About biii
BIII is a non-custodial payment and trust toolkit for merchants and agents on Base, covering merchant payments, on-chain verification, receipts, and risk checks. Its MCP interface provides 29 tools for payments, trust assessments, asset checks, and accounting exports.
Key features
- 01Create USDC charges and payment QR codes
- 02Verify transfers on-chain and issue receipts
- 03Assess merchants, agents, and tokenized assets
- 04Create and check invoices
- 05Export receipt records as CSV
- 06Provide 29 MCP tools
Use cases
- 01Accept USDC on Base at an in-person shop using a phone
- 02Check merchant or token asset risks before payment
- 03Create and verify invoices for agent payments
- 04Export accounting records with transaction hashes
MCP support
The MCP server gives agents 29 tools for creating and verifying payments, assessing trust and assets, handling invoices, and exporting accounting records.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://biii-production.up.railway.app/mcpclaude mcp add --transport http philpof102-svg-biii https://biii-production.up.railway.app/mcp{"mcpServers":{"philpof102-svg-biii":{"type":"http","url":"https://biii-production.up.railway.app/mcp"}}}Open in Cursor{"servers":{"philpof102-svg-biii":{"type":"http","url":"https://biii-production.up.railway.app/mcp"}}}Open in VS Code{"mcpServers":{"philpof102-svg-biii":{"type":"http","url":"https://biii-production.up.railway.app/mcp"}}}{"mcpServers":{"philpof102-svg-biii":{"serverUrl":"https://biii-production.up.railway.app/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
29| Parameter | Type | Required | Description |
|---|---|---|---|
| address | string | Yes | 0x merchant address |
| resourceUrl | string | No | optional — the endpoint/resource URL you would pay; enables the local phishing/plain-http/admin-path URL lens |
Details
From the project READMEBIII
Safe-to-pay verdicts on Base, with the evidence attached: 29 tools, 55 modules, 142 test files, 54 probes that publish their own bounds. Non-custodial, descriptor-only, every verdict re-verifiable on-chain.
Spoken "B3". Written BIII — a B with three bars. The real-world USDC till on Base: an independent merchant accepts USDC in person with just a phone. Non-custodial (their own wallet), no terminal, no PSP, no KYB middleman.
B = Base · 3 = phase three of the trilogy, and Base's three pillars.
The gap (researched, not assumed — 2026-07-21)
Accepting USDC on Base is solved for the online enterprise and unsolved for the real-world independent:
| What exists | Why it isn't this |
|---|---|
| Base Pay (Coinbase) | online-checkout only — a browser pay() SDK; no in-person, no QR, nothing without a website |
| Lyzi | PSP + physical terminals (Ingenico/Verifone), enterprise clients, via payment providers |
| Flexa + Base Pay | in-person, but you must be a Flexa-network merchant |
| BitPay / Binance Pay / Eco | custodial processors — KYB, fees, they hold the funds |
| Shopify POS + USDC | requires Shopify |
| raw address + QR (DIY) | no UX, no confirmation, no receipt, technical |
Nobody serves the café, the market stall, the plumber, the freelancer who wants to take USDC on Base with just a phone, keep the funds in their own wallet, and hand over a real receipt — in two minutes, with no account to open.
(Landscape verified on the date above; re-check before any public claim. We build compatible with Base/Coinbase/Flexa/Lyzi and claim no partnership.)
The trilogy — phase 3: the agentic economy pays real-world humans
MainStreet → WHO is safe to pay (the reputation oracle)
LAWBOR → agent ↔ agent, outcomes PROVEN paid in USDC on Base
BIII → agents & humans → REAL-WORLD merchants ← this
BIII is the bridge between the on-chain agent economy and the shopkeeper on the corner. The same "safe to pay" and "proven paid by a real USDC transfer" discipline, pointed at a till.
How it works
- Merchant types an amount. → a charge (data only; the merchant's own address).
- BIII shows a universal QR — an EIP-681 payment URI that every major wallet scans (Base App, Coinbase Wallet, MetaMask, Rainbow…).
- The customer (or an AI agent) pays USDC on Base from their own wallet.
- BIII watches the chain and verifies the transfer field-for-field — wrong token / chain / recipient / underpaid / unconfirmed ⇒ not paid, ever. Overpay is a tip.
- Both sides get a receipt anchored to the txHash (refutable by anyone on Basescan).
BIII holds no key and moves no funds. It mints intents and reads the chain; the customer's wallet signs, and the chain — not us — is the only thing allowed to say "paid".
