SDK & agent plugins

@sigil/client — the typed client, plus drop-in guards for LangGraph/LangChain and ElizaOS.

@sigil/client

A zero-dependency typed client for the Sigil ASP. It speaks MCP streamable-HTTP, surfaces x402 challenges as typed errors, and ships a one-line guard() for agents.

import { SigilClient } from "@sigil/client";

const sigil = new SigilClient(); // defaults to the live ASP on X Layer

const v = await sigil.screenTransaction({
  chainId: 196,
  from: "0x1111…",
  to: "0x7777…",
  data: "0xa22cb465…",
});

// v.verdict: 0 PASS · 1 WARN · 2 BLOCK — deterministic and sealed;
// the Merkle batch reference appears after anchoring
if (v.verdict === 2) throw new Error(`refusing to sign: ${v.reasons.join(", ")}`);

The decision one-liner most agents want:

const g = await sigil.guard(tx);            // PASS ⇒ allow
if (!g.allow) refuse(g.reason);             // WARN/BLOCK ⇒ refuse
// policy: await sigil.guard(tx, { allowWarn: true })

Payments (x402)

Unpaid priced calls throw SigilPaymentRequiredError carrying the full challenge (exact + EIP‑3009 primary, Permit2 fallback, on X Layer USD₮0). Settle and retry in one hook:

const sigil = new SigilClient({
  onPaymentRequired: async (challenge) => {
    const proof = await payWithYourWallet(challenge); // e.g. OKX Payment SDK
    return proof;                                      // PAYMENT-SIGNATURE value (v2)
  },
});

sigil_verify_verdict is free forever — await sigil.verifyVerdict(receiptId) works with no payment at all.

LangGraph / LangChain

Two integration styles from @sigil/client/langgraph:

As a tool the agent is prompted to call before signing:

import { tool } from "@langchain/core/tools";
import { sigilPreSignCheck } from "@sigil/client/langgraph";

const check = sigilPreSignCheck();
const sigilTool = tool(check.invoke, {
  name: check.name,
  description: check.description,
  schema: check.schema,
});
// add sigilTool to your ToolNode / createReactAgent tools

As a hard guard around the signer — the firewall path, no prompt needed:

import { guardSigner, SigilBlockedError } from "@sigil/client/langgraph";

const safeSign = guardSigner(wallet.sendTransaction);
await safeSign(tx); // throws SigilBlockedError instead of signing a drainer

ElizaOS

import { sigilPlugin } from "@sigil/client/eliza";

export const character = {
  name: "Trader",
  plugins: [sigilPlugin()],
  // the agent gains SIGIL_SCREEN_TRANSACTION and is instructed
  // to never sign when it returns BLOCK
};

See it working

The wallet pre-sign demo — a mock wallet whose sign button is controlled by real, live verdicts.
Every verdict links to a public receipt (/v/{id}) and an on-chain proof (/registry).

With OKX_API_KEY / OKX_API_SECRET / OKX_API_PASSPHRASE configured, the intel layer enriches every token scan with OKX DEX's curated token list (okx-dex-listed / okx-dex-unlisted in coverage/sources). Unconfigured, the gap is recorded honestly as gap:okx-dex-unconfigured — never guessed.

@sigil/client

Payments (x402)

LangGraph / LangChain

ElizaOS

See it working

OKX rails

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