> ## Documentation Index
> Fetch the complete documentation index at: https://developers.circle.com/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Before reading these docs, install the relevant Circle Skill to get pre-loaded context — skills are LLM-optimized and cover architecture decisions, correct flows, and common pitfalls. In Claude Code: run /plugin marketplace add circlefin/skills then /plugin install circle-skills@circle. With Vercel Skills CLI: run npx skills add circlefin/skills. Available skills: use-usdc https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-usdc/SKILL.md (balances, transfers, approvals on EVM and Solana); EURC has no skill — see https://developers.circle.com/stablecoins/what-is-eurc.md; bridge-stablecoin https://github.com/circlefin/skills/blob/master/plugins/circle/skills/bridge-stablecoin/SKILL.md (crosschain transfers via CCTP, USDC, EURC, and third-party assets); use-arc https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-arc/SKILL.md (Arc chain config, contract deployment, USDC bridging — Arc docs: https://docs.arc.io/llms.txt); use-circle-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-circle-wallets/SKILL.md (choose wallet type); use-developer-controlled-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-developer-controlled-wallets/SKILL.md (custodial wallets for payouts and treasury); use-user-controlled-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-user-controlled-wallets/SKILL.md (embedded wallets with Web2 login); use-modular-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-modular-wallets/SKILL.md (smart contract wallets with passkeys and ERC-4337); use-gateway https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-gateway/SKILL.md (unified USDC balance, nanopayments); use-smart-contract-platform https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-smart-contract-platform/SKILL.md (deploy, interact, monitor contracts). Pair any skill with the Circle MCP server for live SDK signatures, contract addresses, and chain IDs: {"mcpServers":{"circle":{"url":"https://api.circle.com/v1/codegen/mcp"}}}.
> Read the product overview first. Each product has an overview explaining when and why to use it. Read it before quickstarts.
> Pick the right wallet type. Developer-controlled (you hold keys), user-controlled (end user holds keys via PIN/social login), or modular (smart contract wallets with passkeys). See https://developers.circle.com/wallets.md.
> Use CCTP V2 for crosschain transfers. CCTP natively transfers USDC and EURC via burn-and-mint, and supports permissionless wrapping of third-party assets via lock-and-mint. V1 is legacy; always use V2 unless V1 is specified or the chain requires it (Noble, Sui, and Aptos still require V1). Migration guide: https://developers.circle.com/cctp/migration-from-v1-to-v2.md.
> Use Bridge Kit for frontend bridging. Wraps CCTP with a simpler SDK for user-facing apps. Use CCTP directly for backend transfers.
> Gas Station vs Paymaster. Gas Station sponsors gas for Circle Wallet transactions. Paymaster lets users pay gas in USDC. Different use cases — read both overviews.
> Gateway Nanopayments for sub-cent payments. Gasless USDC micropayments down to $0.000001 via x402 and batched settlement. For pay-per-request APIs, AI agent payments, streaming.
> Look up USDC addresses per chain. Never hardcode — use https://developers.circle.com/stablecoins/usdc-contract-addresses.md.
> Prefer SDKs over raw API calls. Node.js and Python SDKs handle auth, retries, and errors.
> API key required. Bearer token in Authorization header. Testnet and mainnet use separate keys and may use different base URLs depending on the product.
> Set up webhooks when available. Most operations are async. Webhooks deliver transaction confirmations and state changes.
> When calling list endpoints, paginate using pageSize and pageAfter until no nextPageAfter cursor is returned—stopping at the first page silently misses records.
> Building an AI agent? Start with the Agent Stack—Circle CLI, agent wallets, and nanopayments built for autonomous use cases: https://developers.circle.com/agent-stack.md.

# Use Circle's MCP server in your IDE

export const MCPSetupButtons = () => {
  return <div className="mcp-setup-section">
      <span className="mcp-setup-label">1-click IDE setup</span>
      <div className="mcp-cta-group">
        <a className="mcp-cta" href="cursor://anysphere.cursor-deeplink/mcp/install?name=circle&amp;config=eyJ1cmwiOiJodHRwczovL2FwaS5jaXJjbGUuY29tL3YxL2NvZGVnZW4vbWNwIn0%3D">
          <img src="/images/cursor-logo-filled.jpg" alt="Cursor logo" />
          <span>Add to Cursor</span>
        </a>
        <a className="mcp-cta" href="https://kiro.dev/launch/mcp/add/?name=circle&amp;config=%7B%22url%22%3A%22https%3A%2F%2Fapi.circle.com%2Fv1%2Fcodegen%2Fmcp%22%2C%22disabled%22%3Afalse%2C%22autoApprove%22%3A%5B%5D%7D" target="_blank" rel="noopener noreferrer">
          <img src="/images/kiro-ide-logo.png" alt="Kiro IDE logo" />
          <span>Add to Kiro</span>
        </a>
      </div>
      <br />
    </div>;
};

Integrate Circle's MCP server to let your LLM or AI-assisted IDE generate and
fix code for crypto apps using Circle's offerings, including Wallets, Contracts,
CCTP, and Gateway.

