# BillingEngine

**Canonical:** https://apis.io/providers/billingengine/  
**Website:** https://www.billingengine.com/  
**APIs profiled:** 1

BillingEngine provides online invoicing software tailored for freelancers and small businesses in Germany. Its REST API enables listing, creating, and updating customers and draft invoices, recording payments, and downloading invoices as PDF or XML e‑invoices (ZUGFeRD / XRechnung, EN 16931). The platform also offers an MCP server for AI assistants, requiring an API key from a paid plan.

## Kin Score — 47.2 / 100 (developing)

Scored 2026-10-23 under rubric 0.25.0.

| Facet | Score |
|---|---|
| Discoverability | 56.7 |
| Contract Quality | 65.6 |
| Contract Governance | 35.6 |
| Operational Transparency | 5.3 |
| Developer Ergonomics | 30.4 |
| Access Clarity | 63.2 |

Regulatory layer — **Horizontal (data, software, accessibility, platform)**: 24.5 (matched via fallback).

## Agent readiness — 26.6 (agent-aware)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | documented |
| Auth Clarity | bearer |
| Idempotency | no |
| Error Semantics | derived |
| OpenAPI Examples | no |
| Rate Limit Signal | no |
| Event Surface Described | no |
| Agent Skills | derived |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |
| Pagination Ratio | paginated |
| Operation Distinctiveness | distinct |

## APIs (3)

- **BillingEngine Customers API** — Customers of the account.
- **BillingEngine Invoices API** — Invoices, created as drafts, and their PDF and XML e-invoice downloads.
- **BillingEngine Payments API** — Payments received for sent invoices.

## MCP servers (1)

- **BillingEngine MCP Server**

## Agentic access (1)

- **Billingengine Agentic Access** — 12 operations · 5 acting

## Security (2)

- **Billingengine Authentication** — http · 1 scheme
- **Billingengine Domain Security** — TLSv1.3 · HSTS · DMARC

## Plans (1)

- **Billingengine Plans Pricing**

## Tags

Invoicing, Fintech, Germany, Small Business

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/billingengine/). Scores are computed from the provider's own public artifacts under a published rubric.