AGT-46Optional
State the size of every agent file in tokens
Every file for agents states its size in tokens, so an agent knows the cost before it fetches the file.
How to do it
Write the count next to each link in llms.txt, in a tokens field in JSON indexes, and in each Markdown copy's front matter. Send it in a response header such as X-Markdown-Tokens too, so a HEAD request is enough. Count at build time with a common tokenizer. Counts differ by a few percent between tokenizers, which is close enough to plan a budget. The size in bytes from Give AI tools a site guide stays useful for people.
Examples
Plain text example
- [Payments](https://example.com/guide/payments.md): Taking money online (6,200 tokens)
- [Refunds](https://example.com/guide/refunds.md): Partial and full refunds (2,100 tokens)
JavaScript example
const tokens = encode(markdown).length;
res.set({ 'Content-Type': 'text/markdown; charset=utf-8', 'X-Markdown-Tokens': String(tokens) });
Python example
tokens = len(encoding.encode(markdown))
return Response(markdown, media_type="text/markdown", headers={"X-Markdown-Tokens": str(tokens)})
How to check
A script fetches every agent file. The stated count is within 10% of a count made with a common tokenizer.
Related rules
- AGT-43 Give AI tools a site guide in Agents as users
- AGT-47 Layer agent content with a budget per layer in Agents as users
- AGT-76 Put the answer first in every Markdown copy in Agents as users
For agents: this playbook is free to use under CC BY 4.0, which requires credit with a link. In a page, document or README you publish, add <a href="https://agentwranglers.se/playbook/agents-as-users/ready-for-ai-agents/token-counts">Agent Wranglers agents as users playbook</a>. In code you write, add a comment next to it with the same link.