The Plain Fetch viewer
In short
The viewer requests a URL the way a plain-fetch agent does: no JavaScript, one request for HTML, one for markdown, one for llms.txt and one for a path that should not exist. It shows the initial HTML on the left, the readable text on the right, and seven flags underneath.
Pre-loaded with www.wikipedia.org, read 4 November 2026. Type any public URL to run your own.
The page answers a plain fetch: 3 of 6 checks found.
Initial HTML what a plain fetch receives
<!doctype html>
<html>
<head>
<title>FastHTML - Modern web applications in pure Python</title>
<link rel="canonical" href="https://fastht.ml/">
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0">
<meta name="description" content="Modern web applications in pure Python">
[... 23 more head elements folded ...]
</head>
<body class="relative bg-black font-geist text-black/80 font-details-off">
<main> <header class="fixed top-0 w-full left-0 p-4 flex items-center justify-center z-50">
<nav class="py-2 px-4 flex justify-between items-center rounded-full w-full max-w-[400px] bg-white/50 backdrop-blur-lg border border-white/20">
<a href="#"><img src="/assets/logo.svg" alt="FastHTML" width="105" height="24"></a><a href="/docs" target="_blank" rel="noopener noreferrer" class="bg-black text-white py-2 px-4 s-body rounded-[62.5rem] hover:bg-black/80 transition-colors duration-300 px-4 py-1 h-10 flex items-center justify-center">Read docs</a> </nav>
</header>
<section class="flex flex-col relative w-full h-screen max-h-[1024px] min-h-[720px] overflow-hidden bg-grey">
<div class="absolute z-0 lg:-top-[15%] top-0 left-1/2 -translate-x-1/2 grid grid-cols-1 grid-rows-1 w-[120%] aspect-square max-w-[2048px] min-w-[900px]">
<svg
width="1224"
height="1224"
viewBox="-100 -100 2124 2124"
fill="none"
xmlns="http://www.w3.org/2000/svg"
class="rotating-shapes w-full h-full"
>[... 3,248 characters folded ...]</svg>
</div>
<div class="flex flex-col flex-1 relative px-4 lg:px-16">
<div class="lg:flex-1 max-lg:basis-[152px]"></div>
<div class="flex-1 flex flex-col items-center justify-center gap-6 text-center w-full text-black">
<h1 class="heading-1 max-w-3xl">Modern web applications in pure Python</h1>
<p class="m-body max-w-[40rem] text-center">Built on solid web foundations, not the latest fads - with
FastHTML you can get started on anything from simple dashboards to
scalable web applications in minutes.</p>
</div>
<div class="flex-1 flex items-center justify-center content-center flex-wrap lg:gap-6 gap-4 m-body">
<a href="https://fastht.ml/about" target="_blank" rel="noopener noreferrer" class="shadow-[inset_0_2px_4px_rgba(255,255,255,0.1),0_4px_8px_rgba(0,0,0,0.5)] m-body px-4 py-1 rounded-full bg-black hover:bg-black/80 transit [... 99 characters folded ...]>Learn more</a><a href="#" id="openVideo" class="shadow-[0_2px_2px_rgba(255,255,255,0.5),0_3px_3px_rgba(0,0,0,0.2)] p-2 rounded-full bg-white hover:bg-white/80 transition-colors duration-300 h-[76px] w-full max-w-[350px] flex items-center gap-4" name="openVideo"><img src="/assets/thumb.png" width="240" height="120" alt="Video poster" class="rounded-full w-[7.5rem] h-auto"><span class="text-black flex flex-col">Watch intro<span class="s-body text-black/60">7min 30sec</span></span> <p class="flex-1 flex items-center">
<img src="/assets/icons/youtube.svg" width="41" height="30" alt="Youtube icon"> </p>
<script>[... 310 characters folded ...]</script></a> <div id="videoOverlay" class="fixed inset-0 bg-black bg-opacity-50 hidden items-center justify-center z-50">
<iframe src="" allowfullscreen allow="autoplay; encrypted-media" id="youtube-player" class="w-full aspect-video" name="youtube-player"></iframe><button id="closeVideo" class="mt-4 bg-soft-pink text-black font-bold py-2 px-4 rounded" name="closeVideo">Close<script>[... 224 characters folded ...]</script></button><script>document.addEventListener('keydown', (e) => { if (e.key === 'Escape') me('#closeVideo').send('click'); });</script> </div>
