Client setup

Every client uses the same URL:

https://www.ninjachat.ai/api/mcp

Web clients sign in with OAuth — no key. Editor and CLI clients need an nj_sk_ key from Developers → Keys. MCP calls are billable, so a key marked read-only is rejected — mint a full-access key.

Claude (claude.ai)

Settings → Connectors → Add custom connector. Name it NinjaChat, paste the URL, sign in when prompted. No API key.

ChatGPT

Settings → Connectors → Advanced → enable developer mode. Then Create a connector, name it NinjaChat, paste the URL, and approve the OAuth sign-in. Enable it in the composer.

Cursor

~/.cursor/mcp.json

{
  "mcpServers": {
    "ninjachat": {
      "url": "https://www.ninjachat.ai/api/mcp",
      "headers": {
        "Authorization": "Bearer nj_sk_YOUR_KEY"
      }
    }
  }
}

Cursor Settings → MCP should show ninjachat with a green dot. If not, reload the window.

Claude Code

claude mcp add --transport http ninjachat https://www.ninjachat.ai/api/mcp \
  --header "Authorization: Bearer nj_sk_YOUR_KEY"

Verify with /mcp. Add --scope user to use it in every project.

Listed as failed? Use --transport http (not sse) and keep the whole "Authorization: Bearer …" string as one shell argument.

Codex

~/.codex/config.toml

[mcp_servers.ninjachat]
url = "https://www.ninjachat.ai/api/mcp"
http_headers = { "Authorization" = "Bearer nj_sk_YOUR_KEY" }

Restart the session — config loads at launch.

TOML is picky: [mcp_servers.ninjachat] with an underscore, and http_headers as an inline table.

VS Code

.vscode/mcp.json

{
  "servers": {
    "ninjachat": {
      "type": "http",
      "url": "https://www.ninjachat.ai/api/mcp",
      "headers": {
        "Authorization": "Bearer nj_sk_YOUR_KEY"
      }
    }
  }
}

Click the Start code lens above the entry, then use it in Copilot Chat’s agent mode.

Hermes

~/.hermes/config.yaml

mcp_servers:
  ninjachat:
    url: "https://www.ninjachat.ai/api/mcp"
    headers:
      Authorization: "Bearer nj_sk_YOUR_KEY"
    enabled: true

Start a new session — the dashboard’s MCP panel shows the connection.

OpenClaw

openclaw mcp add ninjachat \
  --url https://www.ninjachat.ai/api/mcp \
  --transport streamable-http \
  --header "Authorization: Bearer nj_sk_YOUR_KEY"

Restart the gateway to load it.

Review or disconnect OAuth agents anytime in Developers → Agents.

Building your own OAuth client

NinjaChat is a full OAuth 2.1 authorization server, so any MCP client that speaks the standard flow connects without an API key:

Discovery. An unauthenticated request to the endpoint returns 401 with a WWW-Authenticate challenge pointing at https://www.ninjachat.ai/.well-known/oauth-protected-resource/api/mcp; the authorization-server metadata is at https://www.ninjachat.ai/.well-known/oauth-authorization-server.
Registration. Open Dynamic Client Registration at https://www.ninjachat.ai/api/oauth/register. Clients are public — there is no client secret — and the redirect_uri you authorize with must be one you registered. A client unused for 90 days is garbage-collected.
Authorization. https://www.ninjachat.ai/oauth/authorize with code_challenge_method=S256. PKCE is mandatory and plain is rejected; authorization codes expire after 60 seconds. The only scope is mcp.
Tokens. https://www.ninjachat.ai/api/oauth/token supports authorization_code and refresh_token. Access tokens (nj_at_…) last 1 hour; refresh tokens (nj_rt_…) last 30 days and rotate on every use — replaying a rotated refresh token revokes the whole token family. Revoke either token at https://www.ninjachat.ai/api/oauth/revoke.

Test it

Free, and proves auth end to end:

Use NinjaChat to check my balance.

Then make something:

Use NinjaChat to generate a poster of a neon koi fish,
comparing 3 models under $0.25.

Treat nj_sk_ keys like passwords — prefer user-level config over committed files, and revoke anything that leaks.

Get Started

Using It

Reference

Building your own OAuth client

Test it

​Building your own OAuth client

​Test it

Building your own OAuth client

Test it