firefly-iii-mcp

A Model Context Protocol (MCP) server that exposes curated tools for the Firefly III personal finance API. It is designed to be consumed by MCP-aware assistants so they can query account data, run autocompletion endpoints, and inspect transactions on behalf of the user.

Why use this MCP server?

• Thin wrapper over the official Firefly III REST API with built-in parameter validation via Zod.
• Ships as an executable MCP server so you never need to generate your own build artefacts.
• Works with any assistant or automation platform that speaks the Model Context Protocol over stdio.

Prerequisites

• A running instance of Firefly III with API access enabled.
• A personal access token that can read the resources you want to expose.
• Node.js 18 or later to install and run the MCP server locally.

Installation

Install the package globally (or add it to the environment that hosts your MCP clients):

npm install -g firefly-iii-mcp

You can also run it ad hoc with npx when configuring a new assistant:

npx firefly-iii-mcp --stdio

Configuration

Set the required Firefly III credentials before launching the server. A sample configuration lives in .env.example.

• FIREFLY_III_BASE_URL: For example https://demo.firefly-iii.org.
• FIREFLY_III_PAT: Personal access token generated from your Firefly III profile.

Export these variables in the same shell session that starts the MCP server, or store them in the configuration mechanism used by your assistant platform.

Running the MCP server

The CLI entry point speaks MCP over stdio, which allows plug-and-play integration with most clients:

firefly-iii --stdio

Refer to your assistant's documentation for details on registering an external MCP server. Typically, you will point it to the executable above and ensure the environment variables are in scope. Once connected, each Firefly III endpoint is published as an MCP tool that returns formatted JSON responses.

Tool catalogue

A curated summary of the most common tools lives in docs/TOOLS.md, together with examples for programmatically exploring the full catalogue.

Development notes

While consumers do not need to build anything manually, contributors can run:

npm install
npm run build

npm run build compiles TypeScript into the build/ directory and preserves the executable shebang for the CLI. The prepublishOnly script keeps published artefacts up to date.

Release notes

Version history and notable changes are documented in CHANGELOG.md.

Contributing

Contribution guidelines, commit conventions and release workflow details are documented in CONTRIBUTING.md.

Support

Questions, feature ideas, or bug reports are welcome on the issue tracker or via email at [email protected].