MnemoPay

MnemoPay

The governance layer for AI agents that take consequential actions. Charter-driven mission scope, policy enforcement with human-in-the-loop approvals, FiscalGate budget enforcement, EU AI Act Article 12 audit bundles, Agent Reputation Scoring (300-850), and a tamper-evident MerkleAudit chain — whether the action moves money or changes infrastructure.

MnemoPay sits above the rail (Stripe, Paystack, Lightning, Stripe MPP, x402, Google AP2) and below the agent runtime (LangChain, CrewAI, Claude Agent SDK, your own loop). The rail moves money. The runtime decides. MnemoPay declares the rules, enforces the budget, and produces the evidence.

Payments are one kind of consequential action. The same charter, policy, approval and audit path governs operational tooling too — the primitives do not care whether the step settles a payment or drains a node.

npm install @mnemopay/sdk

New here? Start at docs/QUICKSTART.md — 60 seconds, three steps, working code.

Docs: Quickstart · Architecture · Permissions · Action ledger · Integrations (OpenAI/Anthropic/Gemini/Cohere/Mistral/LangGraph) · Recall · FiscalGate · Audit bundles (EU AI Act Art. 12) · Subpath import rule · Claude Agent SDK guide · Bundlers: Vite · Webpack · Bun

Community: LICENSE (Apache 2.0) · CHANGELOG · CONTRIBUTING · CODE_OF_CONDUCT · SECURITY · Discussions · Good first issues

Receipts: Trust hub (entity, KYB, Apple Team ID, Article 12 audit chain — verify in <5 min) · Benchmarks (1M ops, 100% adversarial detection, $0 ledger drift) · Python SDK on PyPI (Mock/Stripe/Paystack/Lightning rails, scoring and AuditChain; Charter, FiscalGate and Article 12 are TypeScript-only so far)

import MnemoPay, {

Charter, FiscalGate, MerkleAudit, // governance primitives AgentReputationScoring, BehavioralEngine, // trust + reputation StripeRail, X402Rail, GoogleAP2Rail, // rails } from "@mnemopay/sdk";

const agent = MnemoPay.quick("my-agent");

await agent.remember("User prefers monthly billing"); const tx = await agent.charge(25, "Monthly API access"); // FiscalGate hold await agent.settle(tx.id); // FiscalGate capture

// Agent Reputation Score — portable, 300-850 range. NOT FICO-brand, NOT a consumer // credit report, NOT governed by FCRA. Scores agents (software), not humans. const scorer = new AgentReputationScoring(); const result = scorer.compute({ transactions: [tx], createdAt: new Date(), /* ... */ }); // → { score: 672, rating: "good", feeRate: 0.015, trustLevel: "standard" }

Native Node ESM (`.mjs` or `"type": "module"`): the package is CommonJS, so a default import yields the whole module object. Use the named export instead: import { MnemoPay, Charter } from "@mnemopay/sdk", then MnemoPay.quick(...). The default-import form above works in TypeScript and bundlers.

14 modules. Hash-chained ledger. Charter / FiscalGate / Article 12 audit bundles. 6 payment rails. 200K-operation stress tested. Apache 2.0.

What MnemoPay is NOT: not a bank, not a money transmitter, not a Stripe replacement, not an agent framework, not a compliance platform. It's the rules-and-evidence layer between the rail and the runtime.

Governance latency (sub-second invariant)

"Sub-second governance" is a tested invariant, not marketing. The bench in tests/bench/governance-latency.bench.ts measures each governance hot path with vitest bench and emits a grep-able [gov-bench] summary line per scenario. Numbers below are steady-state percentiles from npm run bench:governance (run on the dev machine — your hardware will differ; the relative ordering is what matters).

Both per-event hot paths (evaluateAction, MerkleAudit.record) clear an entire EU AI Act policy gate and audit-chain write two orders of magnitude inside one millisecond. The end-to-end remember() path — including Ed25519 sign + sequence + chain emit — still sits comfortably inside the "sub-second governance" envelope with three decimal-orders of headroom.

A CI-enforced guard spec in tests/governance/latency-invariant.test.ts runs a degraded-mode sample on every npm test and fails if p95 for policy.evaluateAction regresses past 1 ms, or MerkleAudit.record past 5 ms. Bounds are sized to catch a ~10x regression, not flap on jitter.

How to reproduce: npm run bench:governance (full vitest.bench harness) or npm test -- latency-invariant (CI-bound check).

