freeagent mcp server

FreeAgent MCP Server

A Model Context Protocol server for FreeAgent accounting. Gives Claude (or any MCP client) the ability to reconcile bank transactions with receipts, claim expenses and mileage, raise and chase invoices, record supplier bills, log time against projects, and read the company's financial position.

What access this server requires

FreeAgent

The FreeAgent OAuth credentials grant full access to the connected FreeAgent account. This server uses that access to:

Action	Tools that use it
Read bank accounts	freeagent_list_bank_accounts
Read bank transactions and explanations	freeagent_list_transactions
Update transaction explanations (category, description, project, rebilling, VAT, approval, attachments)	freeagent_explain_transaction
Read, create, amend and delete expense claims	freeagent_list_expenses, freeagent_create_expense, freeagent_create_mileage_expense, freeagent_update_expense, freeagent_delete_expense
Read the chart of accounts	freeagent_list_categories
Read, create, amend and delete projects	freeagent_list_projects, freeagent_create_project, freeagent_update_project, freeagent_delete_project
Read, create, amend and delete contacts	freeagent_list_contacts, freeagent_create_contact, freeagent_update_contact, freeagent_delete_contact
Read, raise, edit and change the status of invoices	freeagent_list_invoices, freeagent_get_invoice, freeagent_create_invoice, freeagent_update_invoice, freeagent_update_invoice_status
Read, record and amend supplier bills	freeagent_list_bills, freeagent_get_bill, freeagent_create_bill, freeagent_update_bill
Read, log and amend time against project tasks	freeagent_list_tasks, freeagent_create_task, freeagent_update_task, freeagent_list_timeslips, freeagent_create_timeslip, freeagent_update_timeslip
Read accounting reports	freeagent_profit_and_loss, freeagent_trial_balance, freeagent_aged_debtors, freeagent_aged_creditors, freeagent_tax_timeline, freeagent_company_summary
Delete expenses, invoices, bills, contacts, projects, tasks and timeslips	freeagent_delete_expense, freeagent_delete_invoice, freeagent_delete_bill, freeagent_delete_contact, freeagent_delete_project, freeagent_delete_task, freeagent_delete_timeslip

FreeAgent does not offer granular OAuth scopes — authorising an app grants access to all of the above.

Destructive operations. The delete tools are flagged destructiveHint: true so your MCP client can prompt before running them, as is freeagent_update_invoice_status (its mark_as_cancelled transition voids an issued invoice). The three whose loss is unrecoverable — freeagent_delete_expense, freeagent_delete_contact and freeagent_delete_project — additionally require confirm: true, so a client that auto-approves tool calls still cannot trigger them by accident. The server never deletes bank transactions, and never emails anything to your clients — status transitions change status only.

Outbound fetches. freeagent_explain_transaction, freeagent_create_expense, freeagent_update_expense, freeagent_create_bill and freeagent_update_bill each accept a fileUrl to download a receipt or invoice. That URL is treated as untrusted input: only http/https are allowed, hosts resolving to loopback, link-local, or private addresses are refused (on the initial request and on every redirect), and downloads are capped at 10 MB.

Local file reads. Those same tools accept a filePath, and the server reads that file from the host it runs on. The path must be absolute, and symlinks are resolved before the check. Over stdio the server runs as you, so this is no more access than the client already has. In HTTP mode the caller is remote, so local paths are refused outright unless you set FREEAGENT_ATTACHMENT_ROOTS to the directories that may be read (colon-separated); anything outside them is refused. Set it in stdio mode too if you want to bound what a prompt-injected model can attach.

Truncation. List tools page through results and report mayHaveMore; when true, any total they return covers only the records fetched and is named totalOutstandingForReturned. The freeagent_aged_debtors and freeagent_aged_creditors reports page to exhaustion and return complete: true — treat complete: false as an incomplete figure. Records whose due date is missing or unparseable are counted in a separate unknown_due_date bucket rather than being assumed not yet due.

