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TypeScript SDK

@recourse/sdk wraps every read: integrity, gate verdicts, events, retirements, orders, claims and the propagation log. It also verifies evidence bundles and registry proofs offline, the same code this site runs in your browser on the verify page.

import { createPublicClient, http } from "viem";
import { baseSepolia } from "viem/chains";
import { loadDeployment, checkCredit, getIntegrity, getEventsOf,
         explainIntegrity, subjectKey } from "@recourse/sdk";
import deploymentJson from "./base-sepolia.json";

const dep = loadDeployment(deploymentJson);
const client = createPublicClient({ chain: baseSepolia, transport: http() });

// May this credit be used for CORSIA right now? Fails closed.
const v = await checkCredit(client, dep, {
  registry: "VERRA", projectId: 981, profile: "CORSIA_PHASE1", vintage: 2017,
});
if (!v.ok) console.log(v.reasonName);           // "UnderWatch"

// Why: integrity state plus every open event, in plain language.
const integrity = await getIntegrity(client, dep, "VERRA", 981);
const events = await getEventsOf(client, dep, subjectKey(1, 981));
console.log(explainIntegrity({ registry: 1, projectId: 981, integrity, events }));

In a contract

A token, marketplace or retirement contract can refuse a recalled credit in one line. The revert names the reason.

interface ICreditGate {
  // reverts with IntegrityUnknown, StateStale, RecallActive, UnderWatch,
  // VintageOutOfWindow, ProgrammeNotEligible or NoAuthorizationOnRecord
  function requireUsable(bytes32 subject, uint16 registry, uint8 profile, uint16 vintage) external view;
}

// subject = keccak256(abi.encode(uint16(1) /* VERRA */, uint64(projectId)))
gate.requireUsable(subject, 1, 0 /* GENERIC */, vintage);

MCP server for agents

A procurement or trading agent can check credits before it acts. The endpoint below speaks MCP over streamable HTTP (stateless) with five read-only tools: check_credit, explain_recall, list_recalls, verify_evidence, verify_claim.

Endpoint

https://recourse-recall.vercel.app/api/mcp

Pinned oracle keys

3 (ML-DSA-87, from data/keys/pq-pins.json)

curl -s https://recourse-recall.vercel.app/api/mcp \
  -H 'content-type: application/json' \
  -H 'accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"check_credit",
       "arguments":{"registry":"VERRA","projectId":902,"profile":"GENERIC"}}}'

JSON API

The check behind this site, as JSON: live registry status, on-chain integrity, open events and a verdict per policy profile.

GET /api/check?q=981
GET /api/check?q=9738-128704133-128704532-VCS-VCU-259-VER-BR-14-981-01012017-31122017-0

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