Billit API

Name: Billit API
Brand: Billit API
Availability: InStock

★ Only Publicly Available OpenAPI DocumentFinanceAccountingapiKey4 EndpointsREST

For Agents

List and create invoices and pull customer and expense records from the Billit invoicing and accounting platform.

Install Jentic One Beta

Connect the Billit API to your agent

Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Billit API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.

Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.

Step 1: Jentic One Host machine

# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh

Step 2: Agent machine

# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register       # connects your agent to your Jentic One instance

Jentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.

Capabilities

What an agent can do with Billit API.

Create new invoices in Billit with customer, line item, and amount data

List existing invoices to drive dashboards or downstream reconciliation

Retrieve the customer list to populate dropdowns or sync with external CRMs

GET STARTED

Start building with Billit API

Explore with Jentic

View OpenAPI Document

Use Cases

Patterns agents use Billit API for, with concrete tasks.

★ Programmatic Invoice Creation

Service businesses and SaaS companies want to issue invoices automatically when a job completes or a billing cycle closes. The Billit API exposes POST /invoices for creation and GET /invoices for retrieval, so a billing job can issue a new invoice and confirm it was recorded in a single round trip. Integration is typically a half day for a basic create-and-confirm flow.

Create an invoice for customer Acme Ltd with one line item of 500 EUR via POST /invoices, then list invoices and confirm the new one is present.

Customer Sync to a CRM

Operations teams want their CRM and invoicing tool to share the same customer list so sales activity matches billing records. The Billit API provides GET /customers to pull all customers, which a nightly job can compare against a CRM and reconcile differences. Setup is usually one day for a one-way sync.

Pull the full customer list from GET /customers and upsert each record into a HubSpot company list.

Expense Reporting Pipeline

Finance teams run weekly expense reports that combine multiple sources. The Billit API exposes GET /expenses, allowing a scheduled job to pull recent expenses and feed them into a BI tool or accounting software. Setup is half a day for a single feed, and the small endpoint surface keeps maintenance light.

Pull all expenses from GET /expenses and write each record as a row in a Google Sheet for the weekly finance review.

AI Agent Invoicing Assistant via Jentic

An AI assistant for self-employed users can create invoices and pull expense or customer records via natural-language requests routed through Jentic. The API key is stored in the Jentic vault, so the assistant never sees the raw secret, and Jentic returns the right Billit operation when the user asks something like "create an invoice for Acme for 500 euros". Setup through Jentic takes under an hour.

Search Jentic for 'create an invoice in Billit', load the POST /invoices schema, and execute it with a one-line invoice for 500 EUR to a named customer.

Key Endpoints

4 endpoints — jentic publishes the only available openapi specification for billit api, keeping it validated and agent-ready.

METHOD

PATH

DESCRIPTION

POST

/invoices

Create a new invoice

GET

/invoices

List all invoices

GET

/customers

List all customers

GET

/expenses

List all expenses

POST

/invoices

Create a new invoice

GET

/invoices

List all invoices

GET

/customers

List all customers

GET

/expenses

List all expenses

Why Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

Billit API keys are stored encrypted in the Jentic vault (MAXsystem). Agents receive scoped access tokens — the raw Authorization key never enters the agent's context or logs.

Intent-based discovery

Agents search by intent (e.g., 'create an invoice in Billit') and Jentic returns the matching Billit operation with its input schema, so the agent can call POST /invoices without browsing third-party docs.

Time to first call

Direct Billit integration: 1-2 days for invoice creation, customer sync, and expense pulls. Through Jentic: under 1 hour — search, load schema, execute.

FAQs

Specific to using Billit API through Jentic.

Why is there no official OpenAPI spec for Billit API?

Billit does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Billit API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.

What authentication does the Billit API use?

The Billit API uses an API key in the Authorization header. You generate the key from the Billit dashboard. When called via Jentic, the key is held in the MAXsystem vault so the raw Authorization value never reaches the agent's context.

Can I create invoices with the Billit API?

Yes. POST /invoices creates a new invoice from a JSON body. GET /invoices lists existing invoices, which is the recommended way to confirm a freshly created record was persisted.

What are the rate limits for the Billit API?

The current spec does not declare explicit numeric rate limits. Treat 429 responses as the signal to back off, and call the Jentic SDK, which retries on 429 with exponential back-off so high-volume jobs do not have to handle this by hand.

How do I create an invoice through Jentic?

Search Jentic for 'create an invoice in Billit', which surfaces POST /invoices. Load the schema, supply customer and line-item data, and execute. The Python flow is: pip install jentic, then await client.search, await client.load, await client.execute.

Can I list customers and expenses through the Billit API?

Yes. GET /customers returns all customers and GET /expenses returns all expenses. These two endpoints are read-only in the current spec, suitable for sync jobs and reporting pipelines but not for editing customer or expense records.

Billit API

Connect the Billit API to your agent

Capabilities

Start building with Billit API

Use Cases

Key Endpoints

Why Jentic?

Related APIs

FAQs