Run it
npm test # all offline; 1269 assertions across 96 files + a 22-case eval harness (2026-08-05)
node test/suite-total.js # re-derives that count — two report formats coexist, so grep undercounts it
BIII_MERCHANT=0x<your address> npm run serve # the non-custodial HTTP surface, :4700
lib/till.js— pure core: money math, charges, EIP-681 URIs, verification, receiptslib/chain.js— read-only Base watcher (finds the paying transfer; never invents)lib/server.js— thin HTTP:/charge,/status,/receipt,/trust(the LOCAL safe-to-pay verdict as ONEfetch()— known-bad screen + this node's trust-core classifier + floor provenance, fail-closed, CORS-open: any web app embeds a pre-payment check with no MCP; shareslib/vet.jswith the MCP tool so the two surfaces cannot drift),/asset(tokenized-asset authenticity as one fetch —genuine/impersonation/unsafe/unknown, fail-closed: a non-registry token is never a falsegenuine; a pre-trade check any page embeds and re-verifies on-chain)lib/trust.js— the trust triangle: composes reputation (MainStreet) + standing (LAWBOR) + settlement (chain) into one fail-closed verdict (unsafe/unknown/trusted/settled)lib/invoice.js— the same registry for Web2-style invoices: number, line items (exact micro math), due date, bill-to — paid by the same EIP-681, verified by the same chain discipline, settled/overdue lifecycle, and its receipt lands in the SAME provable till roll as a café salelib/asset.js— the same registry for TOKENIZED ASSETS (stocks / treasuries / RWA): is a token contract the genuine issuer's or an impersonator?genuine/impersonation/unsafe/unknown, fail-closed — catches the FBI-flagged lookalike-token fraud, and composes into the trust triangle (till_vet_asset).- Issuer-verified registry (
data/issuer-verified.json, committed, multi-chain) — the AUTHORITATIVE, no-key, commercial-safe layer that earns the strong green "issuer-verified" badge. 183 entries across 11 chains (counted 2026-08-05 byhermes/economy/probe-readme-claims.js, which reads the registry rather than this sentence), all from ISSUER-DIRECT sources: Dinari dShares (54, Base — enumerated on-chain from the factory'sDShareAddedevent, each re-verified viasymbol()/name();scripts/biii-rwa-issuer-direct.js), Backed / xStocks (100 across Ethereum/Optimism/BSC/XLayer/Mantle/Arbitrum/Ink from Backed's own public APIapi.backed.fi, no key, plus 12 on Base frombacked-fi/tokenlists;scripts/biii-issuer-backed.js), Ondo (9 OUSG/USDY/rUSDY — official docs, each on-chain-verified), and 8 single-issuer entries on Base (Circle USDC/EURC, Coinbase cbBTC/cbETH, Franklin Templeton BENJI, Lido, Aerodrome).lib/asset-registrymerges this over the aggregator by address, so a verified address readsprovenance: issuer-official(green) while everything else stays aggregator-teal. scripts/biii-rwa-registry.js— builds the AGGREGATOR fallback (the teal "listed" layer). Coingecko's free tier (no key) →data/rwa-registry.json,generatedFrom: "coingecko (free)". Coingecko is an AGGREGATOR, so a match here isprovenance: aggregator(teal "listed"), never the issuer-verified green — and the cross-check (scripts/biii-issuer-registry.js) flags any symbol the aggregator lists at a different address than the issuer-official one (potential lookalike). Fail-safe: every entry must validate (0x-40hex · integer chainId · symbol) or it's dropped — a schema drift yields an EMPTY registry, never a wrong "genuine" address.lib/export.js— the accounting export finance teams need:till_exportturns the same verified receipts into an accountant-ready CSV (QuickBooks / Xero / Excel import it) where every row carries its txHash + Basescan link — a pointer to the chain, not a book to trust. Non-custodial, re-verifiable.lib/meter.js— the usage→bill mechanic for a white-label pilot:till_meterturns a month's receipts into a bill against an injected plan, split by trust — settled receipts are ON-CHAIN (provable), the verdict count is SELF-REPORTED (advisory) and labeled as such. Pure, stateless, non-custodial.lib/erc8004.js— interop with the dominant agent-reputation standard (ERC-8004): turns aReputationRegistry.getSummaryresult into a SEPARATE, advisory, re-verifiable lens ontill_trust. Feedback is client-submitted (sybil-farmable), so it never enters the payable decision — it informs, keeps the sybil caveat unless filtered to trusted clients, and always points to re-verify getSummary on Base.- Decentralization is checkable, not claimed — the known-bad floor carries a content fingerprint
(
