diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
index 9d6d8bff..de90fd2e 100644
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@@ -1,6 +1,8 @@
 name: CI
 
-on: [push]
+on:
+  pull_request:
+    branches: main
 
 jobs:
   build:
@@ -8,14 +10,22 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
       - name: Use Node.js
         uses: actions/setup-node@v4
         with:
           node-version: "20.x"
+
       - uses: pnpm/action-setup@v3
         with:
           version: 8
           run_install: true
-      # - run: npm ci
-      # - run: npm run build --if-present
-      - run: npm test
+
+      - name: Get changes
+        run: git diff --name-only -r HEAD^1 HEAD
+
+      - name: Test
+        run: |
+          npx tsx ./src/verify.ts $(git diff --name-only -r HEAD^1 HEAD)
diff --git a/data/APU/data.json b/data/APU/data.json
index 90a6a657..5b28d44d 100644
--- a/data/APU/data.json
+++ b/data/APU/data.json
@@ -8,4 +8,4 @@
     "1": "0x594DaaD7D77592a2b97b725A7AD59D7E188b5bFa",
     "8453": "0x7A2C5e7788E55Ec0a7ba4aEeC5B3da322718Fb5e"
   }
-}
\ No newline at end of file
+}
diff --git a/src/utils.ts b/src/utils.ts
new file mode 100644
index 00000000..7dce95e5
--- /dev/null
+++ b/src/utils.ts
@@ -0,0 +1,36 @@
+import * as viemChains from "viem/chains";
+
+export interface SuperchainToken {
+  chainId: number;
+  address: string;
+  name: string;
+  symbol: string;
+  decimals: number;
+  logoURI: string;
+  extensions: {
+    standardBridgeAddresses: {
+      [chainId: string]: string;
+    };
+    opTokenId: string;
+  };
+}
+
+export interface TokenData {
+  name: string;
+  symbol: string;
+  decimals: number;
+  logoURI: string;
+  opTokenId: string;
+  addresses: {
+    [chainId: string]: string;
+  };
+}
+
+export const getViemChain = (id: number | string) => {
+  const chainId = typeof id === "string" ? parseInt(id) : id;
+  const chain = Object.values(viemChains).find((x) => x.id === chainId);
+  if (!chain) {
+    throw new Error(`Chain ${id} not found`);
+  }
+  return chain;
+};
diff --git a/src/verify.ts b/src/verify.ts
new file mode 100644
index 00000000..86f69190
--- /dev/null
+++ b/src/verify.ts
@@ -0,0 +1,119 @@
+import { readFileSync } from "fs";
+import { join } from "path";
+import { Address, createPublicClient, http } from "viem";
+import { isAddressEqual, isAddress } from "viem/utils";
+
+import { OptimismMintableERC20Abi } from "./abis/OptimismMintableERC20";
+import { StandardBridgeAbi } from "./abis/StandardBridge";
+import { getViemChain, TokenData } from "./utils";
+
+async function main() {
+  const [, , ...files] = process.argv;
+
+  for (const path of files) {
+    if (!path.startsWith("data") || !path.endsWith(".json")) {
+      continue;
+    }
+
+    let data: TokenData | null = null;
+    try {
+      data = JSON.parse(readFileSync(join(__dirname, "..", path)).toString());
+    } catch {
+      throw new Error(`Invalid JSON at ${path}`);
+    }
+
+    console.log("Verifying", data!.name);
+
+    let mintable = false;
+    let base = false;
+
+    for (const [chainId, address] of Object.entries(data!.addresses)) {
+      const client = createPublicClient({
+        chain: getViemChain(chainId),
+        transport: http(),
+      });
+
+      if (!isAddress(address)) {
+        throw new Error(`Invalid address for chainId ${chainId}`);
+      }
+
+      const [BRIDGE, REMOTE_TOKEN] = await Promise.all([
+        client
+          .readContract({
+            abi: OptimismMintableERC20Abi,
+            functionName: "BRIDGE",
+            address: address as Address,
+          })
+          .catch(() => null),
+        client
+          .readContract({
+            abi: OptimismMintableERC20Abi,
+            functionName: "REMOTE_TOKEN",
+            address: address as Address,
+          })
+          .catch(() => null),
+      ]);
+      console.log("BRIDGE", BRIDGE);
+      console.log("REMOTE_TOKEN", REMOTE_TOKEN);
+
+      // mintable
+      if (BRIDGE && REMOTE_TOKEN) {
+        mintable = true;
+        console.log(chainId, "is mintable");
+
+        const baseChainId = Object.entries(data!.addresses).find(
+          ([_, address]) => isAddressEqual(address as Address, REMOTE_TOKEN)
+        );
+        if (!baseChainId) {
+          throw new Error(
+            `No corresponding token address found for ${
+              data!.symbol
+            } on ${chainId}`
+          );
+        }
+
+        const baseClient = createPublicClient({
+          chain: getViemChain(baseChainId[0]),
+          transport: http(),
+        });
+
+        const BASE_BRIDGE = await client
+          .readContract({
+            abi: StandardBridgeAbi,
+            functionName: "OTHER_BRIDGE",
+            address: BRIDGE,
+          })
+          .catch(() => null);
+        if (!BASE_BRIDGE) {
+          throw new Error("BASE_BRIDGE not found");
+        }
+        console.log("BASE_BRIDGE", BASE_BRIDGE);
+
+        const REMOTE_BRIDGE = await baseClient
+          .readContract({
+            abi: StandardBridgeAbi,
+            functionName: "OTHER_BRIDGE",
+            address: BASE_BRIDGE,
+          })
+          .catch(() => null);
+        console.log("REMOTE_BRIDGE", REMOTE_BRIDGE);
+
+        if (!REMOTE_BRIDGE) {
+          throw new Error("REMOTE_BRIDGE not found");
+        }
+        if (!isAddressEqual(REMOTE_BRIDGE, BRIDGE)) {
+          throw new Error("Bridge addresses do not match");
+        }
+      } else {
+        base = true;
+      }
+    }
+
+    if (mintable !== true || base !== true) {
+      throw new Error("Tokens do not point at each other");
+    } else {
+      console.log("✅");
+    }
+  }
+}
+main();