Firefly III MCP Server: Give AI Agents Access to Your Budgets and Transactions

Why Give AI Access to Firefly III?

Firefly III is the self-hosted personal finance manager that tracks transactions, budgets, bills, and accounts. It gives you full control over your financial data with categories, tags, recurring transactions, and detailed reporting.

But when you're coding financial automation or building budgeting tools in Claude or Cursor, your AI assistant can't see your Firefly III instance. It can't look up recent transactions, check budget status, or verify account balances. You keep switching to the Firefly web interface.

With DataFaucet, you browse your Firefly III dashboard once and it captures the API calls as MCP tools. Now your AI coding assistant can query transactions, check budgets, and review spending patterns directly.

What AI Agents Can Do With Firefly III Access

Once DataFaucet creates an MCP server from your Firefly III session, AI agents can:

• Search transactions by description, amount, category, or date range
• Check budget status with spent vs. available amounts
• View account balances across all your accounts
• List categories and tags with transaction counts
• Review bills and subscriptions with due dates and auto-match rules
• Check recurring transactions and their schedules
• View piggy banks with saved amounts and targets

Setting Up Firefly III as an MCP Server with DataFaucet

Step 1: Browse Your Firefly III Dashboard

Open your Firefly III web interface and navigate through the Dashboard, Transactions, Budgets, Accounts, and Reports pages.

Step 2: DataFaucet Captures the API

DataFaucet's browser extension records the API calls your browser makes to Firefly III. Each call becomes a callable MCP tool with parameters and response types.

Step 3: Connect to Your AI Client

Add the generated MCP server to Claude Desktop, Cursor, or Windsurf. Your AI assistant can now query your financial data whenever it needs context.

Example: AI Checks Budget Status

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User: How's my grocery budget looking this month?

AI (via DataFaucet MCP): Groceries budget for June 2026:

• Budget: $600.00
• Spent: $412.38 (68.7%)
• Remaining: $187.62
• 18 days left in period
• On pace to spend $687 (over by $87)

\\\`

Example: AI Searches Transactions

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User: What did I spend at Amazon this month?

AI (via DataFaucet MCP): 4 Amazon transactions in June:

• Jun 1: $34.99 (Electronics category)
• Jun 5: $22.47 (Household category)
• Jun 12: $89.00 (Software category)
• Jun 18: $15.99 (Books category)
• Total: $162.45

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Why Not Just Use the Firefly III API Directly?

Firefly III has a comprehensive REST API with full OAuth support, but building a dedicated MCP server means writing endpoint wrappers for dozens of resources, handling token authentication, managing pagination, and keeping up with API changes.

DataFaucet skips all of that. It watches what your browser does and replicates those exact calls as structured MCP tools. If Firefly III updates its interface, you just re-capture.

Works With Any MCP Client

The Firefly III MCP server created by DataFaucet works with:

• Claude Desktop and Claude Code
• Cursor (AI-powered editor)
• Windsurf (Codeium's IDE)
• Any MCP-compatible client

Your AI gets real-time data from your Firefly III instance regardless of which tool you use.

Get Started

Create your Firefly III MCP server with DataFaucet — browse your finance dashboard once, get AI access to your budgets and transactions in under two minutes.