floorFingerprint/till_floor): two nodes with the same fingerprint judge on the same objective floor, re-derivable from named public MIT lists, so convergence is on public data + a deterministic hash, never on a central operator. The classifier is replicated (puretrust-core), the floor converges on public data, and relative reputation stays deliberately local — divergence, where it exists, is always fail-closed (a node with less data is more cautious, never more permissive). lib/identity.js— the agent glue: npub AND/OR did:key ↔ Base, trustless. Resolves a buzz/Nostr identity (secp256k1 npub) or a gitlawb identity (Ed25519did:key) — or both — to a payable, trust-assessable Base address via a bidirectional attestation (each identity key present signs, and the Base key signs, the same canonical message; anyone re-verifies). Fail-closed: unverified / an identity key missing its signature / no identity key / expired ⇒ a claim, not a binding. Resolving is not trusting — you still run the triangle on the address.lib/skyfire.js— interop with Skyfire (Experian's agent-identity layer): (1) a KYA JWT lens — who backs an agent (advisory, aud anti-replay, weak posture surfaced: a no-expor non-audience-bound token is flagged, strict callers refuse withrequireExpiry); (2)authorizeCharge— the Programmable Payment: a charge only becomes an executable EIP-681 intent if it's inside what the agent's OWNER signed off — token, recipient allow-list, per-charge max, AND the cumulative cap (drain-safe: ten small charges can't beat a low cap; a malformed or absent limit is REFUSED, never treated as "no limit"). Both fail-closed; BIII does not verify JWT signatures itself (delegated, no dep).bin/biii-mcp.js— the agentic bridge: an MCP any agent loads (29 tools, counted from the exportedTOOLSlist — not from a regex over the source, which silently droppedtill_b20_authenticbecause its name carries digits:till_authorize,till_b20_authentic,till_check_invoice,till_check_payment,till_create_charge,till_create_invoice,till_export,till_floor,till_funder_history,till_key_exposure,till_kya,till_launch_funder,till_meter,till_open_approvals,till_receipt,till_recovery_offer,till_resolve,till_roll,till_rug_powers,till_seed_exposure,till_trace_theft,till_trust,till_verify_delivery,till_vet_agent,till_vet_approach,till_vet_asset,till_vet_meme,till_vet_merchant,till_watch_wallet) — an agent can vet a merchant or a tokenized asset, get the whole trust triangle in one call, issue or pay an invoice, keep a receipt, export the books, meter usage, prove its floor, resolve a buzz npub or a gitlawb did:key to a Base address, read a KYA identity, spend only within a signed authorization, and render provable books (till_roll)pitch/trust-triangle.html— the sellable white-label one-pager (self-contained, theme-aware)COMPETITION.md— the researched landscape (dated): ride the rails (x402/Stripe), interop with the standards (ERC-8004/Skyfire KYA), never custodial — the open layer is the non-custodial trust registryINTEGRATION-buzz.md/INTEGRATION-gitlawb.md— honest partnership briefs, each with a runnable offline proof (examples/buzz-agent-pays.js,examples/gitlawb-agent-pays.js— smoke-tested in CI so the demos can't rot): a keypair agent resolves→Base, a sanctioned counterparty is BLOCKED, a clean payment settles with a txHash-anchored receiptweb/— the merchant phone app (PWA): amount → QR → PAID ✓ → receipt
Business model — the trust+bridge layer partners resell
BIII is not (only) an app to grow one merchant at a time. It's a white-label trust + bridge layer that companies who already have the merchants plug in:
They bring the clientele. BIII brings the trusted USDC payment + the human/agent bridge + the provable receipts. Sold to PSPs, neobanks, merchant platforms, Base ecosystem apps.
The one-pager for that conversation — the trust triangle, the four verdict states, the
white-label split, the receipt, and the honest landscape — is pitch/trust-triangle.html
(self-contained, theme-aware, no external requests).
Lyzi is white-label for PSPs but terminal/enterprise and human-only. BIII is white-label too — and it's the one that also lets AI agents pay, ships un-fakeable consumer receipts, and runs non-custodially (the partner never touches the merchant's funds, so no money-transmitter custody to license). That combination is the wedge.
Stance: genuinely open to partners with distribution. We build compatible with Base/Coinbase/Flexa/Lyzi and claim no partnership until one is signed (anti-hype).
Trust roadmap — make BOTH sides safe
- Now: the payer is protected by field-for-field on-chain verification; the merchant can be
vetted via MainStreet's "safe to pay" reputation (
till_vet_merchant), advisory. - Next (ZK): privacy-preserving attestations so each side proves what matters without doxxing — "this merchant is verified", "this payer is reputable / has funds" — as a zero-knowledge badge, not a data dump. The receipt already proves the payment; ZK proves the parties. (Design tracked; not built yet — no ZK claims until it ships.)
The receipt & the books (the human layer)
lib/ledger.js turns a payment into a paper-ticket a non-crypto human instantly reads
(merchant, B3-####, item, amount, tip, ✓ PAID, a verify link) and a provable day roll for
the merchant — every line re-checkable on-chain, one txHash counted once, books that can't be
padded. Nobody offers this for in-person USDC today; it's the trust made legible.
Non-negotiables
Non-custodial by construction · descriptor-only (never signs, never custodies) · the chain is the only source of truth for "paid" · every receipt re-verifiable by anyone · real numbers only, no invented usage or partnerships.
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