linkex.ai, documented as an Open Tally instance
linkex.cc documents linkex.ai — a production AI API gateway — as the first implementation of Open Tally, an open protocol for verifiable AI usage accounting.
This site documents linkex.ai as an instance of the Open Tally protocol.
- Open Tally is an open protocol for verifiable AI usage accounting: a set of data formats, cryptographic constructions, and verification procedures that turn a usage ledger into machine-checkable evidence.
- linkex.ai is a production AI API gateway (40+ upstream providers behind one OpenAI-compatible endpoint) and the first production implementation of Open Tally. Every billable AI call it serves — including failed ones — is issued a signed receipt into a publicly verifiable ledger, and that ledger is anchored hourly to Base mainnet.
The product documentation for linkex.ai as a gateway (quickstart, API reference, payments) lives at docs.linkex.ai. This site is about something narrower and deeper: why you don't have to trust linkex.ai's numbers, and how to check them yourself.
The problem, in one sentence
"You say I used 470 million tokens this month and owe you $52,000 — why should I believe you?"
In AI API resale chains, billing is a unilateral claim. Customers can't independently audit the gateway's usage reports; the gateway can't independently ground its disputes with upstream providers. The traditional answer is reputation, spot checks, and contract arbitration.
Open Tally's answer: make the ledger itself non-repudiable, machine-verifiable evidence. Others give you a bill. An Open Tally instance gives you a proof.
What that means, concretely
Right now, with no account and no permission from anyone, you can:
- fetch a signed receipt bundle for any sequenced billing event from
/api/receipt/bundleand verify its signature, its place in the hash chain, and its Merkle inclusion — offline; - fetch the signed period-commitment chain from
/api/receipt/commitmentsand confirm no period was dropped, reissued, or reordered; - open the anchor transparency page and follow any hourly window down to a real transaction on Base — then check that transaction on any public block explorer.
The verification guide walks through each of these with copy-paste commands.
What is Open Tally?
The protocol: signed receipts, hash chains, Merkle commitments, and time anchoring.
The Six Checks
What each verification check proves — and, just as importantly, what it does not.
Verify the ledger
How a customer, supplier, or auditor independently verifies any period, offline.
linkex.ai as the instance
The live deployment: public ledger endpoints, on-chain anchoring on Base, and gateway-side guarantees.
At a glance
| Protocol | Open Tally — verifiable AI usage accounting |
| Instance | linkex.ai (production, live) |
| Receipt signature | Ed25519 over domain-tagged canonical bytes; key history at /api/receipt/keys |
| Canonical form | RFC 8785 canonical JSON with JSON numbers banned — all numerics are decimal strings, all money is int64 micro-USD |
| Ledger structure | Per-channel sequence numbers → hash chain → Merkle period commitments → commitment chain |
| Time anchoring | RFC 3161 timestamps (DigiCert) on every commitment + hourly on-chain anchoring on Base mainnet (eip155:8453), live |
| Public ledger | commitments · keys · bundles · anchor transparency — all eight endpoints |
| Verification | Offline, zero-dependency verifier — six independent checks, each stating what it does not prove |
| Open source | Protocol spec and verification tools publish under opentallyprotocol / @opentally |