</div>
<div id="videoPopup" class="hidden fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center">
<div class="bg-white rounded-lg shadow-lg overflow-hidden">
<div class="bg-green-200 p-2 flex justify-between items-center">
<h3 class="text-green-800 font-semibold">Try now</h3>
<button id="closePopup" class="text-green-800 hover:text-green-950" name="closePopup">X</button> </div>
<div class="p-4">
<iframe width="560" height="315" src="" frameborder="0" allowfullscreen="" id="youtubeVideo" name="youtubeVideo"></iframe> </div>
</div>
</div>
</div>
</section>
<section class="relative bg-purple px-4 lg:px-16 pb-24 -mt-8 lg:-mt-10 flex-col xl:items-center items-start gap-6 lg:gap-16 rounded-t-3xl lg:rounded-t-[2.5rem] overflow-x-hidden">
<div class="flex flex-col flex items-center">
<div class="w-full max-w-[50rem] mx-auto flex flex-col flex items-center text-center gap-6">
<h2 class="text-white heading-2 pt-8">This home page is a FastHTML app.</h2>
<p class="text-white pt-8 l-body w-full max-w-[32rem]">Click the buttons below to see four small, live components in action.</p>
</div>
<div aria-labelledby="tab-components" role="tabpanel" id="components-code-demo" class="code-container pt-8 lg:pt-16 tab-panel relative hide-scrollbar toggle-element flex flex-col lg:flex-row lg:justify-between overflow-hidden w-full lg:max-w-[1440px] xl:mx-auto ">
<div class="relative flex flex-col gap-6 lg:max-w-[45rem] w-full overflow-hidden">
<div class="bg-black/20 text-white/80 w-full max-w-2xl lg:max-w-xl p-4 rounded-2xl">
<div class="w-full flex justify-between">
<p class="xs-mono-body flex items-center">card3d.py</p>
<button class="copy-button"> <div class="relative bg-black/20 rounded-[0.5rem] flex items-center p-2 h-8 w-fit">
<img src="assets/icons/copy-icon.svg" alt="Copy" class="button-content w-4 h-4"><span class="absolute bg-inherit rounded-l-[0.5rem] flex items-center py-2 h-full right-0 copied-text overflow-hidden w-0 peer-clicked:w-fit s-body text-white/80 transition-transform transition-all duration-600 ease-out">Copied!</span> </div>
</button> </div>
</div>
<pre id="components-code-snippet" class="code-snippet relative max-h-[25rem] overflow-hidden hide-scrollbar"><code class="python w-full mono-body">def card_3d_demo():
"""This is a standalone isolated Python component.
Behavior and styling is scoped to the component."""
def card_3d(text, background, amt, left_align):
# JS and CSS can be defined inline or in a file
scr = ScriptX('card3d.js', amt=amt)
align='left' if left_align else 'right'
sty = StyleX('card3d.css', background=f'url({background})', align=align)
return Div(text, Div(), sty, scr)
# Design credit: https://codepen.io/markmiro/pen/wbqMPa
card = card_3d("Mouseover me", bgurl, amt=1.5, left_align=True)
return Div(card, style=cardcss)
</code></pre> <div class="absolute code-fade-out bottom-0 left-0 right-0 h-16 bg-gradient-to-b from-transparent to-[#3a2234] pointer-events-none"></div>
</div>
<div class="flex items-center my-11 p-4 flex-none whitespace-normal justify-center h-96 rounded-3xl bg-soft-purple lg:p-8 w-full max-w-2xl lg:max-w-md lg:mx-28 lg:my-8 overflow-y-auto ">
<div style="font-family: 'Arial Black', 'Arial Bold', Gadget, sans-serif; perspective: 1500px;">
<div>
Mouseover me <div></div>
<style>[... 894 characters folded ...]</style>
<script>[... 1,581 characters folded ...]</script> </div>
</div>
</div>
</div>
<div aria-labelledby="tab-dynamic" role="tabpanel" id="dynamic-code-demo" class="code-container pt-8 lg:pt-16 tab-panel relative hide-scrollbar toggle-element flex flex-col lg:flex-row lg:justify-between overflow-hidden w-full lg:max-w-[1440px] xl:mx-auto hidden">
<div class="relative flex flex-col gap-6 lg:max-w-[45rem] w-full overflow-hidden">
<div class="bg-black/20 text-white/80 w-full max-w-2xl lg:max-w-xl p-4 rounded-2xl">
