Freshbooks MCP Server

freshbooks-mcp

MCP server for FreshBooks — invoices, clients, estimates and payments, exposed to Claude as typed tools.

This project was developed and is maintained by AI (Claude Code). Use at your own discretion.

Install

npm install -g @chrischall/freshbooks-mcp

Setup

FreshBooks is OAuth2 only — there is no API key and no personal access token, so a one-time browser authorization is required.

1. Register an app at https://my.freshbooks.com/#/developer. The redirect URI must be HTTPS with no query string; https://localhost works and never needs to resolve.
2. Note the Client ID and Client Secret.
3. Obtain a refresh token, either way:
   • From the server itself (no script): set FRESHBOOKS_CLIENT_ID and FRESHBOOKS_CLIENT_SECRET, start it, then call freshbooks_auth_url, open the URL it returns, approve, and pass the URL you land on to freshbooks_auth_exchange. Those two tools need no refresh token — minting one is what they are for. This is also the path mcp-host's authFlow drives, so a hosted connector can do it without you pasting anything.
   • From the script, if you prefer it outside the server — see skills/freshbooks-curl.
4. Configure:

FRESHBOOKS_CLIENT_ID=...
FRESHBOOKS_CLIENT_SECRET=...
FRESHBOOKS_REFRESH_TOKEN=...       # from the bootstrap
FRESHBOOKS_REDIRECT_URI=https://localhost   # optional; must match what you registered
FRESHBOOKS_TOKEN_STORE=~/.freshbooks-mcp/session.json   # optional

⚠️ Refresh tokens rotate

FreshBooks issues a new refresh token on every refresh and immediately invalidates the old one. This server persists each rotation to FRESHBOOKS_TOKEN_STORE (mode 0600) before the refresh is considered complete, and prefers the stored token over the environment value — the stored one has rotated past it.

Two consequences worth knowing:

• Do not point two tools at the same store. The MCP server and the freshbooks-curl skill keep separate state files on purpose; sharing one makes them spend each other's tokens and locks both out.
• If the store is lost, re-run the bootstrap. A spent refresh token cannot be recovered.

Changing FRESHBOOKS_REFRESH_TOKEN to a freshly bootstrapped value is detected and adopted, so re-bootstrapping is the supported recovery path.

Tools

Confirm-gated means the tool makes no network call unless confirm: true is passed; without it you get a dry-run preview of exactly what would be sent.

Estimate writes

Acceptance is an action on the estimate, not a status field: status (int), display_status and ui_status are computed and read-only, and they disagree with each other by design (a viewed estimate reads status: 3, display_status: "viewed", ui_status: "open"). Accepting is PUT estimates/estimates/{id} with {"estimate": {"action_accept": true}} — see docs/FRESHBOOKS-API.md for where that shape comes from.

• Accept is idempotent. An estimate already accepted (or invoiced) comes back with changed: false and no write is sent — acceptance cannot be undone through the API, so a repeat call must not re-fire it.
• There is no decline. FreshBooks' estimate statuses are draft / sent / viewed / replied / accepted / invoiced; no declined state, no action_deny, no estimate.decline webhook. freshbooks_decline_estimate exists only to say so and point at the alternatives, rather than leave an agent to invent a write that changes nothing.
• Every write returns the re-fetched estimate, plus before / after state and changed / changedFields, so success is verified against the record rather than inferred from a 200. changed covers the status fields and the fields that write actually set, so a successful notes edit reports changed: true even though no status moves. On freshbooks_send_estimate it describes the record only — emailing an already-sent estimate moves nothing, and retrying on changed: false would send the client a second copy.

Writes require an owner/admin accounting account

FreshBooks separates the role you hold on a business from the role you hold on an accounting account. You can own a business that has no accounting account (account_id: null) while being only a client on the account you can actually see — in which case reads succeed and every write returns 403 Permission Denied, even though your OAuth token carries all the :write scopes.

freshbooks_get_identity reports accountRole and businessRole so this is visible up front. If accountRole is client, the invoicing write tools will not work against that account — that is an account permission, not a configuration problem.

Two things the API reports misleadingly

• total counts records you may not be able to read. Expenses reported total: 16 while returning zero rows. List results attach a note when that happens, so it reads as a permission boundary rather than an empty account.
• Projects and time tracking are keyed by businessId, not accountId, and paginate under a meta block instead of flat page/pages/total. They also work on a business with no accounting account at all.

The three identifiers

FreshBooks hands out three non-interchangeable ids, and using the wrong one returns a bare 404 that reads like a missing record:

Call freshbooks_get_identity first. Full API notes, including the four different error envelopes, are in docs/FRESHBOOKS-API.md.

Shell access without the server

skills/freshbooks-curl covers the same API from a shell with curl + jq, including the OAuth bootstrap and rotation-safe token handling.

Development

npm install
npm run build
npm test

License

MIT