Fjordbook MCP: Model Context Protocol Server for Fiken Accounting API

A Model Context Protocol (MCP) server that connects AI assistants like Claude and Cursor to the Fiken accounting API. Manage invoices, contacts, purchases, journal entries, and more — directly from your AI assistant.

Mutating tools are annotated so MCP clients can require your approval before they run (see Safety).

Fjordbook started as a fork of gronnmann/fiken-mcp and has since been extended and hardened into a separate project (full API coverage, safer client, toolset filtering, live smoke test).

Quick start

1. Create a personal API token in Fiken (Profile → API → Personal tokens) and note your company slug (fiken.no/company/YOUR-SLUG/...).
2. Add the server to your MCP client. Example for Claude Desktop (claude_desktop_config.json):

{
    "mcpServers": {
        "fjordbook": {
            "command": "npx",
            "args": ["-y", "fjordbook-mcp"],
            "env": {
                "FIKEN_API_TOKEN": "your-personal-token-here",
                "FIKEN_COMPANY_SLUG": "your-company-slug"
            }
        }
    }
}

3. Restart the client and ask: "List my Fiken contacts".

Requires Node.js 18.17 or newer. Setup for Claude Code, Cursor, VS Code, Windows and local models, plus troubleshooting, is in the installation guide.

Features

• Invoices & Credit Notes: Create, send, and manage invoices and credit notes with full draft support
• Contacts: Full CRUD for customers and suppliers, including contact persons
• Purchases & Sales: Record and manage purchases and sales transactions
• Offers & Order Confirmations: Create and send offers, convert to invoices
• Accounting: Bookkeeping accounts, bank accounts, journal entries, transactions
• Reports: Product sales reports, account balances
• Time Tracking: Projects, time entries, activities, team members
• Complete API coverage: Payments, accruals, recurring invoices, products, attachments, inbox and EHF documents
• Reliable client: One request at a time (Fiken rate limit), timeouts, safe retries, pagination info on list results

Configuration

FIKEN_API_TOKEN and FIKEN_COMPANY_SLUG are required. Optional variables:

| Variable | Default | Purpose | | :----------------------- | :--------- | :-------------------------------------------------------------------- | | FIKEN_TIMEOUT_MS | 30000 | Per-request timeout | | FIKEN_TOOLSETS | all | Comma-separated toolsets to expose (see below); user is always on | | FIKEN_UPLOAD_ROOT | unset | If set, attachment uploads by file path must be inside this directory | | FIKEN_MAX_UPLOAD_BYTES | 26214400 | Maximum attachment size (25 MB) |

All 189 tools take roughly 47k tokens of context, too much for small local models. Set FIKEN_TOOLSETS to expose a subset, e.g. FIKEN_TOOLSETS=contacts,products (19 tools including user). Valid names: user, accounts, contacts, invoices, creditNotes, offers, orderConfirmations, journalEntries, transactions, purchases, sales, misc, recurringInvoices, products, timeTracking, attachments. Unknown names abort startup with an error.

Uploads by path are restricted to regular .pdf/.png/.jpg/.gif files whose content matches the extension; hidden directories (~/.ssh, ~/.aws, ...) and system directories are refused unless FIKEN_UPLOAD_ROOT allows them.

Available Tools

189 tools covering every operation of the Fiken API v2 (verified against the official OpenAPI spec by the test suite).