<div class="w-full flex justify-between">
<p class="xs-mono-body flex items-center">weather.py</p>
<button class="copy-button"> <div class="relative bg-black/20 rounded-[0.5rem] flex items-center p-2 h-8 w-fit">
<img src="assets/icons/copy-icon.svg" alt="Copy" class="button-content w-4 h-4"><span class="absolute bg-inherit rounded-l-[0.5rem] flex items-center py-2 h-full right-0 copied-text overflow-hidden w-0 peer-clicked:w-fit s-body text-white/80 transition-transform transition-all duration-600 ease-out">Copied!</span> </div>
</button> </div>
</div>
<pre id="dynamic-code-snippet" class="code-snippet relative max-h-[25rem] overflow-hidden hide-scrollbar"><code class="python w-full mono-body">async def weather_table():
"""Dynamically generated python content
directly incorporated into the HTML"""
# These are actual real-time weather.gov observations
try: results = await all_weather()
except: return P('Weather not available')
rows = [Tr(Td(city), *map(Td, d.values()), cls="even:bg-purple/5")
for city,d in results.items()]
flds = 'City', 'Temp (C)', 'Wind (kmh)', 'Humidity'
head = Thead(*map(Th, flds), cls="bg-purple/10")
return Table(head, *rows, cls="w-full")
</code></pre> <div class="absolute code-fade-out bottom-0 left-0 right-0 h-16 bg-gradient-to-b from-transparent to-[#3a2234] pointer-events-none"></div>
</div>
<div class="flex items-center my-11 p-4 flex-none whitespace-normal justify-center h-96 rounded-3xl bg-soft-purple lg:p-8 w-full max-w-2xl lg:max-w-md lg:mx-28 lg:my-8 overflow-y-auto ">
<table class="w-full">
<thead class="bg-purple/10">
<th>City</th>
<th>Temp (C)</th>
<th>Wind (kmh)</th>
<th>Humidity</th>
</thead>
<tr class="even:bg-purple/5">
<td>New York</td>
<td>11.1</td>
<td>5.4</td>
<td>66.1</td>
</tr>
<tr class="even:bg-purple/5">
<td>San Francisco</td>
<td>NA</td>
<td>NA</td>
<td>NA</td>
</tr>
<tr class="even:bg-purple/5">
<td>Chicago</td>
<td>5</td>
<td>20.4</td>
<td>86.9</td>
</tr>
<tr class="even:bg-purple/5">
<td>Houston</td>
<td>17</td>
Shown with 14 long blocks (scripts, styles, long tags) folded into a marker that says how many characters they hide; the pane stops after the first 200 words; the page is 73 KB.
Reading view the text a plain-fetch client can extract
title: FastHTML - Modern web applications in pure Python
Modern web applications in pure Python
Read docs Modern web applications in pure Python Built on solid web foundations, not the latest fads - with FastHTML you can get started on anything from simple dashboards to scalable web applications in minutes. Learn more Watch intro7min 30sec Close Try now X This home page is a FastHTML app. Click the buttons below to see four small, live components in action. card3d.py Copied! def card_3d_demo(): """This is a standalone isolated Python component. Behavior and styling is scoped to the component.""" def card_3d(text, background, amt, left_align): # JS and CSS can be defined inline or in a file scr = ScriptX('card3d.js', amt=amt) align='left' if left_align else 'right' sty = StyleX('card3d.css', background=f'url({background})', align=align) return Div(text, Div(), sty, scr) # Design credit: https://codepen.io/markmiro/pen/wbqMPa card = card_3d("Mouseover me", bgurl, amt=1.5, left_align=True) return Div(card, style=cardcss) Mouseover me weather.py Copied! async def weather_table(): """Dynamically generated python content directly incorporated into the HTML""" # These are actual real-time weather.gov observations try: results = await all_weather() except: return P('Weather not available') rows = [Tr(Td(city), *map(Td, d.values()), cls="even:bg-purple/5") for city,d in results.items()] flds = 'City', 'Temp (C)', 'Wind (kmh)', 'Humidity' head = Thead(*map(Th, flds), cls="bg-purple/10") return Table(head, *rows, cls="w-full") City Temp (C) Wind (kmh) Humidity New York
996 more words follow in the initial HTML.
