> For the complete documentation index, see [llms.txt](https://mcp-docs.nichefire.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mcp-docs.nichefire.com/quick-start/authentication.md).

# Authentication

Nichefire MCP doesn't support unauthenticated access, in order to access the MCP capabilities it is required to use one of the following authentication methods:

| Method                                                                           | Best for                                                                                            |
| -------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------- |
| [**OAuth 2.1**](/quick-start/authentication/authentication-through-oauth-2.1.md) | Interactive clients — Claude.ai, ChatGPT, Claude Code. No key to manage; sign in with your account. |
| [**API Key**](/quick-start/authentication/authentication-through-api-key.md)     | Scripts, curl, and manual integrations — a single `x-api-key` header.                               |

Both methods provide access to the same tools and use the same organization-level allowance reported by `get_usage`. The authentication method does not affect the capabilities available, result format, or usage calculation.

### Compatibility Matrix

The following matrix depicts the compatibility between the different supported integrations and the authentication methods supported:

<table><thead><tr><th>Client</th><th>OAuth</th><th width="95.41015625">API key</th><th>Setup</th></tr></thead><tbody><tr><td><strong>ChatGPT</strong></td><td>Yes</td><td>No</td><td><a href="/quick-start/supported-integrations/commercial-mcp-clients/chatgpt-apps.md">ChatGPT Apps</a></td></tr><tr><td><strong>Claude.ai (web)</strong></td><td>Yes</td><td>No</td><td><a href="/quick-start/supported-integrations/commercial-mcp-clients/claude-connectors.md">Claude Connectors</a></td></tr><tr><td><strong>Claude Desktop</strong></td><td>Yes</td><td>Yes</td><td><a href="/quick-start/supported-integrations/commercial-mcp-clients/claude-connectors.md">Claude Connectors</a></td></tr><tr><td><strong>Claude Code (CLI)</strong></td><td>Yes</td><td>Yes</td><td><a href="/quick-start/supported-integrations/commercial-mcp-clients/claude-connectors.md">Claude Connectors</a></td></tr><tr><td><strong>Cursor</strong></td><td>Yes</td><td>Yes</td><td><a href="/quick-start/supported-integrations/commercial-mcp-clients/cursor.md">Cursor</a></td></tr><tr><td><strong>VS Code</strong></td><td>Yes</td><td>Yes</td><td><a href="/quick-start/supported-integrations/commercial-mcp-clients/vs-code.md">VS Code</a></td></tr><tr><td><strong>Overall MCP Clients</strong></td><td>Yes</td><td>Yes</td><td></td></tr></tbody></table>

{% hint style="info" %}
Authentication determines whether the connection is authorized. The tools shown by the client are determined separately by your organization’s access to Firesearch, Trend Insights, or both.
{% endhint %}

Treat all credentials as confidential. Store API keys in the client’s designated credential field or an approved secrets manager. Do not include them in source control, shared documents, logs, or support tickets. If a credential is exposed or suspected to be compromised, contact Nichefire to have it revoked or rotated.

After choosing one Authentication method, continue to [Supported Integrations](/quick-start/supported-integrations.md).