Native rails

Every rail ships with the same PaymentRail interface as StripeRail / PaystackRail / LightningRail:

Plus the Spatial governance fold — attachSpatialEvidence() co-signs the MerkleAudit chain with GridStamp proof-of-presence for embodied agents (drones, robots). Loose-coupled — no gridstamp runtime dependency.

Subpath imports for smaller, safer consumers

If you only need one MnemoPay module, import that subpath instead of the package root. This keeps MCP servers and other stdio tools quiet, avoids pulling unused middleware into bundles, and makes the dependency boundary obvious.

import { localEmbed, cosineSimilarity } from "@mnemopay/sdk/recall";

import { StripeRail, X402Rail } from "@mnemopay/sdk/rails"; import { SQLiteStorage } from "@mnemopay/sdk/storage"; import { CommerceEngine } from "@mnemopay/sdk/commerce";

Use the root import when you want the full SDK surface. Use @mnemopay/sdk/mcp only when you are intentionally mounting the MnemoPay MCP server.

Swarm (stable — v1.11+)

@mnemopay/sdk/swarm is the missing piece that browse.sh shipped as a public skill catalog. Ours adds the bit they don't: every agent in the swarm carries a DID, every action is FiscalGate-prechecked against per-agent + total caps, every TaskResult is appended to a shared Article-12 audit chain, and every skill invocation is billable through the same hash-chained ledger the rest of the SDK already uses.

CLI: npx @mnemopay/swarm list · npx @mnemopay/swarm demo — see mnemopay-swarm.

import { Swarm } from "@mnemopay/sdk/swarm";

import { AuditChain } from "@mnemopay/sdk/governance"; import { open } from "@mnemopay/browser"; // any BrowserProvider works

const provider = await someProviderFactory(); const swarm = new Swarm({ size: 4, provider, did: "did:mp:abc...", budget: { perAgent: 0.25, total: 1.00 }, audit: { chain: new AuditChain() }, });

const run = await swarm.spawn([ { id: "t1", skillId: "ramp.com/expense-create", prompt: "submit $42 lunch" }, { id: "t2", skillId: "linear/issue-create", prompt: "file UI bug" }, { id: "t3", skillId: "cloudflare/dns-record-set", prompt: "add CNAME" }, ]);

const results = await swarm.gather(run); const final = await swarm.recombine(results, "merge-json");

When to use it. Any time you'd open N parallel browser sessions to attack a problem — multi-source research, cross-platform issue triage, A/B-style "ask three agents, take the majority answer" — but you want one audit bundle, one budget envelope, and one place where billing happens.

Three recombine strategies (plus your own).

• first-success — returns the output of the first ok:true task; perfect for race patterns where any answer is fine.
• majority-vote — returns the most-common output across ok:true tasks; perfect for fact-extraction where consensus matters.
• merge-json — deep-merges every ok:true object output with sorted keys (deterministic across runs).
• concat — joins string outputs with \n in spawn order.
• Or pass any (results) => unknown callback.

Skill catalog. Public listings live at mcp.mnemopay.com/skills. The catalog is intentionally small and honestly marked — verified-partner badges only show after a real partnership is signed. Everything else carries verified: false, status: 'pending-partner' so you know exactly what trust tier you're getting.

BrowserSwarm — native browser-session fan-out (stable since 1.11.0)

@mnemopay/sdk/swarm/browser extends Swarm with a typed step sequence (goto / act / extract / screenshot / wait) per task and a lazy wire to @mnemopay/browser (optional peer dep — installing the SDK does NOT pull Playwright). Each task gets its own browser session, every step appends a browser.step event to the shared audit chain, and a thrown step kills only that one task — sibling sessions keep running.

import { BrowserSwarm } from "@mnemopay/sdk/swarm/browser";

const swarm = new BrowserSwarm({ size: 3, provider: undefined as never, budget: { perAgent: 0.25, total: 1.00 }, browser: { provider: "stagehand" }, }); const run = await swarm.spawn([ { id: "amzn", prompt: "amazon price", steps: [{type:"goto", url:"https://amazon.com/dp/X"}, {type:"extract", selector:"#priceblock_ourprice"}] }, { id: "bby", prompt: "best buy price", steps: [{type:"goto", url:"https://bestbuy.com/site/X"},{type:"extract", selector:".priceView-customer-price"}] }, { id: "tgt", prompt: "target price", steps: [{type:"goto", url:"https://target.com/p/X"}, {type:"extract", selector:"[data-test=product-price]"}] }, ]); const results = await swarm.gather(run); // BrowserTaskResult[] with .screenshots + .extractedData

File issues at github.com/mnemopay/mnemopay-sdk.

Audit-only middleware — .audit(client) with streaming + on-di