Link to the code that reproduces this issue
https://github.com/agentHits/next.js/tree/fix/seo-monolithic-head-metadata
To Reproduce
- Deploy or run an App Router page with asynchronous metadata streaming in Edge SSR runtime.
- Send an HTTP request with User-Agent
TelegramBot (like TwitterBot), ChatGPT-User, GPTBot, or ClaudeBot.
- Read the initial HTML chunk received before the full response streams.
Current vs. Expected behavior
- Current: Metadata tags (
<title>, <meta name="description">, OpenGraph tags) stream in subsequent Suspense chunks. Because HTML-limited bots close the socket after the first chunk, social cards in Telegram and indexing in AI crawlers show empty/missing metadata.
- Expected: Next.js should recognize these user agents and emit a synchronous, monolithic
<head> with all metadata prior to the closing </head> tag.
Provide environment information
Operating System:
Platform: darwin
Arch: arm64
Version: Darwin Kernel Version 24.2.0
Binaries:
Node: 24.21.0
pnpm: 10.33.0
Relevant Packages:
next: 16.4.0-canary.32
react: 19.3.0
react-dom: 19.3.0
Which area(s) are affected? (Select all that apply)
App Router, Edge Runtime (SSR)
Which stage(s) are affected? (Select all that apply)
next start (production mode)
Additional context
Fix verified with failing/passing test in test/e2e/app-dir/metadata-streaming/metadata-streaming.test.ts and test/unit/is-bot.test.ts.
Link to the code that reproduces this issue
https://github.com/agentHits/next.js/tree/fix/seo-monolithic-head-metadata
To Reproduce
TelegramBot (like TwitterBot),ChatGPT-User,GPTBot, orClaudeBot.Current vs. Expected behavior
<title>,<meta name="description">, OpenGraph tags) stream in subsequent Suspense chunks. Because HTML-limited bots close the socket after the first chunk, social cards in Telegram and indexing in AI crawlers show empty/missing metadata.<head>with all metadata prior to the closing</head>tag.Provide environment information
Which area(s) are affected? (Select all that apply)
App Router, Edge Runtime (SSR)
Which stage(s) are affected? (Select all that apply)
next start (production mode)
Additional context
Fix verified with failing/passing test in
test/e2e/app-dir/metadata-streaming/metadata-streaming.test.tsandtest/unit/is-bot.test.ts.