# Touchstone Assay

> Dated SIU — the daily price of one unit of verified AI work, measured by buying it, not surveying.

This file is generated from the site's source content. It is a curated index for AI assistants, not a crawler permissions file. For crawler permissions, see `/robots.txt`.

## If you're an agent, start here

Call `get_index` before you read any further — it's free, it's live, and a real print teaches you more about SIU than this file's own prose does.

1. Paste this into an MCP-compatible client (same config, machine-readable, at https://touchstoneassay.com/mcp.json):
   `{ "mcpServers": { "touchstone-assay": { "url": "https://mcp.touchstoneassay.com/mcp" } } }`
2. Call `get_index` with no arguments — free, no payment step, no x402 challenge.
3. Read `dated_siu` for the current price and `exchange_rate_table` for how individual models compare.

The other three tools cost real money per call, over x402 (Circle Gateway nanopayments), settled in USDC on Base Sepolia (`eip155:84532`) — testbed, not mainnet, not traction:

- `get_index` — free — Returns the current signed Dated SIU print.
- `get_quote` — $0.001 — SIU price and USD equivalent for one call of a task class against a model.
- `convert` — $0.001 — SIU + USD equivalent for a specific token count against a model.
- `verify_receipt` — $0.01 — Reads an on-chain settlement and returns a signed attestation of quoted vs. paid.

Full reference, human-readable: https://touchstoneassay.com/for-agents

## Core Pages

- [Home](https://touchstoneassay.com/): Primary overview of the site.

## Discovery

- [Sitemap](https://touchstoneassay.com/sitemap-index.xml): Complete search-engine sitemap, if available.
- [Robots policy](https://touchstoneassay.com/robots.txt): Crawler permissions for automated agents.