Making My Blog Readable By AI Agents
A lot of the people reading this blog now aren’t people. They’re agents: Claude, ChatGPT, Perplexity and friends, fetching a page because somebody asked them a question. This week I spent an evening making Deallocated Objects nice to read for them (and for search engines while I was in there).
The blog is a static site served by nginx, so everything here is either a file generated at build time or a few lines of nginx config. No framework required.
Markdown For Every Post#
HTML is a lot of noise for an agent to wade through. Every post now also exists as plain markdown. Add `.md` to any post URL:
`https://deallocatedobjects.com/posts/the-art-of-the-reveal.md`
Each file starts with a little YAML frontmatter (title, canonical URL, author, dates, a short description), then the post. The older posts were written in markdown to begin with, so the build just cleans those up and points their images at the self-hosted copies.
The nicer trick is content negotiation. If a client asks for markdown in its `Accept` header, it gets markdown from the _normal_ URL, no `.md` needed. In nginx that’s a `map` plus one line per location:
nginx
```
http context
map $http_accept $deallocated_md { default ""; "~*text/markdown" ".md"; }
server block
location ~ ^/posts/[^/.]+$ { if ($deallocated_md) { rewrite ^ $uri.md last; } try_files $uri.html =404; } ```
Try it:
Shell
`curl -H "Accept: text/markdown" https://deallocatedobjects.com/posts/the-art-of-the-reveal`
Two details matter here. Every response sends `Vary: Accept`, so a cache in the middle never hands HTML to an agent or markdown to a browser. And the `.md` responses send a `Link: <...>; rel="canonical"` header pointing at the HTML page, plus `X-Robots-Tag: noindex`, so Google doesn’t treat them as duplicate copies of every post.
llms.txt#
`/llms.txt` is a plain markdown file at the root of the site that tells an agent what it’s looking at. Mine has a one-line summary of the blog, how to get markdown, where the feeds are, how I’d like posts cited, and a list of every post with a link to its markdown and a one-line summary.
There’s also `/llms-full.txt`, which is the full text of every post in one file (about 225 KB), and `/index.md`, which is the homepage as markdown. Every response also carries a `Link` header pointing at `llms.txt`, so an agent can find it without guessing.
robots.txt#
Silence in `robots.txt` technically means “allowed”, but I’d rather be explicit. Mine allows everyone, then names the big ones explicitly (`GPTBot`, `ClaudeBot`, `PerplexityBot`, `Google-Extended` and about a dozen more) and adds a `Content-Signal` line:
``` User-agent: * Allow: / Content-Signal: search=yes, ai-input=yes, ai-train=yes ```
That’s the right call for a blog. I _want_ to be cited. A product site might choose differently.
Feeds#
The old Atom feed at `/feed` still works, and every entry now has a summary and a `text/markdown` alternate link. I also added a JSON Feed, where each item carries a `_markdown_url` (JSON Feed allows custom keys that start with an underscore).
The old site had almost none of these, so every page got the full set:
- a real meta description, a canonical URL, a robots tag and `lang="en"`
- Open Graph and Twitter card tags, including `article:published_time` and `modified_time`
- JSON-LD structured data: `BlogPosting` and a breadcrumb on every post, with `WebSite`, `Blog` and a `Person` for me on the index pages
The descriptions were sneakier than I expected. The old database stored a pre-made description for each post, but it had run the paragraphs together (“…your app.The RevealWhat do I mean…”) and a few contained raw `<img>` HTML. Now the build makes its summaries from the rendered post text instead.
Two more fixes from the old 2014 markup. The viewport tag had `maximum-scale=1`, which stops people from pinch-zooming on their phones, so that’s gone. And there was no `og:image` at all, so when I shared a post, X and Threads grabbed the first image on the page, which happens to be the Little Bites of Cocoa banner at the top. Every post has a proper 1200x630 preview card now.
IndexNow#
Last, an IndexNow key and a script that pings Bing and friends whenever a post is published. Google doesn’t participate, but Bing’s index feeds a lot of AI search tools, so it’s worth a 30-line script.
None of this took long, and most of it is just files. If you have a blog, `llms.txt` and `.md` versions of your posts are a nice place to start. Here’s this post:
Shell
`curl -H "Accept: text/markdown" https://deallocatedobjects.com/posts/making-my-blog-readable-by-ai-agents` The rest of how this site is built is in the colophon.