Title: Umay AI Markdown
Author: Umay Ajans
Published: May 7, 2026
Last modified: May 7, 2026
---
Search plugins
# Umay AI Markdown
By [Umay Ajans](https://profiles.wordpress.org/umayajans/)
[Download](https://downloads.wordpress.org/plugin/markdown-negotiator.1.1.1.zip)
* [Details](https://wordpress.org/plugins/markdown-negotiator/#description)
* [Reviews](https://wordpress.org/plugins/markdown-negotiator/#reviews)
* [Installation](https://wordpress.org/plugins/markdown-negotiator/#installation)
* [Development](https://wordpress.org/plugins/markdown-negotiator/#developers)
[Support](https://wordpress.org/support/plugin/markdown-negotiator/)
## Description
Modern AI agents (ChatGPT, Claude, Perplexity, Gemini, etc.) work much better with
Markdown than HTML. Umay AI Markdown inspects the incoming `Accept` header and,
only when `text/markdown` is requested, intercepts the response and serves a clean,
agent-friendly Markdown representation of the page.
Browsers, search engines, and any client that does not explicitly ask for Markdown
receive the unchanged HTML response. There is no settings page, no cron job, and
no external service call.
**Key features**
* Zero configuration — install, activate, done.
* Only triggers when `Accept: text/markdown` is present. Regular visitors and search
engines are never affected.
* Hybrid content extraction: uses `the_content` for posts/pages, falls back to
a DOM-based extractor for archives, taxonomies, and the homepage.
* Powered by the industry-standard [league/html-to-markdown](https://github.com/thephpleague/html-to-markdown)
library.
* Transient-cached for 12 hours per URL (sha256-keyed). Auto-invalidated on `save_post`,
term edits, theme switches, and menu updates.
* Built-in IP rate limiter (30 requests / minute by default) to mitigate abuse.
* Strict input sanitization, header injection protection, libxml entity hardening(
XXE-safe), and full WordPress Coding Standards compliance.
* PSR-4 autoloaded, namespaced OOP code. No globals.
* Sends `Vary: Accept`, `X-Robots-Tag: noindex`, and `X-Content-Type-Options: nosniff`
on every Markdown response.
**What gets sent to AI agents**
Each Markdown response includes a YAML front-matter block with the page title, site
name, canonical URL, and ISO-8601 generation timestamp, followed by the page body
converted to Markdown. Navigation, footer, sidebars, scripts, styles, comment forms,
related posts, and other page chrome are stripped before conversion.
**Filters**
Two filters are available for advanced customization:
* `umay_mdn_bypass` — Return `true` to skip Markdown handling for the current request.
* `umay_mdn_cache_ttl` — Override the default 12-hour cache lifetime (in seconds,
minimum 60).
* `umay_mdn_rate_limit` — Override the default 30-requests-per-minute rate limit.
* `umay_mdn_converter_options` — Modify the league/html-to-markdown converter options
array.
## Screenshots
* [[
* Markdown response served when an AI agent requests `Accept: text/markdown` —
full HTTP headers (Content-Type, Vary, X-Cache, X-Robots-Tag, X-Content-Type-
Options, X-Markdown-Generator), followed by a YAML frontmatter block (title,
site, URL, generated timestamp) and the converted Markdown body.
* [[
* Built-in transient cache in action: the first request to a URL returns `X-Cache:
MISS` (Markdown generated on the fly), the next request to the same URL returns`
X-Cache: HIT` (served from cache, no rendering work).
* [[
* Transparent content negotiation: same WordPress URL, two different responses
based on the `Accept` request header — browsers receive `text/html` (the normal
theme output), AI agents receive `text/markdown` (clean, machine-readable content)
with the plugin’s enriched header set.
## Installation
1. Upload the `markdown-negotiator` folder (or the ZIP) via **Plugins > Add New >
Upload Plugin**.
