Comparison

llms.txt vs ai-agent.json: what and why

llms.txt is a curated content map for LLMs; ai-agent.json is an identity and capability manifest. Different jobs — you need both.

In short

These are not competitors: llms.txt tells an LLM what content to read, while ai-agent.json says who you are and what you can do as a service. Do both.

What each is

  • llms.txt — a Markdown file at /llms.txt with curated links to key pages. Helps a model find important content within a limited context.
  • ai-agent.json — a JSON manifest at /.well-known/ai-agent.json: name, description, capabilities, endpoints. The service’s “business card” for an integrating agent.

Side by side

llms.txtai-agent.json
FormatMarkdownJSON
Path/llms.txt/.well-known/ai-agent.json
AudienceAn LLM reading contentAn agent integrating
Answers”What’s there to read?""Who are you and what can you do?”

Key difference

llms.txt is about content (articles, docs); ai-agent.json is about interaction (capabilities, API, payments). The first leads a model to text; the second describes how to work with you programmatically.

Do both

Yes — they complement each other: llms.txt brings an LLM to the right content, and ai-agent.json explains how to integrate with your service (including payment protocols via the payments field).

How to verify

A free scan checks both files (presence, format, required fields) in one report.