Email and file sources (external — not provided by this server)

This server has no email tools. For receipt/invoice search to work automatically, connect one or more of the following MCP servers alongside this one:

• Gmail (e.g. mcp__claude_ai_Gmail) — personal email
• Microsoft 365 / Outlook (e.g. mcp__claude_ai_microsoft-365) — business email

When both are connected, Claude will search all of them automatically for matching receipts before asking you to provide a file manually.

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Tools

Banking and expenses

Tool	Description
freeagent_list_bank_accounts	List all bank accounts and their IDs
freeagent_list_transactions	List transactions (unexplained / explained / all / marked_for_review) with date filters
freeagent_explain_transaction	Update, approve, rebill or attach a receipt to a transaction explanation
freeagent_list_categories	List the full chart of accounts — all four category groups
freeagent_list_expenses	List expense claims by date or project, with unbilledOnly for costs queued to bill on and untaggedRebillOnly for project-tagged costs that will never be billed
freeagent_create_expense	Create an expense claim with optional receipt (local path, URL or base64), project tag with rebill type/factor, EC VAT status and bank-transaction auto-matching
freeagent_update_expense	Update an existing expense — attach or replace the receipt, set the rebill treatment, retag project/category, correct date, amount or VAT
freeagent_create_mileage_expense	Create a mileage claim with engine type/size for fuel VAT, optionally rebilled to a project; the rate comes from the account's own mileage settings
freeagent_delete_expense	Delete an expense filed in error (needs confirm: true)

Contacts, invoicing and bills

Tool	Description
freeagent_list_contacts	List clients and suppliers, with an optional name/email filter
freeagent_create_contact	Create a client or supplier, with VAT registration number and default payment terms
freeagent_update_contact	Update a contact, add its VAT number, or hide it (status: "Hidden")
freeagent_delete_contact	Delete a contact (needs confirm: true)
freeagent_list_invoices	List invoices by view (overdue, open_or_overdue, draft, paid…) with the total outstanding
freeagent_get_invoice	Fetch one invoice in full, including line items
freeagent_create_invoice	Raise an invoice with line items and EC VAT status — always created as a draft
freeagent_update_invoice	Edit a draft invoice — dates, project, VAT status, discount, and add/edit/remove line items
freeagent_update_invoice_status	Mark an invoice as sent, draft, scheduled or cancelled (no email is sent)
freeagent_delete_invoice	Delete an invoice
freeagent_list_bills	List supplier bills with the total outstanding
freeagent_get_bill	Fetch one bill in full, including line items and their URLs (needed to edit lines)
freeagent_create_bill	Record a supplier bill, with optional invoice attachment (local path, URL or base64), EC VAT status, project allocation and rebill treatment
freeagent_update_bill	Update a bill — reference, dates, VAT status, project, rebill treatment, attachment and line items
freeagent_delete_bill	Delete a bill

Time tracking

Tool	Description
freeagent_list_tasks	List project tasks (time is always logged against a task)
freeagent_create_task	Create a project task with its billing rate
freeagent_update_task	Rename a task, change its billing rate, or close it (status: "Completed")
freeagent_delete_task	Delete a task with no time logged against it
freeagent_list_timeslips	List logged time for a date range, with totals per project; view: "unbilled" finds uninvoiced work
freeagent_create_timeslip	Log time against a project task
freeagent_update_timeslip	Correct a timeslip's hours, date, task or comment
freeagent_delete_timeslip	Delete a timeslip

Projects

Tool	Description
freeagent_list_projects	List projects, for tagging expenses, invoices, bills and time
freeagent_create_project	Create a project against a client contact — only contact and name are required
freeagent_update_project	Rename, rebudget, change billing rate or close a project
freeagent_delete_project	Delete a project with nothing booked against it (needs confirm: true)

