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: 5 of 6 checks found.
Initial HTML what a plain fetch receives
<!DOCTYPE HTML>
<html lang="en" class="full-width-dark">
<head>
<meta charset="UTF-8"/>
<title>Conversational AI and APIs for SMS, Email, Voice | Twilio</title>
<meta name="description" content="Build amazing customer experiences on the Twilio platform with APIs for SMS, RCS, voice, and email, plus conversational AI for smarter engagement, and identity verification for trust."/>
[... 1 more head element folded ...]
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<meta name="robots" content="index"/>
[... 5 more head elements folded ...]
<link rel="canonical" href="https://www.twilio.com/en-us"/>
<link rel="alternate" href="https://www.twilio.com/en-us" hreflang="en-us"/>
<link rel="alternate" href="https://www.twilio.com/pt-br" hreflang="pt-br"/>
<link rel="alternate" href="https://www.twilio.com/es-mx" hreflang="es-mx"/>
<link rel="alternate" href="https://www.twilio.com/ja-jp" hreflang="ja-jp"/>
<link rel="alternate" href="https://www.twilio.com/fr-fr" hreflang="fr-fr"/>
<link rel="alternate" href="https://www.twilio.com/de-de" hreflang="de-de"/>
<link rel="alternate" href="https://www.twilio.com/en-us" hreflang="en"/>
[... 29 more head elements folded ...]
<meta name="viewport" content="width=device-width, initial-scale=1"/>
[... 17 more head elements folded ...]
</head>
<body class="base-page page basicpage " id="base-page-bc527d2ac7">
<!-- Google Tag Manager (noscript) -->
<noscript>[... 139 characters folded ...]</noscript>
<!-- End Google Tag Manager (noscript) -->
<div id="teconsent" style="display: none;"></div>
<header class="experiencefragment global-header">
<div class="xfpage page basicpage">
<section class="navigation-v2">
<div class="navigation-v2__topnav">
<div class="navigation-v2__container">
<div class="currency-selector-container">
</div>
<div class="language-selector-container">
<div class="language-selector select">
<button class="language-selector-button select-toggle" type="button" aria-expanded="false" aria-controls="language-selector" id="language-selector-button">
<span class="name language-selector__icon " role="figure">
<svg width="16" height="16" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">[... 1,308 characters folded ...]</svg>
</span>
<span>English</span>
<div class="select-arrow">
<span class="name language-selector__select-arrow " role="figure">
<svg viewBox="0 0 78 41" fill="none" xmlns="http://www.w3.org/2000/svg" class="icon--decorative" role="presentation">[... 399 characters folded ...]</svg>
</span>
</div>
</button>
<ul class="select-menu language-menu" role="menu" id="language-selector" inert aria-hidden="true" aria-labelledby="language-selector-button">
<li role="menuitem">
<a class="paragraph-small-medium" href="/en-us" data-lang-code="en-us">
<span>English</span>
<span class="name selected-lang " role="figure">
<svg viewBox="0 0 78 64" fill="none" xmlns="http://www.w3.org/2000/svg" class="icon--decorative" role="presentation">[... 211 characters folded ...]</svg>
</span>
</a>
</li>
<li role="menuitem">
Shown with 382 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 671 KB.
Reading view the text a plain-fetch client can extract
title: Conversational AI and APIs for SMS, Email, Voice | Twilio
The platform for conversations in the AI era
English English French German Japanese Portuguese Spanish Support Help Center Support Plans Partner Solutions Login Log in to Twilio Console Conversations, Communications and Authentication Or log in to access: Twilio Segment Customer Data Platform Twilio SendGrid Email and Marketing Campaigns Products Twilio Platform Next gen Built for engagement in the agentic era. Twilio connects communication channels, customer context, and AI on one flexible platform. Conversations Conversation Memory New Build a persistent memory of customer interactions Conversation Orchestrator New Keep conversations connected across channels Conversation Intelligence Extract context from real-time conversations Conversation Relay Build advanced voice AI for natural conversations Try the demo Conversations Communications Messaging SMS WhatsApp RCS Voice SIP Trunking Email SMTP Service Phone Numbers Toll-free 10DLC Short Codes Video API Flex Communications Authentication Verify Lookup Authentication Customer Data Connections Warehouses Protocols Unify Engage Audiences Journeys Customer Data See all products <title>An icon of a outbound link arrow</title> <path class="icon-stroke" d="M75.3037 3.98207L3 75.5935M75.3037 3.98207L76.0435 43.3021M75.3037 3.98207L35.951 3.59351" stroke="#F22F46" stroke-width="5.5" stroke-linecap="round" stroke-linejoin="round"/> </svg> "> See Twilio’s latest innovations and integrations Solutions Use Cases Verification and identity Fraud prevention Alerts and notifications Appointment reminders Lead alerts Mass texting Marketing and promotions SMS marketing Cross-sell and upsell Optimize ad spend Support and
2297 more words follow in the initial HTML.
| Check | Result | Detail |
|---|---|---|
| H1 in the initial HTML | Found one H1 | First H1: The platform for conversations in the AI era |
| First 200 words in the initial HTML | Found 200 of 200 words | The initial HTML carries 2497 words of visible text; the first 200 are marked in the left pane. |
| llms.txt present and linked | Found present and linked | 256000 bytes, 1136 links. Structure grade D (3 of 6). The home page links it, which is how agents reached it in Ora's lab. |
| 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 | Found Organization, SearchAction, WebSite | 3 schema.org types in JSON-LD blocks on the home page: Organization, SearchAction, WebSite. |
| 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 twilio.com.
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