff --git a/src/gateway/chat-sanitize.ts b/src/gateway/chat-sanitize.ts
index 398fabf1f..c4bded4fc 100644
--- a/src/gateway/chat-sanitize.ts
+++ b/src/gateway/chat-sanitize.ts
@@ -14,6 +14,8 @@ const ENVELOPE_CHANNELS = [
   "BlueBubbles",
 ];
 
+const MESSAGE_ID_LINE = /^\s*\[message_id:\s*[^\]]+\]\s*$/i;
+
 function looksLikeEnvelopeHeader(header: string): boolean {
   if (/\d{4}-\d{2}-\d{2}T\d{2}:\d{2}Z\b/.test(header)) return true;
   if (/\d{4}-\d{2}-\d{2} \d{2}:\d{2}\b/.test(header)) return true;
@@ -28,13 +30,20 @@ export function stripEnvelope(text: string): string {
   return text.slice(match[0].length);
 }
 
+function stripMessageIdHints(text: string): string {
+  if (!text.includes("[message_id:")) return text;
+  const lines = text.split(/\r?\n/);
+  const filtered = lines.filter((line) => !MESSAGE_ID_LINE.test(line));
+  return filtered.length === lines.length ? text : filtered.join("\n");
+}
+
 function stripEnvelopeFromContent(content: unknown[]): { content: unknown[]; changed: boolean } {
   let changed = false;
   const next = content.map((item) => {
     if (!item || typeof item !== "object") return item;
     const entry = item as Record<string, unknown>;
     if (entry.type !== "text" || typeof entry.text !== "string") return item;
-    const stripped = stripEnvelope(entry.text);
+    const stripped = stripMessageIdHints(stripEnvelope(entry.text));
     if (stripped === entry.text) return item;
     changed = true;
     return {
@@ -55,7 +64,7 @@ export function stripEnvelopeFromMessage(message: unknown): unknown {
   const next: Record<string, unknown> = { ...entry };
 
   if (typeof entry.content === "string") {
-    const stripped = stripEnvelope(entry.content);
+    const stripped = stripMessageIdHints(stripEnvelope(entry.content));
     if (stripped !== entry.content) {
       next.content = stripped;
       changed = true;
@@ -67,7 +76,7 @@ export function stripEnvelopeFromMessage(message: unknown): unknown {
       changed = true;
     }
   } else if (typeof entry.text === "string") {
-    const stripped = stripEnvelope(entry.text);
+    const stripped = stripMessageIdHints(stripEnvelope(entry.text));
     if (stripped !== entry.text) {
       next.text = stripped;
       changed = true;