X402 Commerce

Are you building on x402 rails, where buyer agents and seller agents transact in milliseconds? Are seller claims — inventory, price, SLA, identity — still being trusted on plaintext API responses and reputation scores?

Settlement is millisecond-fast. Reputation only delivers post-incident penalties; it does not prevent commits. In a world of ephemeral agents, the counterparty may not even exist by the time the lie is discovered.

• Operators of agent-commerce platforms and marketplaces built on the x402 protocol
• Product leads designing buyer and seller agents in MCP-compatible agent ecosystems
• Digital commerce backbones that need pre-settlement verification on top of Coinbase x402 or the Stripe Agent SDK
• Engineering leads handling fraud, impersonation, and inventory misrepresentation between autonomous agents
• AI governance leads moving from reputation-centric trust to cryptographically-verified trust

Lemma wraps the attributes a seller agent presents — identity, authority, inventory, price, SLA, issuer signature — in ZK proofs. The buyer agent verifies them cryptographically before committing, with no need to trust plaintext claims. Transactions without verifiable proofs stop at the boundary before settlement runs.

x402 carries the settlement rail; Lemma carries the pre-settlement trust rail. The two run in parallel: each agent transaction completes in three stages — pre-settlement verification → x402 settlement → post-settlement cryptographic evidence. Even if an ephemeral seller agent lies, the buyer-side verification rejects it structurally — no reliance on reputation systems.

Where the pre-settlement verification layer fits into your x402 / agent-commerce stack is what we map out in a first conversation.

Tell us how your x402 / agent-commerce stack is wired today, the transaction patterns you anticipate, and the fraud risk you're concerned about. We'll explore together whether Lemma's pre-settlement verification layer could fit. No protocol internals or marketplace data required.

If we see a fit, we move to NDA and then into use-case-specific attribute proof design, reference architecture, and PoC design.

Book a Discovery Call → Download whitepaper

A buyer agent on an agent-commerce marketplace is looking for a specific semiconductor in stock. Over x402, offers come in instantly from several seller agents. One offer claims 1,000 units available at the lowest price with a 48-hour delivery SLA. The buyer commits. x402 settles in milliseconds.

48 hours later, nothing has been delivered. On inquiry, that seller agent has already been retired and there is no accountable principal. The marketplace's reputation system applies a negative score — but the buyer is already out the money. In a world of ephemeral, single-purpose agents, this pattern is structurally unavoidable.

With Lemma in place, the inventory, price, SLA, and identity attributes the seller presents are each wrapped in a ZK proof; the buyer agent verifies them before committing. If the inventory issuer isn't trustworthy, or if the SLA commitment lacks the corresponding authority proof, x402 settlement never runs — execution stops at the boundary.

Use-case-specific design, integration patterns with x402 / Stripe Agent SDK / MCP, and issuance schemas for agent identity proofs are shared in the sector-specific kit we send after the consultation call.

Lemma does not replace the x402 protocol or your existing agent-commerce implementation. We add a single ZK-proof verification gate between the seller's attribute presentation and the buyer's settlement commit.

The seller side issues each attribute as a ZK proof at listing time; the buyer side verifies on receipt. Issuer, validity window, and scope are cryptographically fixed per attribute, so impersonation, inventory misrepresentation, and SLA forgery are structurally caught — never reaching x402 settlement. The post-transaction record persists for both sides as cryptographic evidence in any later dispute.

Integration patterns with x402 / Stripe Agent SDK / MCP, attribute-proof issuance schemas, and embed patterns for marketplace operators are detailed in the whitepaper and the post-call technical kit.

• The issuer signature and validity window of the seller agent's identity, authority, inventory, price, and SLA commitments
• Per-attribute issuer and scope, with independent verification before settlement
• Independence from plaintext claims — the buyer verifies only the attribute proofs
• Cryptographic transaction records on commit, verifiable by third parties in any later dispute

Delegated Treasury

Pillar: P3 Agent Trust Chain

When a buyer agent's spend authority is delegated from an enterprise, the seller can verify not just the seller's attributes — but the buyer's authority to pay. On-chain spend-control attestations complete the trust chain.

→ Delegated Treasury

Multi-Agent Workflows

Pillar: P3 Agent Trust Chain

When an orchestrator agent dispatches a purchasing agent, the delegation chain must be traceable. Lemma proves who authorized the purchase and what scope was delegated at each step.

→ Multi-Agent Workflows