Accounting Providers

The AI Accountant supports multiple accounting systems through a provider abstraction. Each provider implements IAccountingProvider, allowing the Core API to work identically regardless of the underlying system.

Architecture

Core API (AgentManager)
    │
    ├── IAccountingProvider
    │       ├── TripletexProvider  ──REST──→  Tripletex API v2
    │       └── FikenProvider      ──REST──→  Fiken API v2
    │
    └── Provider resolved per company at runtime

IAccountingProvider Interface

The interface defines all accounting operations the system needs. Each provider implements what it can; unsupported operations return a structured NotSupported result.

Customer Management

Method	Description	Parameters
CreateCustomer	Create a new customer	name, organizationNumber?, email?, phoneNumber?, postalAddress?
UpdateCustomer	Update customer fields	id, fields to update
SearchCustomers	Search by name or org number	query, limit?

Invoice Operations

Method	Description	Parameters
CreateInvoice	Create a customer invoice	customerId, invoiceDate, dueDate, lines[]
SendInvoice	Send invoice via email/EHF	invoiceId, sendType
CreateCreditNote	Credit an existing invoice	invoiceId, comment
GetInvoice	Get invoice by ID	id
SearchInvoices	Search invoices	customerId?, isSent?, isOverdue?, dateFrom?, dateTo?

Supplier Invoice Operations

Method	Description	Parameters
CreateSupplierInvoice	Register a supplier invoice	supplierId, invoiceNumber, invoiceDate, dueDate, postings[]
RegisterPayment	Register payment on supplier invoice	id, paymentDate, bankAccountId
SearchSupplierInvoices	Search supplier invoices	supplierId?, isDue?, isPaid?, dateFrom?, dateTo?

Supplier Management

Method	Description	Parameters
CreateSupplier	Create a new supplier	name, organizationNumber?, bankAccount?, email?
SearchSuppliers	Search suppliers	query, organizationNumber?

Voucher / Journal Entry Operations

Method	Description	Parameters
CreateVoucher	Create a general ledger voucher	date, description, postings[]
SearchVouchers	Search vouchers	dateFrom, dateTo, description?

Employee and Salary

Method	Description	Parameters
GetEmployees	List active employees	departmentId?
CreateTravelExpense	Create a travel expense	employeeId, travelDetails, costs[]
CreatePayslip	Create a salary payslip	employeeId, year, month, specifications[]
GetTimesheetEntries	Get timesheet data	employeeId?, dateFrom, dateTo

Ledger Queries

Method	Description	Parameters
GetLedgerPostings	Query general ledger	accountFrom?, accountTo?, dateFrom, dateTo
GetTrialBalance	Get trial balance	dateFrom, dateTo, departmentId?

Bank Operations

Method	Description	Parameters
CreateBankReconciliation	Reconcile a bank transaction	bankStatementId, matchedInvoiceId?, amount
GetBankStatements	Get bank statements	dateFrom, dateTo

Context / Reference Data

Method	Description
GetCompanyInfo	Company name, org number, fiscal year
GetChartOfAccounts	Active accounts with number, name, VAT type
GetDepartments	Department list with IDs
GetVatTypes	VAT codes and percentages

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Provider Comparison

Feature	Tripletex	Fiken
Customer CRUD	Yes	Yes
Invoice create/send	Yes	Yes
Supplier invoice	Yes	Yes
Register payment	Yes	Yes
Voucher / journal entry	Yes	Yes
Employee management	Yes	No
Travel expense	Yes	No
Salary / payroll	Yes	No
Bank reconciliation	Yes	Limited
Ledger queries	Yes	Yes
Trial balance	Yes	Yes
Department filtering	Yes	No
Project tracking	Yes	No
EHF (e-invoice)	Yes	Yes
Multi-currency	Yes	Limited
Auth method	OAuth2 + session tokens	OAuth2 (bearer token)
Rate limit	100 req/s per company	120 req/min per token
Base URL	https://tripletex.no/v2	https://api.fiken.no/api/v2
Pricing	Varies by plan	99 NOK/month

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TripletexProvider

Implements the full IAccountingProvider interface. Tripletex is a comprehensive ERP with deep support for salary, travel expenses, project tracking, and departments.

Authentication: OAuth2 consumer token + employee token, exchanged for session tokens (1-hour TTL, auto-refresh). All API calls use Basic Auth with the session token.

Rate limiting: Token bucket at 80 req/s (below the 100 req/s hard limit), retry with exponential backoff on 429.

Key endpoints: See Tripletex API reference.

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FikenProvider

Implements core accounting operations from IAccountingProvider. Fiken is a simpler system focused on invoicing, bookkeeping, and VAT reporting for small businesses.

Authentication: OAuth2 with bearer tokens. Standard authorization code flow.

Rate limiting: 120 requests per minute per access token. Retry with backoff on 429.

Unsupported operations: Employee management, travel expenses, salary/payroll, department filtering, project tracking. These methods return NotSupported and the agent informs the user.

Key endpoints:

Category	Endpoints
Contacts	GET/POST /companies/{companySlug}/contacts
Invoices	GET/POST /companies/{companySlug}/invoices
Credit Notes	POST /companies/{companySlug}/credit-notes
Purchases	GET/POST /companies/{companySlug}/purchases
Payments	POST /companies/{companySlug}/payments
Journal Entries	GET/POST /companies/{companySlug}/journal-entries
Accounts	GET /companies/{companySlug}/accounts
Bank Accounts	GET /companies/{companySlug}/bank-accounts

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Error Handling

Both providers translate API errors into structured results:

Condition	Result	Agent Action
Validation error (400)	ValidationError with field details	Fix fields and retry
Auth error (401)	AuthError	Refresh token, retry
Not found (404)	NotFound with entity type	Search for correct entity
Business rule violation (422)	BusinessError with message	Interpret error, adjust approach
Rate limited (429)	RateLimited with retry-after	Wait and retry
Unsupported operation	NotSupported with explanation	Inform user, suggest alternative

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Configuration

Provider selection is per-company, stored in the company configuration:

// Resolved at runtime based on company settings
IAccountingProvider provider = providerFactory.GetProvider(companyId);
// Returns TripletexProvider or FikenProvider