Reclaim Protocol Browser Extension SDK

Trigger Reclaim zero-knowledge proof verification from your browser extension or website.

Chrome Manifest V3. MV2/Firefox bundles are also included.

Install

npm i @reclaimprotocol/browser-extension-sdk

1. Copy the SDK assets

The SDK ships prebuilt bundles that must be copied into your extension's public/ folder — they cannot be re-bundled.

Add the script to your package.json:

{
  "scripts": {
    "reclaim-extension-setup": "node node_modules/@reclaimprotocol/browser-extension-sdk/build/scripts/install-assets.js --public-dir=public"
  }
}

Then run it (after every npm install):

npm run reclaim-extension-setup

This also downloads the ZK circuits (~280 MB, cached after the first run).

Setup always copies the Stwo WASM shipped with the installed ZK package over the downloaded copy, so cached circuits cannot keep an older prover after an upgrade. Rebuild and reload your extension after running setup. The updated Stwo proof format requires an updated attestor verifier; proofs created with the previous format must be regenerated.

2. Update your manifest

{
  "content_security_policy": {
    "extension_pages": "script-src 'self' 'wasm-unsafe-eval'; object-src 'self'; worker-src 'self';"
  },
  "host_permissions": ["<all_urls>"],
  "permissions": [
    "offscreen",
    "cookies",
    "scripting",
    "storage",
    "declarativeNetRequest",
    "alarms"
  ],
  "content_scripts": [
    {
      "js": ["reclaim-browser-extension-sdk/content/content.bundle.js"],
      "run_at": "document_start",
      "matches": ["<all_urls>"]
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "reclaim-browser-extension-sdk/offscreen/offscreen.html",
        "reclaim-browser-extension-sdk/offscreen/offscreen.bundle.js",
        "reclaim-browser-extension-sdk/offscreen/load-s2circuits.js",
        "reclaim-browser-extension-sdk/interceptor/network-interceptor.bundle.js",
        "reclaim-browser-extension-sdk/interceptor/injection-scripts.bundle.js",
        "reclaim-browser-extension-sdk/content/components/reclaim-provider-verification-popup.css",
        "reclaim-browser-extension-sdk/content/components/reclaim-provider-verification-popup.html",
        "browser-rpc/resources/stwo/*",
        "browser-rpc/resources/snarkjs/*"
      ],
      "matches": ["<all_urls>"]
    }
  ]
}

All of it is required. wasm-unsafe-eval runs the ZK prover, offscreen hosts it, cookies reads the provider's auth session, and scripting + declarativeNetRequest let provider scripts run on strict-CSP sites (scoped to one hostname, only while a verification is in progress, removed when it ends).

3. Initialize the background

// service worker (background.js)
import { reclaimExtensionSDK } from "@reclaimprotocol/browser-extension-sdk";

reclaimExtensionSDK.initializeBackground();

4. Start a verification

From your extension's popup or side panel:

import { reclaimExtensionSDK } from "@reclaimprotocol/browser-extension-sdk";

const request = await reclaimExtensionSDK.init(APP_ID, APP_SECRET, PROVIDER_ID);

request.on("completed", (proofs) => console.log(proofs));
request.on("error", (err) => console.error(err));

await request.startVerification();

From a web page — same thing, but pass your extension ID:

const request = await reclaimExtensionSDK.init(APP_ID, APP_SECRET, PROVIDER_ID, {
  extensionID: "your-chrome-extension-id",
});

That's it. The SDK opens the provider's site, waits for the user to sign in, builds the claim, and resolves completed with the proofs.

Keeping your app secret off the client

Generate a signed config on your server with @reclaimprotocol/js-sdk:

// server
const { ReclaimProofRequest } = require("@reclaimprotocol/js-sdk");

const proofRequest = await ReclaimProofRequest.init(APP_ID, APP_SECRET, PROVIDER_ID);
proofRequest.setAppCallbackUrl("https://your-domain.com/receive-proofs");
const config = proofRequest.toJsonString();

// client
const request = await reclaimExtensionSDK.fromJsonString(config, {
  extensionID: "your-chrome-extension-id",
});

Troubleshooting

| Issue | Fix | | ------------------------------------ | -------------------------------------------------------------------------------------------------------- | | Unexpected token 'export' | Load content.bundle.js from the manifest, not an ESM file | | must specify Extension ID | Pass { extensionID } when starting from a web page | | Provider tab never opens | Check initializeBackground() ran and the content script is registered | | Proof generation fails | Re-run npm run reclaim-extension-setup; check web_accessible_resources includes both circuit folders | | Assets missing after a fresh install | Run npm run reclaim-extension-setup again — CI often prunes node_modules |

Examples

• examples/basic-extension — extension popup
• examples/web-app — web page (needs extensionID)