MCP integration

Two directions of MCP

Stack is both a producer and a consumer of MCP:

• Producer: Stack itself is an MCP server (ashlr-stack-mcp). The source declares 19 tools, a subset of CLI commands, including stack add and stack doctor.
• Consumer: When you stack add a service that has its own MCP server (Supabase, PostHog, Sentry, GitHub, Linear), Stack may merge that server's configuration into your project's .mcp.json. An entry alone does not establish usable credentials or a loaded client.

Installing Stack as an MCP server

The repository includes a Claude Code plugin. In Claude Code, add the marketplace and install its Stack plugin:

/plugin marketplace add ashlrai/ashlr-stack
/plugin install stack@ashlr

Or configure the stdio server in your MCP client. It also needs the stack CLI on PATH, or an absolute CLI path in STACK_BIN. The dual-package example below supplies both commands through npx.

Published CLI and MCP packages are currently 0.1.1 and require Bun 1.2 or newer on PATH, including when installed through npm or launched with npx. This reference describes source 0.2.1, which is not a published-version claim. The example pins those public versions; check the tools advertised by your installed server.

Example stdio configuration

{
  "mcpServers": {
    "ashlr-stack": {
      "command": "npx",
      "args": ["-y", "-p", "@ashlr/stack@0.1.1", "-p", "ashlr-stack-mcp@0.1.1", "ashlr-stack-mcp"]
    }
  }
}

Client configuration

Claude Code, Cursor, Windsurf and Zed have their own configuration locations and formats. Adapt the stdio command and arguments to your client's MCP settings; this JSON example does not define a universal global config file.

Project selection

Stack uses the server process's working directory. Confirm that your client launches it in the intended project; the snippet does not set that directory.

Tools — 19 total

The table describes the reviewed source contract; installed versions may differ. Check the tools your server actually advertises. Each declared tool dispatches CLI arguments from its input schema. The server spawns stack <args> with NO_COLOR=1 and CI=1. It returns stdout and any nonempty stderr as text, with isError reflecting command completion. The server is a control plane, not a sandbox or redaction layer; results are not universally JSON.

Resources

Up to three read-only resources are advertised when their files exist in the server's working directory. Reads return the file text. Confirm the intended project and inspect private configuration before exposing it; read-only does not mean redacted:

Provider-side MCP servers

Several provider adapters may emit MCP entries during stack add. The table describes source configuration merged into .mcp.json, not verified installed packages, reachable endpoints or client acceptance:

Plugin slash commands

The Claude Code plugin supplies instructions for these six commands to invoke MCP tools. Inspect returned results; these instructions do not guarantee interactive setup or provider success:

• /stack:add — request service setup through stack_add.
• /stack:doctor — inspect the configured-service health report.
• /stack:list, /stack:status — inspect configured services and status.
• /stack:recommend, /stack:apply — retrieve providers and apply a saved recipe.

Illustrative tool request

This is an illustrative source tool request, not a recorded successful interaction. stack_add can contact a provider and create resources; it is not a preview. Inspect returned CLI text, local writes and provider results separately. An emitted MCP entry does not prove that a client loaded it or that its credentials work:

{
  "name": "stack_add",
  "arguments": { "service": "supabase" }
}