| Category | Tools | | :--------------------------------- | :---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | User (3) | fiken_get_user, fiken_list_companies, fiken_get_company | | Accounts & Bank (8) | fiken_list_accounts, fiken_get_account, fiken_list_account_balances, fiken_get_account_balance, fiken_list_bank_accounts, fiken_create_bank_account, fiken_get_bank_account, fiken_list_bank_balances | | Contacts (11) | fiken_list_contacts, fiken_create_contact, fiken_get_contact, fiken_update_contact, fiken_delete_contact, fiken_list_contact_persons, fiken_create_contact_person, fiken_get_contact_person, fiken_update_contact_person, fiken_delete_contact_person, fiken_list_groups | | Invoices (16) | fiken_list_invoices, fiken_create_invoice, fiken_get_invoice, fiken_update_invoice, fiken_get_invoice_attachments, fiken_send_invoice, fiken_get_invoice_counter, fiken_create_invoice_counter, fiken_list_invoice_drafts, fiken_create_invoice_draft, fiken_get_invoice_draft, fiken_update_invoice_draft, fiken_delete_invoice_draft, fiken_get_invoice_draft_attachments, fiken_create_recurring_invoice_from_draft, fiken_create_invoice_from_draft | | Recurring Invoices (11) | fiken_list_recurring_invoices, fiken_create_recurring_invoice, fiken_get_recurring_invoice, fiken_update_recurring_invoice_lines, fiken_update_recurring_invoice_frequency, fiken_add_recurring_invoice_job, fiken_update_recurring_invoice_job_schedule, fiken_update_recurring_invoice_job_recipients, fiken_pause_recurring_invoice_job, fiken_resume_recurring_invoice_job, fiken_stop_recurring_invoice_job | | Credit Notes (14) | fiken_list_credit_notes, fiken_get_credit_note, fiken_create_full_credit_note, fiken_create_partial_credit_note, fiken_send_credit_note, fiken_get_credit_note_counter, fiken_create_credit_note_counter, fiken_list_credit_note_drafts, fiken_create_credit_note_draft, fiken_get_credit_note_draft, fiken_update_credit_note_draft, fiken_delete_credit_note_draft, fiken_get_credit_note_draft_attachments, fiken_create_credit_note_from_draft | | Offers (12) | fiken_list_offers, fiken_get_offer, fiken_get_offer_counter, fiken_create_offer_counter, fiken_list_offer_drafts, fiken_create_offer_draft, fiken_get_offer_draft, fiken_update_offer_draft, fiken_delete_offer_draft, fiken_get_offer_draft_attachments, fiken_create_offer_from_draft, fiken_send_offer | | Order Confirmations (11) | fiken_list_order_confirmations, fiken_get_order_confirmation, fiken_get_order_confirmation_counter, fiken_create_order_confirmation_counter, fiken_create_invoice_draft_from_order_confirmation, fiken_list_order_confirmation_drafts, fiken_create_order_confirmation_draft, fiken_get_order_confirmation_draft, fiken_update_order_confirmation_draft, fiken_delete_order_confirmation_draft, fiken_create_order_confirmation_from_draft | | Products (5) | fiken_list_products, fiken_create_product, fiken_get_product, fiken_update_product, fiken_delete_product | | Purchases (21) | fiken_list_purchases, fiken_create_purchase, fiken_get_purchase, fiken_delete_purchase, fiken_get_purchase_attachments, fiken_add_purchase_attachment, fiken_list_purchase_drafts, fiken_create_purchase_draft, fiken_get_purchase_draft, fiken_update_purchase_draft, fiken_delete_purchase_draft, fiken_get_purchase_draft_attachments, fiken_create_purchase_from_draft, fiken_get_purchase_payments, fiken_create_purchase_payment, fiken_get_purchase_payment, fiken_delete_purchase_payment, fiken_get_purchase_accruals, fiken_create_purchase_accrual, fiken_get_purchase_accrual, fiken_delete_purchase_accrual | | Sales (22) | fiken_list_sales, fiken_create_sale, fiken_get_sale, fiken_delete_sale, fiken_get_sale_attachments, fiken_list_sale_drafts, fiken_create_sale_draft, fiken_get_sale_draft, fiken_update_sale_draft, fiken_delete_sale_draft, fiken_get_sale_draft_attachments, fiken_create_sale_from_draft, fiken_settle_sale, fiken_write_off_sale, fiken_get_sale_payments, fiken_create_sale_payment, fiken_get_sale_payment, fiken_delete_sale_payment, fiken_get_sale_accruals, fiken_create_sale_accrual, fiken_get_sale_accrual, fiken_delete_sale_accrual | | Journal Entries (4) | fiken_list_journal_entries, fiken_get_journal_entry, fiken_get_journal_entry_attachments, fiken_create_journal_entry | | Transactions (3) | fiken_list_transactions, fiken_get_transaction, fiken_delete_transaction | | Attachments (23) | fiken_add_contact_attachment, fiken_delete_contact_attachment, fiken_add_invoice_attachment, fiken_delete_invoice_attachment, fiken_add_invoice_draft_attachment, fiken_delete_invoice_draft_attachment, fiken_add_credit_note_draft_attachment, fiken_delete_credit_note_draft_attachment, fiken_add_journal_entry_attachment, fiken_delete_journal_entry_attachment, fiken_add_offer_draft_attachment, fiken_delete_offer_draft_attachment, fiken_add_order_confirmation_draft_attachment, fiken_delete_order_confirmation_draft_attachment, fiken_add_purchase_draft_attachment, fiken_delete_purchase_draft_attachment, fiken_add_sale_draft_attachment, fiken_delete_sale_draft_attachment, fiken_add_sale_attachment, fiken_delete_sale_attachment, fiken_delete_purchase_attachment, fiken_get_contact_attachments, fiken_get_order_confirmation_draft_attachments | | Time Tracking & Projects (18) | fiken_list_projects, fiken_create_project, fiken_get_project, fiken_update_project, fiken_delete_project, fiken_list_activities, fiken_create_activity, fiken_get_activity, fiken_update_activity, fiken_delete_activity, fiken_list_time_entries, fiken_create_time_entry, fiken_create_invoice_draft_from_time_entries, fiken_get_time_entry, fiken_update_time_entry, fiken_delete_time_entry, fiken_list_time_users, fiken_get_time_user | | Misc (reports, inbox, EHF) (7) | fiken_create_product_sales_report, fiken_list_inbox, fiken_create_inbox_document, fiken_get_inbox_document, fiken_delete_inbox_document, fiken_list_ehf_documents, fiken_get_ehf_document |

Note: Amounts are in NOK øre (1/100 of a krone). Dates use YYYY-MM-DD format.

Safety

• Every tool carries MCP annotations: read-only tools are marked readOnlyHint, and deletes and full-record replacements (PUT updates) are marked destructiveHint, so clients can ask for approval before mutations.
• send_invoice, send_offer and send_credit_note email real recipients. Review before approving them.
• The token grants access to every company your Fiken user can reach. Use a dedicated token, pin FIKEN_COMPANY_SLUG to one company, and try new workflows on a demo company first.
• Uploads by path are restricted (see above). Tool inputs are schema-validated: ids cannot traverse to other endpoints, dates must be YYYY-MM-DD.
• This is an unofficial project, not affiliated with or endorsed by Fiken AS, and it was built with the help of Claude Code. Use at your own risk.

Documentation

• Installation guide: all clients, Windows, local models, troubleshooting
• Development: build, test, live smoke test, release flow
• Architecture: modules, conventions, client behaviour, spec conformance

License

MIT, see LICENSE.