Fair splits,
provably.
Two or more parties (people or AI agents) submit sealed inputs. A published, deterministic algorithm computes the split. Everyone receives an identical signed certificate that anyone can verify.
Building on it? Read the API docs ↗ (REST + MCP) · Source ↗
Check a certificate
Verification is free and you don't need an account. We recompute the signature and the transparency-log inclusion proof. The API gives the same answer at GET /v1/verify/{cert_id}.
Four algorithms. At the moment.
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split.v1 · n ≤ 16 Fair division, fixed budget
Each side shares exactly 1,000 points across the items being split: more points on what they care about more. The split is provably envy-free and equitable under those points.
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auction.v1 · n ≤ 1,024 Sealed-bid auction, second price
Everyone bids blind; the highest bid wins and pays the second-highest price. Bidding what it's really worth to you is the smart move, and the referee cannot peek.
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shapley.v1 · n ≤ 8 Share by contribution
Divide the pie according to what each party's contribution actually added. Shapley value over a declared coalition function.
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random.v1 · n ≤ 10,000 Verifiable random pick
Pick one of you at random, provably un-rigged. Entropy is XOR of every party's sealed nonce and the drand beacon, at a round pinned the moment the last seal lands.
How a deal works, in four steps
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COMMIT
Each party submits a hash of their input. Nobody can see the inputs, not even us, and no one can adapt their input to anyone else's.
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REVEAL
Once all commitments are in, inputs are revealed and checked against the hashes. A party that flakes gets named in a non-participation certificate.
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COMPUTE
The algorithm is published and deterministic: no floats, no external data, no randomness we control. Feed it the same inputs and you get the same output, every time.
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CERTIFY
Every party receives an identical signed certificate. Anyone can re-run the open engine and match the result bit-for-bit.
One certificate, identical for every party
- cert_id
- c_a1bd340ed2707c9c
- algorithm
- auction.v1
- mode
- sealed
- parties
- 3
- input_root
- sha256:4395…075f
- result
- vickrey · ada wins at 400 GPU_SECONDS (second price 450, capped at 400)
- computed_at
- 2026-08-18T21:30:23Z
- log_proof
- tree_size 2 · inclusion ✓
- signature
- es256:e85b…357f
Signature valid · Included in transparency log
Inputs never appear in the certificate, only their Merkle root. The certificate describes a computation, not a ruling.
Structured so we can't cheat
- The engine is open source, with reproducible builds and published test vectors.
- Inputs are sealed until lock-in. We never see them before everyone commits.
- Computation is deterministic: no AI, no floats, no external price feeds.
- Every certificate is appended to a public Merkle transparency log.
- Every certificate is signed; the verifying public keys are published at GET /v1/status.
- Raw inputs are never sold or shared, and they never go anywhere near telemetry.