Setting Up MCP Servers
Through the Model Context Protocol (MCP), Apis AI connects external tools and data sources – from local file system servers to hosted APIs. They are managed in the Settings, then Extensions tab.
What Is MCP?
MCP is an open standard through which an LLM can discover and call a server's tools. Apis AI uses the official Kotlin SDK and supports both local processes and remote HTTP servers. The AI calls MCP tools within its normal tool loop – until the round limit is reached.
Local (stdio) vs. Remote (HTTP)
| Type | Behavior |
|---|---|
| Local (stdio) | Apis AI starts a local process and communicates via stdin/stdout. Suitable for servers running on your machine. |
| Remote (HTTP) | Connects to an HTTP URL. Suitable for hosted MCP servers; optionally with headers and OAuth. |
Adding a Server
- Create a server – in the Extensions tab under MCP servers, click Add MCP server.
- Choose a type – Local (stdio) or Remote (HTTP).
- Fill in the fields – depending on the type (see below).
- Save & connect – the app connects the server and shows the number of tools found.
Fields – Local (stdio)
| Field | Meaning |
|---|---|
| Command | The program to execute (e.g. npx, python, uvx). |
| Arguments | Space-separated arguments (e.g. -y @modelcontextprotocol/server-filesystem /pfad). |
| Environment variables | Key=Value, one per line – e.g. for API keys. |
npx or a
full path such as /usr/local/bin/uvx. A name is searched in the app's
PATH and in the tool directories that a program started from the desktop does
not have in its PATH: ~/.local/bin (uv/uvx, pipx),
~/.bun/bin, ~/.volta/bin, ~/.asdf/shims, the fnm
default alias and the bin directory of the newest nvm Node version under
~/.config/nvm or ~/.nvm, plus /usr/local/bin and
/snap/bin. The server process receives this widened search path as well, so
npx finds its node. If a server still reports a command that was
not found, see When Something Doesn't Work.
Fields – Remote (HTTP)
| Field | Meaning |
|---|---|
| URL | Address of the MCP endpoint. |
| Headers | Key=Value, one per line – e.g. a bearer token. |
| OAuth Client ID / Secret | Optional. Leave empty for automatic client registration. |
MCP Library
The MCP library helps with quick setup:
- Curated – hand-picked, common servers to adopt directly.
- Registry (online) – search the official MCP registry with "Load more" pagination.
With + you adopt an entry as a server card and then adjust paths, credentials or environment variables.
OAuth Sign-In
If a remote server requires a sign-in, the server card shows the status Sign-in required and a Sign in button. After successful authorization the token is stored locally and the server connects automatically.
Connection Status
| Status | Meaning |
|---|---|
| Connected (N tools) | Server is active; N tools are available to the AI. |
| Connecting… | Connection is being established. |
| Sign-in required | OAuth authorization pending. |
| Connection failed | Server could not be reached or started – check the configuration. The card shows the reason below the status, e.g. a missing program or a wrong path. |
| Disabled | Server is switched off individually. |
The sidebar always shows how many MCP servers are active. In workflow nodes, MCP servers can additionally be enabled or disabled individually (see Workflows).