Reporting

Tool	Description
freeagent_profit_and_loss	Income, expenses, operating profit, corporation tax estimate and retained profit
freeagent_trial_balance	Balance on every nominal account
freeagent_aged_debtors	Unpaid customer invoices bucketed by age (not yet due, 1–30, 31–60, 61–90, 90+ days)
freeagent_aged_creditors	Unpaid supplier bills bucketed by age
freeagent_tax_timeline	Upcoming VAT, corporation tax and Companies House deadlines with amounts due
freeagent_company_summary	Company details, VAT registration and accounting year end

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Prerequisites

FreeAgent OAuth credentials

1. Log in to FreeAgent → Settings → Developer API.
2. Create an OAuth application. Set the redirect URI to http://localhost:8080/callback.
3. Note your Client ID and Client Secret.
4. Run the bundled auth command to complete the OAuth flow and save a refresh token to .mcp.json automatically:

npx @oxygenbubbles/freeagent-mcp-server auth

The command prompts for your Client ID and Client Secret, opens the FreeAgent authorization page in your browser, listens for the callback, exchanges the code for a long-lived refresh token, and writes everything to .mcp.json in the current directory. If .mcp.json already exists, it updates just the freeagent entry.

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Installation

git clone https://github.com/OxygenBubbles/freeagent-mcp-server.git
cd freeagent-mcp-server
npm install
npm run build

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Configuration

All settings are read from environment variables.

Required

Variable	Description
FREEAGENT_CLIENT_ID	OAuth client ID
FREEAGENT_CLIENT_SECRET	OAuth client secret
FREEAGENT_REFRESH_TOKEN	Long-lived refresh token

Optional

Variable	Description
VENDOR_CATEGORIES	JSON object extending the built-in vendor → category mapping (see below)
MILEAGE_CATEGORY_URL	FreeAgent category URL for mileage expenses (default /v2/categories/249, the standard Mileage category)
MILEAGE_RATE_PENCE	Fallback pence-per-mile rate for the estimate, used only when FreeAgent's own mileage settings cannot be read
HMRC_RATE_HIGH_PENCE	HMRC high-band rate in pence, used as a last-resort fallback (default 45)
HMRC_RATE_LOW_PENCE	HMRC low-band rate in pence, used as a last-resort fallback (default 25)
HMRC_THRESHOLD_MILES	Miles per tax year before the low band kicks in (default 10000)
ORS_API_KEY	OpenRouteService API key for drive-distance lookups
GOOGLE_MAPS_API_KEY	Google Maps API key for drive-distance lookups (alternative to ORS)
PORT	If set, serves over HTTP on this port instead of stdio
FREEAGENT_ATTACHMENT_ROOTS	Colon-separated directories that filePath attachments may be read from. Required for local paths in HTTP mode; optional (and recommended) over stdio
AUTH_TOKEN	Bearer token required on every HTTP request. Strongly recommended whenever PORT is set
FREEAGENT_DEBUG	Set to 1 to log every request and error response to stderr. Tokens, credentials and file payloads are redacted

Built-in vendor → category mappings

The server ships with mappings for common vendors, using FreeAgent's standard UK nominal codes:

• Web Hosting (268) — IONOS, AWS, Netlify, Vercel, Heroku, DigitalOcean, Cloudflare
• Computer Software (269) — OpenAI, Anthropic, GitHub, Stripe, Google, Microsoft, Zoom, Notion, Dropbox, Slack, Adobe, Fastmail, Mailchimp
• Accommodation and Meals (285) — Booking.com, Hotels.com, Premier Inn, Travelodge, Airbnb
• Travel (365) — Trainline, LNER, Uber

Check these against your own chart of accounts with freeagent_list_categories — nominal codes can be customised per account. Override or extend via VENDOR_CATEGORIES:

VENDOR_CATEGORIES='{"ACME CORP":"/v2/categories/285","NETFLIX":"/v2/categories/269"}'

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Claude Desktop setup

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "freeagent": {
      "command": "node",
      "args": ["/path/to/freeagent-mcp-server/dist/index.js"],
      "env": {
        "FREEAGENT_CLIENT_ID": "...",
        "FREEAGENT_CLIENT_SECRET": "...",
        "FREEAGENT_REFRESH_TOKEN": "..."
      }
    }
  }
}

