> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gobl.org/llms.txt
> Use this file to discover all available pages before exploring further.

# GOBL API

> Build, validate, sign, and query tax-aware business documents via REST

The [GOBL API](https://gobl.dev) provides a hosted REST service for working with GOBL documents without needing to install or run any libraries locally. It's ideal for integrations in any language.

Base URL:

```
https://gobl.dev/v0
```

## Endpoints

The API is organized into three groups:

* **Documents** — [Build](/api/documents/build), [validate](/api/documents/validate), [correct](/api/documents/correct), and [replicate](/api/documents/replicate) GOBL documents.
* **Signing** — [Sign](/api/signing/sign) and [verify](/api/signing/verify) envelopes, or [generate key pairs](/api/signing/keygen).
* **Reference** — Query available [JSON schemas](/api/reference/list-schemas), [tax regimes](/api/reference/list-regimes), and [addons](/api/reference/list-addons).

## Quick Example

Build and validate an invoice in a single request:

```bash theme={"system"}
curl -X POST https://gobl.dev/v0/build \
  -H "Content-Type: application/json" \
  -d '{
    "data": {
      "$schema": "https://gobl.org/draft-0/bill/invoice",
      "series": "EXAMPLE",
      "currency": "USD",
      "issue_date": "2024-01-15",
      "supplier": {
        "name": "Seller Co.",
        "tax_id": { "country": "US" }
      },
      "customer": {
        "name": "Buyer Inc.",
        "tax_id": { "country": "US" }
      },
      "lines": [
        {
          "quantity": "1",
          "item": {
            "name": "Service",
            "price": "100.00"
          }
        }
      ]
    }
  }'
```

No authentication is required. The API is free to use.

## MCP Server

An [MCP (Model Context Protocol) server](/api/mcp) is also available for integrating GOBL with AI assistants like Claude. It exposes the same document operations plus tax reference data as MCP tools.