From 458244112fa2c1c894e6e2feaa46e0e33779c6a2 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Sat, 25 Jul 2026 05:44:48 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Optimize=20agent=20thread?=
 =?UTF-8?q?=20fetching=20with=20getFullThread?=
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The agent currently fetches a thread context by executing an N+1 query: it first fetches all thread message metadata (`stub.getEmails`), then iterates over each one to fetch the full content (`stub.getEmail`). This introduces multiple sequential RPC calls and database reads.

Replaced this with a single call to `getFullThread(stub, threadId)`, which handles the complete retrieval in 2 queries inside the DO instead of N+1. This improves performance when loading agent context for longer threads.

Co-authored-by: schmug <38227427+schmug@users.noreply.github.com>
---
 .jules/bolt.md         |  3 +++
 workers/agent/index.ts | 26 ++++----------------------
 2 files changed, 7 insertions(+), 22 deletions(-)

diff --git a/.jules/bolt.md b/.jules/bolt.md
index d3d39015..480e8263 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -24,3 +24,6 @@
 ## 2026-06-29 - Optimize D1 Queries by Batching
 **Learning:** Found N+1 query pattern on the hub stats page (`hub/src/routes/admin/stats.ts`) when iterating over the list of inbound peers to query `events_pulled_24h` for each peer sequentially using `.first()`. This introduces significant roundtrip latency and resource overhead as the number of peers grows. D1 supports batching queries, which can collapse N queries into a single HTTP roundtrip. D1's returned `batch` types can be peculiar, particularly when running against tests using Miniflare or test shims where row result structure might differ across platforms.
 **Action:** Replaced sequential queries in `Promise.all` with `db.batch()` to combine the multiple `db.prepare(...).bind(...)` calls into a single execution, and normalized the output structure parsing. This significantly reduces N+1 overhead and improves performance scaling as the peer count increases.
+## 2026-07-25 - Avoid N+1 requests in agent thread loading
+**Learning:** Found N+1 query pattern on the `workers/agent/index.ts` file, where `threadEmails.map` iterated to call `stub.getEmail` sequentially which adds overhead to agent context loading.
+**Action:** Replaced loop inside `workers/agent/index.ts` with a single call to `getFullThread(stub, emailData.threadId)`.
diff --git a/workers/agent/index.ts b/workers/agent/index.ts
index a651a819..e8fb1297 100644
--- a/workers/agent/index.ts
+++ b/workers/agent/index.ts
@@ -21,6 +21,7 @@ import {
 	getMailboxStub,
 	stripHtmlToText,
 	textToHtml,
+	getFullThread,
 } from "../lib/email-helpers";
 import { resolveMailboxSettings } from "../lib/mailbox-settings";
 import type { EmailFull, EmailMetadata } from "../lib/schemas";
@@ -433,28 +434,9 @@ export class EmailAgent extends AIChatAgent<any> {
 			}
 
 			// Load thread for conversation context
-			const threadEmails = (await stub.getEmails({
-				thread_id: emailData.threadId,
-			})) as EmailMetadata[];
-			if (threadEmails.length > 1) {
-				const fullThread = await Promise.all(
-					threadEmails.map(async (e) => {
-						const full = (await stub.getEmail(e.id)) as EmailFull | null;
-						const text = full?.body ? stripHtmlToText(full.body) : "";
-						return {
-							id: e.id,
-							sender: e.sender,
-							recipient: e.recipient,
-							subject: e.subject,
-							date: e.date,
-							folder_id: e.folder_id,
-							body_text: text,
-						};
-					}),
-				);
-				// ⚡ Bolt: Optimize sorting by replacing `new Date(b.date).getTime()` with `Date.parse(b.date)`
-				fullThread.sort((a, b) => Date.parse(a.date) - Date.parse(b.date));
-				threadContext = fullThread
+			const threadEmails = await getFullThread(stub, emailData.threadId);
+			if (threadEmails.message_count > 1) {
+				threadContext = threadEmails.messages
 					.map(
 						(e) =>
 							`[${e.date}] ${e.sender} → ${e.recipient} (${e.folder_id}): ${e.body_text.substring(0, 500)}`,