Firefly III MCP Server

An MCP (Model Context Protocol) server that gives Claude full access to your Firefly III personal finance instance. Talk to Claude in natural language to record expenses, check balances, manage budgets, and more.

Features

• Transactions: Create, list, search, update, and delete transactions (withdrawals, deposits, transfers)

• Accounts: Manage asset, expense, revenue, liability, and cash accounts

• Categories: Organize transactions with categories

• Budgets: Create and manage budgets with auto-budget support

• Tags: Label transactions with flexible tags

Prerequisites

• Node.js >= 18

• A running Firefly III instance

• A Personal Access Token (PAT) from your Firefly III instance

Getting Your PAT

1. Log into your Firefly III instance

2. Go to Options → Profile → OAuth

3. Under Personal Access Tokens, create a new token

4. Copy the token — you'll need it for configuration

Installation

Via npm (recommended)

npm install -g firefly-iii-mcp-server

From source

git clone https://github.com/przbadu/firefly-iii-mcp-server.git
cd firefly-iii-mcp-server
npm install
npm run build

Configuration

Claude Desktop

Edit your Claude Desktop config file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

• Windows: %APPDATA%\Claude\claude_desktop_config.json

Using the npm-installed binary:

{
  "mcpServers": {
    "firefly-iii": {
      "command": "firefly-iii-mcp-server",
      "env": {
        "FIREFLY_III_URL": "https://your-firefly-instance.example.com",
        "FIREFLY_III_PAT": "your-personal-access-token-here"
      }
    }
  }
}

Or using npx (no global install needed):

{
  "mcpServers": {
    "firefly-iii": {
      "command": "npx",
      "args": ["-y", "firefly-iii-mcp-server"],
      "env": {
        "FIREFLY_III_URL": "https://your-firefly-instance.example.com",
        "FIREFLY_III_PAT": "your-personal-access-token-here"
      }
    }
  }
}

Claude Code CLI

claude mcp add firefly-iii \
  -e FIREFLY_III_URL=https://your-firefly-instance.example.com \
  -e FIREFLY_III_PAT=your-personal-access-token-here \
  -- npx -y firefly-iii-mcp-server

Or add it to your .claude/settings.json:

{
  "mcpServers": {
    "firefly-iii": {
      "command": "npx",
      "args": ["-y", "firefly-iii-mcp-server"],
      "env": {
        "FIREFLY_III_URL": "https://your-firefly-instance.example.com",
        "FIREFLY_III_PAT": "your-personal-access-token-here"
      }
    }
  }
}

Usage Examples

Once configured, just talk to Claude naturally:

Recording Transactions

"I spent $45.50 at Trader Joe's on groceries today"

"Record a $2,500 salary deposit from my employer into my checking account"

"Transfer $500 from Checking to Savings"

Querying

"Show me all my transactions from last week"

"How much did I spend on restaurants this month?"

"What's the balance of my checking account?"

Managing Finances

"Create a monthly grocery budget of $600"

"List all my expense categories"

"Tag my last 3 restaurant transactions as 'business meals'"

Available Tools

Development

# Watch mode with auto-reload
npm run dev

# Build for production
npm run build

# Run the built server
npm start

License

MIT