From 5338bdfc0fe07935c97ac143273e91daf11ba569 Mon Sep 17 00:00:00 2001
From: hailin <hailin.zhao@gdzx.xyz>
Date: Sat, 7 Feb 2026 04:55:54 -0800
Subject: [PATCH] fix(agents): correct Claude API file size limits (image 5MB,
 PDF 25MB)

Claude API enforces a hard 5MB limit per image (not 20MB as previously
set). PDFs have a 32MB total request limit; set individual PDF cap to
25MB to leave room for prompt/messages. The downloadAsBase64 method now
accepts a per-type maxSize parameter.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .../coordinator/coordinator-agent.service.ts     | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/packages/services/conversation-service/src/infrastructure/agents/coordinator/coordinator-agent.service.ts b/packages/services/conversation-service/src/infrastructure/agents/coordinator/coordinator-agent.service.ts
index 507ff16..428dbf4 100644
--- a/packages/services/conversation-service/src/infrastructure/agents/coordinator/coordinator-agent.service.ts
+++ b/packages/services/conversation-service/src/infrastructure/agents/coordinator/coordinator-agent.service.ts
@@ -330,8 +330,10 @@ export class CoordinatorAgentService implements OnModuleInit {
 
   /** 文本类文件最大嵌入大小 (超过则截断) */
   private readonly MAX_TEXT_EMBED_SIZE = 50_000;
-  /** 二进制文件最大 base64 大小 (20MB，Claude API 限制) */
-  private readonly MAX_BINARY_SIZE = 20 * 1024 * 1024;
+  /** 图片最大 5MB（Claude API 硬限制） */
+  private readonly MAX_IMAGE_SIZE = 5 * 1024 * 1024;
+  /** PDF 最大 25MB（Claude API 整个请求 32MB 限制，留 7MB 给 prompt/messages） */
+  private readonly MAX_PDF_SIZE = 25 * 1024 * 1024;
 
   /**
    * 获取 file-service 内部地址
@@ -364,13 +366,13 @@ export class CoordinatorAgentService implements OnModuleInit {
 
       try {
         if (att.type === 'image') {
-          const { base64, mediaType } = await this.downloadAsBase64(contentUrl, att.mimeType);
+          const { base64, mediaType } = await this.downloadAsBase64(contentUrl, att.mimeType, this.MAX_IMAGE_SIZE);
           blocks.push({
             type: 'image',
             source: { type: 'base64', media_type: mediaType, data: base64 },
           });
         } else if (att.mimeType === 'application/pdf') {
-          const { base64 } = await this.downloadAsBase64(contentUrl, att.mimeType);
+          const { base64 } = await this.downloadAsBase64(contentUrl, att.mimeType, this.MAX_PDF_SIZE);
           blocks.push({
             type: 'document',
             source: { type: 'base64', media_type: 'application/pdf', data: base64 },
@@ -405,14 +407,14 @@ export class CoordinatorAgentService implements OnModuleInit {
    * 从内部 URL 下载文件并转为 base64
    * conversation-service 与 file-service 同在 Docker 网络内
    */
-  private async downloadAsBase64(url: string, mimeType: string): Promise<{ base64: string; mediaType: string }> {
+  private async downloadAsBase64(url: string, mimeType: string, maxSize: number): Promise<{ base64: string; mediaType: string }> {
     const response = await fetch(url);
     if (!response.ok) {
       throw new Error(`HTTP ${response.status} from ${url}`);
     }
     const arrayBuffer = await response.arrayBuffer();
-    if (arrayBuffer.byteLength > this.MAX_BINARY_SIZE) {
-      throw new Error(`文件过大 (${(arrayBuffer.byteLength / 1024 / 1024).toFixed(1)}MB)，超过 ${this.MAX_BINARY_SIZE / 1024 / 1024}MB 限制`);
+    if (arrayBuffer.byteLength > maxSize) {
+      throw new Error(`文件过大 (${(arrayBuffer.byteLength / 1024 / 1024).toFixed(1)}MB)，超过 ${(maxSize / 1024 / 1024).toFixed(0)}MB 限制`);
     }
     const base64 = Buffer.from(arrayBuffer).toString('base64');
     return { base64, mediaType: mimeType };