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Usage examples

List my unexplained Starling transactions for April 2026

Approve explanation 12345678 and attach the receipt at ~/Downloads/invoice.pdf

Create an expense for the £22.80 IONOS charge on 3 April, rebilled to the Example Client project at cost — the receipt is at ~/Desktop/ionos.png

That IONOS expense should be Reverse Charge, not UK/Non-EC — fix it

Log 24 miles for a client visit from the office to a customer site on 10 April

Add a line to draft invoice 4471 for 2 days' consultancy at £650

Which April expenses are tagged to a project but not set to rebill?

Show me everything queued to bill on to Example Client that isn't on an invoice yet

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Mileage rates

Mileage is a special FreeAgent category: you submit the miles and vehicle type, and FreeAgent calculates the claim value from the mileage rate configured on the account. That figure is what appears in your accounts and HMRC reporting, so the server does not attempt to override it.

The estimate returned alongside the filed amount uses that same rate: the server reads GET /v2/expenses/mileage_settings and applies the band published for the journey's date and vehicle. The response records where the rate came from in estimateSource:

estimateSource	Meaning
freeagent_mileage_settings	The account's own published rate — the normal case
argument	A ratePence you passed explicitly, which always wins
MILEAGE_RATE_PENCE	Settings could not be read; the environment variable was used
hmrc_defaults	Settings could not be read and no override was set; the built-in HMRC bands were used

The last two are fallbacks, and the response says so in notes. When the estimate and the filed amount still differ, that is worth a look:

FreeAgent filed £46.20 using the mileage rate configured on the account; the estimate from 84 miles @ 45p/mile (FreeAgent mileage settings) was £37.80.

HMRC's approved rates are 45p/mile for the first 10,000 business miles in the tax year and 25p above it, and anything paid above the approved rate is a taxable benefit.

To reclaim the VAT on the fuel element, pass engineType and engineSize (and haveVatReceipt) — FreeAgent cannot calculate it without them.

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Development

npm run dev        # watch mode (tsx)
npm run build      # compile TypeScript → dist/
npm start          # run compiled server
npm test           # run unit tests once
npm run test:watch # watch mode for tests

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Claude Code setup

Create .mcp.json in your project directory (or ~/.mcp.json for global access):

{
  "mcpServers": {
    "freeagent": {
      "command": "node",
      "args": ["/path/to/freeagent-mcp-server/dist/index.js"],
      "env": {
        "FREEAGENT_CLIENT_ID": "...",
        "FREEAGENT_CLIENT_SECRET": "...",
        "FREEAGENT_REFRESH_TOKEN": "..."
      }
    }
  }
}

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HTTP mode

Set PORT to run as an HTTP server (for webhooks, iPhone Shortcuts, Power Automate):

PORT=3000 AUTH_TOKEN=a-long-random-string node dist/index.js

Always set AUTH_TOKEN when exposing HTTP mode — every request must include Authorization: Bearer <AUTH_TOKEN> or it is rejected with 401. Without AUTH_TOKEN the server starts anyway but prints a warning to stderr and accepts all requests; only do that on a trusted loopback interface.

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Security

• Credentials are environment variables, never in code
• FreeAgent tokens are cached in memory and refreshed automatically
• Transactions are never approved without a confirmed receipt or explicit instruction
• The server never creates new categories — only selects from existing ones
• Receipt URLs are fetched through an SSRF guard: the address validated is the address dialled, every redirect hop is re-checked, proxies are bypassed and downloads are size-capped
• Local receipt paths must be absolute and are resolved through symlinks before use; in HTTP mode they are refused unless FREEAGENT_ATTACHMENT_ROOTS names the directories that may be read
• The three deletes whose loss is unrecoverable — expenses, contacts and projects — require confirm: true in addition to the client's own prompt
• .mcp.json is excluded from git via .gitignore

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Licence

MIT