---
updatedAt: 2026-09-07T09:52:30.000Z
agentTools:
  projectIndex: https://developers.youtrust.com/llms.txt
---

# Set up and troubleshooting

Learn how to connect the Developer MCP to your AI tool, authenticate, and fix the most common errors.

# Setup

Youtrust hosts a remote MCP server at `https://developers.youtrust.com/mcp`. Simply add it to your AI tool's configuration, including your API key as a Bearer token in the `headers` field.

<Tabs>
  <Tab title="Cursor">
    **Add to&#x20;**`~/.cursor/mcp.json`**:**

    ```json
    {
      "mcpServers": {
        "youtrustAPIDoc": {
          "url": "https://developers.youtrust.com/mcp",
          "headers": {
            "Authorization": "Bearer '${YOUTRUST_API_KEY_SANDBOX}'"
          }
        }
      }
    }
    ```
  </Tab>

  <Tab title="Claude Desktop">
    **Add to&#x20;**`.claude.json`**:**

    ```json
    {
      "mcpServers": {
        "youtrustAPIDoc": {
          "url": "https://developers.youtrust.com/mcp",
          "headers": {
            "Authorization": "Bearer '${YOUTRUST_API_KEY_SANDBOX}'"
          }
        }
      }
    }
    ```
  </Tab>

  <Tab title="Claude Code">
    **Run this command:**

    ```bash
    claude mcp add --transport http youtrustAPIDoc https://developers.youtrust.com/mcp --header 'Authorization: Bearer ${YOUTRUST_API_KEY_SANDBOX}'
    ```
  </Tab>

  <Tab title="Codex">
    **Add to&#x20;**`~/.codex/config.toml`**:**

    ```toml
    [mcp_servers.youtrustAPIDoc]
    url = "https://developers.youtrust.com/mcp"
    http_headers = { "Authorization" = "Bearer '${YOUTRUST_API_KEY_SANDBOX}'" }
    ```

    Codex supports remote servers through the configuration file. The `codex mcp add` command is for local stdio servers.
  </Tab>

  <Tab title="VS Code">
    **Add to&#x20;**`.vscode/mcp.json`**:**

    ```json
    {
      "servers": {
        "youtrustAPIDoc": {
          "type": "http",
          "url": "https://developers.youtrust.com/mcp",
          "headers": {
            "Authorization": "Bearer '${YOUTRUST_API_KEY_SANDBOX}'"
          }
        }
      }
    }
    ```
  </Tab>
</Tabs>

Then, add the Youtrust API Key to your environment variable. For example for Linux & MacOS, in `~/.zshrc` or `~/.bashrc` files:

```bash
export YOUTRUST_API_KEY_SANDBOX="your_sandbox_api_key"
```

<Callout icon="📘" theme="info">
  ### Authentication is optional and only required for real API calls

  Parameters `headers` & `Authorization`  are optional and only useful if you plan to call Youtrust API within the Developer MCP.<br />If you don't need it, simply remove the corresponding lines, and don't export environment variable
</Callout>

The assistant now has access to your Youtrust documentation and, with a valid API key, to your account through the MCP server.

# Testing your setup

Once configured, test the connection:

1. **Open your AI tool**
2. **Start a new chat** with the assistant.
3. **Ask about the Youtrust API**, for example:
   * "Use the YoutrustAPIDoc mcp and list available endpoints."
   * "Use the YoutrustAPIDoc mcp and show me how to create a Signature Request in sandbox."
   * Or more complex one: "Use the YoutrustAPIDoc mcp and build the MVP flow from Signature Request creation to its activation, containing two Signers and a single file (dummy or to be provided by me), in backend's repository language."

# Troubleshooting

### `Missing Security Schemes`

Your API key is not reaching the server. Check these three points, in order:

1. **The server URL.** It must be `https://developers.youtrust.com/mcp`. Another address redirects, and HTTP clients drop the `Authorization` header on a cross-domain redirect, so the key never arrives.
2. **The&#x20;**`Bearer`**&#x20;prefix.** The header value must be `Bearer YOUR_API_KEY`, not the key on its own.
3. **Restart your AI tool.** MCP configuration is read when the client connects, so editing it while the tool is running has no effect.

### `Unsupported data format`

Send an explicit `Content-Type: application/json` header on write calls (`POST`, `PATCH`, `PUT`). The MCP does not always infer it from the request body.

### `This value should not be null` on a `file` field

Expected behaviour: the MCP cannot upload binary files. See [What the Developer MCP cannot do](#what-the-developer-mcp-cannot-do).

### `The agent misses part of the documentation`

Ask it to run several short, targeted searches instead of one long question. The documentation search matches keywords fairly literally, so a single multi-topic query can silently return an incomplete set.

***