2. Activate the plugin.
3. There is no settings page. The plugin starts working immediately.
To verify:
```
curl -H "Accept: text/markdown" https://your-site.com/
```
You should get back a `Content-Type: text/markdown; charset=utf-8` response with
a YAML front-matter and a Markdown body.
## FAQ
### Does it slow down my normal site?
No. The plugin returns immediately on `template_redirect` priority 1 if the request
does not include `Accept: text/markdown`. The cost is roughly a single `if` check
per request.
### Does this plugin contact any external services?
No. The plugin does not call any external service, does not send analytics, does
not check for updates against a remote server, and does not load any remote assets.
All HTML-to-Markdown conversion happens locally using the bundled `league/html-to-
markdown` library.
### How is the cache invalidated?
Per-URL cache keys are deleted on `save_post` and `transition_post_status` for the
affected post. Term edits, theme switches, and menu updates flush the entire Markdown
cache.
### Is logged-in personalization supported?
No. Logged-in requests always fall back to HTML to avoid leaking nonces, admin bars,
or per-user content into a shared Markdown cache. This is by design.
### How do I clear the cache manually?
Deactivate and re-activate the plugin. Deactivation calls `Cache::flush_all()`.
### Is the Markdown response indexable by search engines?
No. Every Markdown response includes `X-Robots-Tag: noindex` to prevent duplicate-
content issues. The HTML version remains the canonical, indexable representation.
### Does this work with caching plugins like LiteSpeed Cache, WP Rocket, or W3 Total Cache?
The plugin sets `Vary: Accept` so any well-behaved cache layer will store the Markdown
and HTML variants separately. If your cache layer ignores the Vary header, exclude
the URLs from the cache when the `Accept: text/markdown` header is present.
## Reviews
There are no reviews for this plugin.
## Contributors & Developers
“Umay AI Markdown” is open source software. The following people have contributed
to this plugin.
Contributors
* [ Umay Ajans ](https://profiles.wordpress.org/umayajans/)
[Translate “Umay AI Markdown” into your language.](https://translate.wordpress.org/projects/wp-plugins/markdown-negotiator)
### Interested in development?
[Browse the code](https://plugins.trac.wordpress.org/browser/markdown-negotiator/),
check out the [SVN repository](https://plugins.svn.wordpress.org/markdown-negotiator/),
or subscribe to the [development log](https://plugins.trac.wordpress.org/log/markdown-negotiator/)
by [RSS](https://plugins.trac.wordpress.org/log/markdown-negotiator/?limit=100&mode=stop_on_copy&format=rss).
## Changelog
#### 1.1.1
* Aligned text domain with WordPress.org plugin slug: changed from `umay-ai-markdown`
to `markdown-negotiator` across plugin header, gettext calls, and POT file (per
WP.org review feedback).
* Hardened Markdown response output: replaced raw `echo $markdown` with `wp_kses(
$markdown, array() )` to satisfy Plugin Check’s late-escape rule while preserving
Markdown syntax.
* Removed bundled tr_TR translation files; only the English POT template ships
in the WordPress.org distribution. Translations now flow through translate.wordpress.
org.
#### 1.1.0
* Renamed plugin: “Markdown Negotiator” “Umay AI Markdown”; slug and text domain
changed to `markdown-negotiator` (per WordPress.org review feedback to ensure
the name is distinctive).
* Removed deprecated `libxml_disable_entity_loader()` calls in `ContentExtractor`
and `Converter`. XXE protection unchanged: libxml 2.9+ disables external entities
by default, and `LIBXML_NONET` is still passed to `loadHTML()`.
* Refactored Tier 2 (non-singular) request pipeline: replaced the open `ob_start(
$callback )` on `template_redirect` with a `template_include` filter that opens
and closes its buffer (`ob_start` paired with `ob_get_clean`) inside a single
function scope, satisfying Plugin Check’s buffer-pairing requirement.
* Added `try/catch` around the template render so a fatal in a theme/plugin returns
a clean 500 instead of a half-buffered response.
#### 1.0.1
* HTML sanitization hardening: strip `