An AI agent buys computing power. It holds no key that can pay.
Warrant lets an AI agent spend USDC inside limits that its owner sets. The agent finds a GPU and proposes a purchase. It cannot make the payment. A small checker program decides. An escrow contract on Arc releases the money, and it accepts only an authorization that it can examine. Prompt injection and a wrong recipient do not pass.
What Warrant is and how it works
An agent that buys from a seller reads text that the seller wrote. A model that reads that text can be tricked. Warrant therefore never lets the model choose where the money goes or how much.
1. Approve
The owner sets the budget cap, the lease length and the approved sellers. A registry signs the wallet address of each seller.
keys the owner approved2. Propose
The agent asks for a quote and proposes a purchase. The agent holds no key that can pay.
a proposal, not a payment3. Decide and pay
The checker evaluates the facts. Only an Allow result produces an authorization. The contract then pays the accepted seller, once, inside the cap.
Allow, Deny or AskFields that select must never come from the text. Fields that quantify can.
The checker signs an authorization. It binds the policy, the recipient, the amount and the order. No other result produces one.
There is no authorization to send. The contract also refuses the payment against live state.
The checker returns its reasons and signs nothing. The buyer decides. Ask is an escalation path, not a failure.
In the mark, the lintel shows the cap of the order. An agent passes through the gate many times. It cannot pass above the lintel. The buyer sets that height one time, when the buyer funds the order.
- Proved
- The rule evaluator agrees with its specification. Allow and Deny hold for every completion of the unknown facts. Verus, 16 obligations, 14 of 14 deliberate bugs rejected
- Tested
- The checker, the signing service and the escrow contracts. The parser and the contracts are tested, not proved.
- Assumed
- Honest registry keys and buyer keys, a standard ERC-20 token and a correct proof verifier.
Showcase: an agent buys GPU time and transcribes audio
The showcase runs on Arc mainnet. A buyer agent rents a one-hour GPU container from our seller. A
faster-whisper worker runs in the container. The agent sends your audio to it and returns
the text with timestamps. A local guardrail holds your wallet key and the spending cap. The agent holds
no key that can pay.
Try it in three steps
- Connect our seller MCP server. Add
https://seller.mnemonik.xyz/mcpto Claude Desktop, Cursor or another MCP client. The server needs no password and no account. Nobody needs to approve you. - Connect the buyer guardrail. This local MCP server holds your Arc wallet key and the 1 USD cap. It funds the escrow and signs your acceptance. The seller cannot do these two steps for you. The guardrail also signs each request with your wallet, so only you can use your container. Buyer setup.
- Ask the agent. Say: "Transcribe audio.mp3." The agent gets a
quote, funds the order, checks the GPU, settles and returns the text. To get audio from a video, run
ffmpeg -i video.mp4 -vn audio.mp3.
What happens on the chain
- Quote. The seller returns a price and a
task_id. A quote moves no money. - Policy check. The guardrail checks the cap and the lease length. It then
funds
TaskEscrow. - Acceptance. The seller reads the order from the chain, accepts it and starts the container on io.net.
- Health check. The agent tests the container. The guardrail signs an acceptance statement.
- Settlement. The checker evaluates the evidence. The escrow releases the USDC to the seller.
- Transcription. The agent posts audio to the worker for the rest of the one-hour lease.
Contracts on Arc mainnet
Chain ID 5042. Every address opens in the Arc explorer. The sources are in the policy-execution repository.
| Contract or key | Address | Role |
|---|---|---|
| TaskEscrow | 0x5fae10ac58bf90c17f516292883a4f17c0768002 | The escrow that the seller MCP uses now. No proof. |
| JournalVerifier | 0xdfe2fdb1d9942af02f99facfaa5b22d0031ad76c | Test double for that escrow. It checks no signature. |
| USDC | 0x3600000000000000000000000000000000000000 | Arc system token, 6 decimals. |
| Seller wallet | 0xb8202bebb6d8a0a822a56c0062632325c3923eeb | Receives the payment for each lease. |
| Registry key | 0x02264b8d8cdb5b5a45736a4e3f679966966f39979b16794f08530c1ac6d77ee034 |
Signs the seller credential. |
| SolverBountyEscrow | 0xbe6b87c0d2a1a7c28207cdecd4f6c68ffe4122e0 | Proven solver canary. Paid only after a Groth16 proof. |
| RiscZeroGroth16Verifier | 0xc4fb7340971e8ad6925f16c2a275cd13cb7bec99 | RISC Zero risc0-ethereum v3.0.0. |
| TaskEscrow (receipt-verified) | 0x9449C1fDd068cDe33D900b1ab15f9861dc39bC51 | Deployed. The seller MCP does not use it yet. |
| ReceiptClaimVerifier | 0x0932F120DEe4cA83676B8224769eE52b7d6D00c6 | Checks the prover signature. Not used yet. |
Transactions on Arc mainnet
A 2 USDC deal settled on 16 October 2026 with a real RISC Zero Groth16 proof. The escrow released the money only after the verifier accepted the proof.
| Step | Transaction |
|---|---|
| Deploy RiscZeroGroth16Verifier | 0xead1e9d7…ee189a |
| Deploy SolverBountyEscrow | 0x34902ab0…121aaa |
| Buyer approves 2 USDC | 0x9c8104d5…db1ac9 |
| Buyer funds the escrow | 0x204eb61a…3d8279 |
| Buyer accepts the proven terms | 0x346fcfc1…8dac9c |
| Settlement with the proof | 0xd0fb5b02…975026 |
| Deploy JournalVerifier | 0x457e62dc…685ade |
| Deploy TaskEscrow (seller MCP) | 0x6adc9771…b14735 |
What to know before you buy
The transcription purchase on mainnet has not run with money yet. You are the first test. The seller MCP settles through the test-double verifier, so you trust the seller. The cap is 1 USD for each deal. The seller gives no hardware attestation. A buyer who funds an order and never settles blocks the single deal slot until the order expires.
Full runbook, how to run your own seller and the operator notes: showcases/ionet_arc. The worker: mnemonik-xyz/transcription.
Join us in a real integration
Our first real-world integration is the purchase of computing power by an AI agent. We invite compute providers, GPU marketplaces, wallet builders and agent builders to integrate Warrant with us and run the first real compute purchases.
Contact us
Ask about the showcase, a pilot or the design. The form opens a message to dev@mnemonik.xyz in your mail program. If no mail program opens, write to that address directly.
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