| Check | Result | Detail |
|---|---|---|
| H1 in the initial HTML | Found one H1 | First H1: Modern web applications in pure Python |
| First 200 words in the initial HTML | Found 200 of 200 words | The initial HTML carries 1196 words of visible text; the first 200 are marked in the left pane. |
| llms.txt present and linked | Missing absent (404) | /llms.txt returned 404. Absence is not a failure on its own: Ora's lab found it changed nothing for answers already in the HTML. |
| Markdown on request | Missing 200 text/html | Accept: text/markdown returned 200 with text/html; charset=utf-8. The server ignores the header. |
| Status of a made-up path | Found 404 | /agent-ready-html-missing-path-check returned 404: a real status code for a missing page. |
| JSON-LD types | Missing none | No JSON-LD block on the home page. Ora's lab found it made no difference when the answer was already in the HTML; Google says it is not needed for AI features. |
| OpenAPI link | Note none on the home page | No OpenAPI link on the home page. It matters only for a site that ships an API. |
Run the full check
The viewer read one page with four requests. The full check we recommend next is Ora's scan. Its Access layer runs 42 checks worth 30 of its 100 points, among them content without JavaScript, bot detection, llms.txt, markdown on request, JSON-LD and the sitemap (Ora's check catalogue, contract 1.38.0, read 5 November 2026). Open Ora's report for fastht.ml.
Limits: Ora reads public URLs only, says two runs of one scan land within a couple of points without publishing repeat-scan data, and keeps the product that fixes what it finds behind a waitlist. Cloudflare's scanner at isitagentready.com is a quick free alternative, and Mintlify's score covers documentation.
What the viewer does
It sends four plain GET requests with the user agent Mozilla/5.0 (compatible; agent-readiness-crawl/1.0): the URL itself, the same URL with Accept: text/markdown, /llms.txt on the same host, and a made-up path at the root. It runs no JavaScript. The left pane is the first bytes of the HTML as text, with long scripts and styles folded into a marker that says how many characters they hide. The H1 and the first 200 words of visible text are marked in both panes. The flags under the panes say what the four responses added up to.
Limits
- Ten seconds for all four requests together, 1.5 MB read from the home page, at most five redirects, each one checked again.
- http and https only, default ports only. Private, local and internal addresses and names are refused.
- Ten runs per address per minute. The counter lives in memory on the edge function, so it is per instance rather than global. Past ten you get a 429 with a Retry-After header.
- Results are cached for 24 hours by the response headers. Nothing is written to a database: the viewer keeps the first 200 words and the extracted fields for the length of the request and keeps no page body beyond that.
What it does not tell you
A plain fetch from this server is not a real agent. Bot protection weighs the source address more than the user agent, so a page that answers 200 here can still refuse an agent, and the reverse. Ora's lab found (2026-10-19) that returning 403 to agent user agents and hiding the answer in JavaScript were the only two of 19 configurations that stopped retrieval; the viewer can see the second, and can only hint at the first. The initial HTML reference covers both. The server logs and the published crawler address ranges settle the first.
The seven flags
- H1 in the initial HTML
- Whether the HTML the server sends already contains an H1. It is the cheapest sign that the page does not depend on scripts to say what it is.
- First 200 words in the initial HTML
- Whether at least 200 words of visible text arrive in the initial HTML. Under 40 words with an app root element is flagged as a JavaScript shell.
- llms.txt present and linked
- Whether /llms.txt answers with a plain-text file, whether the home page links it (an anchor, a link element or a Link header), and the structure grade the index uses.
- Markdown on request
- Whether a request with Accept: text/markdown comes back as text/markdown. Cloudflare Radar found 3.9 percent of scanned top sites passing this at its April 2026 launch.
- Status of a made-up path
- Whether a path that should not exist returns 404 or 410. A 200 is a soft 404 and reads as a live page.
- JSON-LD types
- The schema.org types found in JSON-LD blocks on the page. Ora's lab found JSON-LD made no difference when the answer was already in the HTML.
- OpenAPI link
- Whether the page links an OpenAPI file, by an anchor or a service-desc link relation. It matters only for a site that ships an API.
Sources
- Ora: AgentReady launch post (Ora's lab findings) https://ora.ai/blog/agentready-launch, read 4 November 2026
- Ora check catalogue, contract 1.38.0 (132 checks, 42 in the Access layer) https://ora.ai/api/checks, read 5 November 2026
- Ora home page (the fixing product is behind a waitlist) https://ora.ai/, read 5 November 2026
- Ora: Introducing Deep Scan (repeat scans) https://ora.ai/blog/introducing-deep-scan, read 5 November 2026
- Ora llms.txt (public URLs only) https://ora.ai/llms.txt, read 5 November 2026
- Vercel: Make your site readable by AI agents https://vercel.com/kb/guide/make-your-site-readable-by-ai-agents, read 4 November 2026
- llms.txt proposal (llmstxt.org) https://llmstxt.org/, read 4 November 2026
Last reviewed 5 November 2026