# touchstone-mcp [Health: Active] **Category:** 💰 Finance & Fintech **Repository:** https://github.com/petrkrulis2022/dated-siu-inference **GitHub Stars:** 0 **Views:** 0 **Installs:** 0 **Upvotes:** 0 **Directory Page:** https://allmcps.com/mcp/touchstone-mcp ## Description Dated SIU, the benchmark price of AI inference work: one free tool, three paid via x402. ## Claude Desktop Quick Installation Remote MCP endpoint (confidence: high). Install path detected from listing signals. Add as a URL/SSE server in your client: ```json "mcpServers": { "touchstone-mcp": { "url": "https://testnet.arcscan.app/address/0x12b886b043feabc3d90bbae3ae206d22b208160d" } } ``` ## Documentation & README # Touchstone Assay Touchstone Assay publishes Dated SIU — the benchmark price of AI inference work, measured by actually buying inference against a versioned task basket, not by surveying list prices. ## The two hard invariants 1. **The print is computed from executed runs only.** Published list prices inform exchange rates and are never inputs to the print. 2. **The escrow contract is non-custodial.** Funds move only to the pre-agreed seller, back to the buyer, or to the fee treasury — no admin path to user money exists in any code path. ## How to run a print _Placeholder — wired up once `packages/print` exists._ ## Docs - [`CLAUDE.md`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/CLAUDE.md) — vocabulary, invariants, build boundaries. - [`docs/build1-spec.md`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/docs/build1-spec.md) — the Build 1 engineering specification. - [`docs/plan.md`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/docs/plan.md) — orientation, dependency order, and open risks. - [`docs/architecture.md`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/docs/architecture.md) — one diagram of the whole system. - [`docs/demo.md`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/docs/demo.md) / [`docs/demo-arc.md`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/docs/demo-arc.md) — the buyer/seller agent loop, real transcripts, on Base Sepolia and Arc Testnet. ## Deployments ### Arc Testnet Chain ID `5042002`. Deployed 2026-09-05 from commit `95eea03`. | Contract | Address | Verification | | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------ | --------------- | | `TouchstoneAttestation` | [`0x12b886b043feABc3d90bBae3ae206d22b208160d`](https://testnet.arcscan.app/address/0x12b886b043feabc3d90bbae3ae206d22b208160d) | Pass - Verified | | `TouchstoneEscrow` | [`0x3Cc274d68972DFA1B9B13b90eE40664E0dE2c91F`](https://testnet.arcscan.app/address/0x3cc274d68972dfa1b9b13b90ee40664e0de2c91f) | Pass - Verified | Full record — transaction hashes, block numbers, constructor arguments, compiler settings, and live smoke-test results — is canonical in [`data/deployments/arc-testnet.json`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/data/deployments/arc-testnet.json). **This README section is a convenience view generated from that file** (`node scripts/generate-readme-deployments.mjs`) and must never be hand-edited to disagree with it. **Not deployed to mainnet.** Requirements before it can be: - treasury MUST be a Safe/multisig, not an EOA. It is immutable with no setter, so a lost key makes fee revenue permanently unrecoverable and the only remedy is redeploying the escrow and migrating every integrator. - Generate TOUCHSTONE_PUBLISHER_KEY on an air-gapped machine. The testnet key reused here has passed through repository-adjacent files. - DeployArcTestnet.s.sol is chain-guarded to 5042002; a mainnet deployment needs its own script and its own review. - Arc mainnet's own chain ID and USDC contract address must be independently re-verified against Circle's/Arc's own documentation at deploy time — never copied from this testnet record, even though Arc's testnet USDC happens to sit at a distinctive, memorable address (0x3600...0000). - Arc's public mainnet launches 2026-09-16 — see packages/contracts/script/DeployArcMainnet.s.sol, prepared but not run, with its chain-id guard deliberately left as an env-var placeholder rather than a guessed constant. ### Base Sepolia Chain ID `84532`. Deployed 2026-08-18 from commit `7b1d6ed`. | Contract | Address | Verification | | ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------- | --------------- | | `TouchstoneAttestation` | [`0xF60701793eD168ffd6e818e1DCcb600393297190`](https://base-sepolia.blockscout.com/address/0xF60701793eD168ffd6e818e1DCcb600393297190) | Pass - Verified | | `TouchstoneEscrow` | [`0x3eC06FFe8d5250d5Edf8Fff26b163aaaD65c8a00`](https://base-sepolia.blockscout.com/address/0x3ec06ffe8d5250d5edf8fff26b163aaad65c8a00) | Pass - Verified | Full record — transaction hashes, block numbers, constructor arguments, compiler settings, and live smoke-test results — is canonical in [`data/deployments/base-sepolia.json`](https://github.com/petrkrulis2022/dated-siu-inference/blob/HEAD/data/deployments/base-sepolia.json). **This README section is a convenience view generated from that file** (`node scripts/generate-readme-deployments.mjs`) and must never be hand-edited to disagree with it. **Not deployed to mainnet.** Requirements before it can be: - treasury MUST be a Safe/multisig, not an EOA. It is immutable with no setter, so a lost key makes fee revenue permanently unrecoverable and the only remedy is redeploying the escrow and migrating every integrator. - Generate TOUCHSTONE_PUBLISHER_KEY on an air-gapped machine. The testnet key used here has passed through repository-adjacent files. - Deploy.s.sol is chain-guarded to 84532; a mainnet deployment needs its own script and its own review. ### Verify a print independently A print's own `signature` and `public_key` fields only prove internal consistency — that some key signed this exact body. They cannot prove that key is Touchstone Assay's, because a tampered file could carry a self-consistent signature over a different key entirely. Closing that gap is the entire reason the publisher key is coupled to `TouchstoneAttestation`: the contract's `publisher` address is immutable and lives outside the file, so it is a truth a tampered print cannot rewrite. The loop: 1. Recompute the print's body hash independently (JCS-canonicalise the body minus its signature fields, keccak256 it). 2. Recover the signer's address from the raw `{signature, hash}` pair — not read from the print's own `public_key` field. (Recovery yields two address candidates, since the stored signature carries no recovery bit; exactly one matches a real signer.) 3. Compare the recovered address against `TouchstoneAttestation.publisher()`, read live from chain. 4. Confirm the same body hash is anchored (`postedAt(bodyHash) > 0`). ```bash BASE_SEPOLIA_RPC_URL=... pnpm --filter @touchstone/print run verify-onchain base-sepolia ``` No `TOUCHSTONE_PUBLISHER_KEY` is needed — this command only reads. Real output against the worked-example print (docs/siu-worked-example.md, Dated SIU $0.0383) anchored on Base Sepolia: ``` On-chain publisher(): 0x284ff2F8605Ff8AFeDa6959B856Bb7E6d48f845a Recovered signer candidates: 0x7ab67ceaaf33b21336b0481b3e8a867b70503e35, 0x284ff2f8605ff8afeda6959b856bb7e6d48f845a -> MATCH (recovery id 1): this print was signed by the on-chain publisher. postedAt(bodyHash): 1787035752 -> ANCHORED at 2026-08-18T06:49:12.000Z VERIFIED: signature matches the on-chain publisher AND the hash is anchored. ``` A print signed by any other key — or never anchored at all — reports `NOT VERIFIED` and exits non-zero (verified live against Base Sepolia with an unrelated key: neither recovered candidate matched `publisher()`, and `postedAt` read 0).