TS/JS + Fetch

Learn how to mint a standard CIP-25 NFT using TypeScript or JavaScript with the Anvil API.

This example requires several utility and configuration files. Create the following files in the same directory as your main script.

Need to create wallets?

You can use the Anvil Wallet CLI to generate the required wallet JSON files for these examples.

https://github.com/Cardano-Forge/anvil-api-examples/blob/main/utils/constant.ts

// See Authentication page for API key details.
export const X_API_KEY = "testnet_EyrkvCWDZqjkfLSe1pxaF0hXxUcByHEhHuXIBjt9";
export const NETWORK = "preprod";
export const API_URL = `https://${NETWORK}.api.ada-anvil.app/v2/services`;
export const HEADERS = {
  "Content-Type": "application/json",
  "x-api-key": X_API_KEY,
};

You will also need the shared utility functions, which you can find in the utils/shared.ts file in the examples repository.

https://github.com/Cardano-Forge/anvil-api-examples/blob/main/documentation-references/metatemplate.json

{
	"name": "TBD",
	"image": [
		"https://ada-anvil.s3.ca-central-1.amazonaws.com/",
		"logo_pres_V2_3.png"
	],
	"mediaType": "image/png",
	"description": "Testing CIP-25 using anvil API"
}

Now, you can run the main script:

https://github.com/Cardano-Forge/anvil-api-examples/blob/main/documentation-references/cip25.ts

/**
 * CIP-25 NFT Minting Example
 *
 * This script demonstrates how to mint a standard CIP-25 Non-Fungible Token (NFT).
 * It handles everything from wallet loading to transaction submission.
 *
 * This involves:
 * 1. Loading a customer wallet (to pay for fees) and a policy wallet (to sign the policy).
 * 2. Creating a time-locked native script that expires in the future.
 * 3. Defining the asset metadata according to the CIP-25 standard.
 * 4. Building the transaction payload with the minting details.
 * 5. Building the transaction via the Anvil API.
 * 6. Signing the transaction with the customer and policy private keys.
 * 7. Submitting the fully signed transaction to the blockchain.
 *
 * Prerequisites:
 * - `wallet-customer.json`: A funded wallet file to pay for the transaction.
 * - `wallet-policy.json`: A wallet file to act as the policy key.
 * - `metatemplate.json`: A file containing the base structure for the CIP-25 metadata.
 * - `ANVIL_API_KEY`: An environment variable for Anvil API authentication.
 *
 * Execution:
 * `deno run --allow-all --env-file=.env cip25.ts`
 */

import { Buffer } from "node:buffer";
import { FixedTransaction, PrivateKey } from "npm:@emurgo/cardano-serialization-lib-nodejs@14.1.1";
import { createNativeScript, timeToSlot, getKeyhash } from "../utils/shared.ts";
import { API_URL, HEADERS } from "../utils/constant.ts";

// 1. Load wallets
const customerWallet = JSON.parse(Deno.readTextFileSync("wallet-customer.json"));
const policyWallet   = JSON.parse(Deno.readTextFileSync("wallet-policy.json"));

// 2. Create native script (expires 2026-01-01)
const slot = await timeToSlot(new Date("2026-01-01"));

// 2.1. Get keyhash of policy wallet
const keyhash = await getKeyhash(policyWallet.base_address_preprod);

// 2.2. Create native script
const nativeScript = await createNativeScript(keyhash!, slot);

// 3. Prepare mint payload (single NFT, counter based on timestamp for uniqueness)
const counter = Date.now();
const assets = [{
  version: "cip25",
  assetName: { name: `anvilapicip25_${counter}`, format: "utf8" },
  metadata: {
    ...(JSON.parse(Deno.readTextFileSync("metatemplate.json"))),
    name: `anvil-api-${counter}`,
  },
  policyId: nativeScript.hash,
  quantity: 1,
}];

// 4. Build transaction via Anvil API
const buildBody = {
  changeAddress: customerWallet.base_address_preprod,
  mint: assets,
  preloadedScripts: [nativeScript],
};

console.log("Build Body: ", buildBody);

const buildResult = await fetch(`${API_URL}/transactions/build`, 
  { method: "POST",
    headers: HEADERS,
    body: JSON.stringify(buildBody) 
  });
const buildJson = await buildResult.json();

console.log("Build Output: ", buildJson);

if (!buildResult.ok) throw new Error(buildJson.message ?? "Unable to build tx");

// 5. Sign (policy and customer using CSL)
const tx = FixedTransaction.from_bytes(Buffer.from(buildJson.complete, "hex"));
tx.sign_and_add_vkey_signature(PrivateKey.from_bech32(policyWallet.skey));
tx.sign_and_add_vkey_signature(PrivateKey.from_bech32(customerWallet.skey));

// 6. Submit via Anvil API
const submitResult = await fetch(`${API_URL}/transactions/submit`,
  { method: "POST",
    headers: HEADERS,
    body: JSON.stringify({ transaction: tx.to_hex(), signatures: [] })
  });
const submitJson = await submitResult.json();
if (!submitResult.ok) throw new Error(submitJson.message ?? "Unable to submit tx");

console.log("Submitted Transaction Hash: ", submitJson.txId ?? submitJson);

/*
Sample Output

Build Body:  {
  changeAddress: "addr_test1qqwadht4defe0cqem6a56ytwz96g4y7j7z0a02y5aj8c4unm5k2xfvhpn4kukwhsfakq22dy94yf9y8nt9dddzpkmuys4r5q8h",
  mint: [
    {
      version: "cip25",
      assetName: { name: "anvilapicip25_1752700276552", format: "utf8" },
      metadata: {
        name: "anvil-api-1752700276552",
        image: [
          "https://ada-anvil.s3.ca-central-1.amazonaws.com/",
          "logo_pres_V2_3.png"
        ],
        mediaType: "image/png",
        description: "Testing CIP-25 using anvil API",
        epoch: 1752700276552
      },
      policyId: "4d5bd6249f0d9e4b2762ce334e2973dc7fd414ec1e08b4b0c2159bfb",
      quantity: 1
    }
  ],
  preloadedScripts: [
    {
      type: "simple",
      script: { type: "all", scripts: [ [Object], [Object] ] },
      hash: "4d5bd6249f0d9e4b2762ce334e2973dc7fd414ec1e08b4b0c2159bfb"
    }
  ]
}
Build Output:  {
  hash: "72be679ccc4cadce0109beeda0dd182b8439204f252db7b4acbffd2f568f53a8",
  complete: "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",
  stripped: "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",
  witnessSet: "a101d90102818201828200581c3910f0db63599cd9cb1484d5591491629470761a89cde0473e4b94f682051a06a60080",
  auxiliaryData: "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"
}
Submitted Transaction Hash:  {
  txHash: "72be679ccc4cadce0109beeda0dd182b8439204f252db7b4acbffd2f568f53a8"
}
*/

Learn More

For a step-by-step explanation, see the Mint a CIP-25 NFT Guide.