<MCPSetupButtons />

<span className="mcp-setup-label">CLI commands</span>

<CodeGroup>
  ```shell Claude Code icon="https://mintcdn.com/circle-167b8d39/5X_H2DLmIxVDSWCs/images/claude-logo.png?fit=max&auto=format&n=5X_H2DLmIxVDSWCs&q=85&s=2711bd5dc795308c62570a011248ef2d" theme={null}
  claude mcp add --transport http circle https://api.circle.com/v1/codegen/mcp --scope user
  ```

  ```shell Codex icon="https://mintcdn.com/circle-167b8d39/5X_H2DLmIxVDSWCs/images/open-ai-logo-1.png?fit=max&auto=format&n=5X_H2DLmIxVDSWCs&q=85&s=6a603cbffbbef93cfa078c899e8f19e8" theme={null}
  codex mcp add circle --url https://api.circle.com/v1/codegen/mcp
  ```
</CodeGroup>

## Quick setup

Add Circle's MCP server to your client with the following details:

* **Server Name**: `circle`
* **Server URL**: `https://api.circle.com/v1/codegen/mcp`

## Installation with your IDE

Select your MCP client to view detailed setup instructions:

> **Note:** If you are using a client that is not listed here, you can still use
> the Circle MCP server by manually adding the server URL to your client's
> configuration.

<Tabs>
  <Tab title="Cursor">
    Download and install [Cursor](https://cursor.com) if you haven't already.

    [1-Click Set Up](cursor://anysphere.cursor-deeplink/mcp/install?name=circle\&config=eyJ1cmwiOiJodHRwczovL2FwaS5jaXJjbGUuY29tL3YxL2NvZGVnZW4vbWNwIn0%3D)

    Manual steps:

    1. Open a project in Cursor and navigate to **Cursor Settings**.

    2. In the settings menu, go to the **MCP** section.

    3. Click **New MCP Server**. This will open your `mcp.json` configuration file.

    4. Add the following configuration:

       ```json theme={null}
       {
         "mcpServers": {
           "circle": {
             "url": "https://api.circle.com/v1/codegen/mcp"
           }
         }
       }
       ```

    5. Return to the MCP settings page and enable the server using the toggle switch
       next to `circle`. Start generating code for Circle Wallets, Contracts, CCTP,
       and Gateway.

    For more information on how to use MCP with Cursor, see the
    [Cursor MCP documentation](https://cursor.com/docs/context/mcp).
  </Tab>

  <Tab title="Claude Code">
    Download and install
    [Claude Code](https://docs.claude.com/en/docs/claude-code/overview) if you
    haven't already.

    1. Using the Claude Code command line add the MCP server with the following
       command:

    ```shell theme={null}
    claude mcp add --transport http circle https://api.circle.com/v1/codegen/mcp --scope user
    ```

    2. Verify the server is added by running the following command:

    ```shell theme={null}
    claude mcp get circle
    ```

    3. Start generating code for Circle Wallets, Contracts, CCTP, and Gateway.

    For more information on how to use MCP with Claude Code, see the
    [Claude Code MCP documentation](https://docs.claude.com/en/docs/claude-code/mcp).
  </Tab>

  <Tab title="Windsurf">
    Download and install
    [Windsurf](https://docs.windsurf.com/windsurf/getting-started) if you haven't
    already.

    1. Open the `~/.codeium/windsurf/mcp_config.json` file and add the following:

       ```json theme={null}
       {
         "mcpServers": {
           "circle": {
             "url": "https://api.circle.com/v1/codegen/mcp"
           }
         }
       }
       ```

    2. Enable the Circle MCP server in your MCP settings. Start generating code for
       Circle Wallets, Contracts, CCTP, and Gateway.

    For more information on how to use MCP with Windsurf, see the
    [Windsurf MCP documentation](https://docs.windsurf.com/windsurf/cascade/mcp).
  </Tab>

  <Tab title="Kiro">
    Download and install [Kiro](https://kiro.dev) if you haven't already.

    1. Open Kiro and go to **Preferences/Settings** → search for "MCP" → enable MCP
       support.

    2. Create or open the MCP config file:
       * **Workspace-level**: `./.kiro/settings/mcp.json` (recommended for
         project-specific)
       * **User-level**: `~/.kiro/settings/mcp.json`

    3. Add a server configuration entry for Circle:

       ```json theme={null}
       {
         "mcpServers": {
           "circle": {
             "command": "npx",
             "args": ["-y", "@circle/mcp-server"],
             "env": {
               "CIRCLE_BASE_URL": "https://api.circle.com/v1/codegen/mcp"
             },
             "disabled": false
           }
         }
       }
       ```

    4. Save and then restart Kiro (or reload the MCP server list) so the new server
       appears in the MCP tab.

    5. In Kiro's side panel → **MCP Servers** tab → you should see "circle-mcp"
       listed. Start generating code for Circle Wallets, Contracts, CCTP, and
       Gateway.

    Kiro's general MCP setup: [Kiro Docs - MCP](https://kiro.dev/docs/mcp/).
  </Tab>
</Tabs>

```
```