JSON schema: extract a U.S. invoice

JSON Schema to extract a U.S. invoice with an LLM: vendor, invoice number, dates, line items, subtotal, sales tax and total in USD.

Extract the invoice data. Amounts are plain numbers in U.S. dollars, without the $ sign. If a field is missing, leave it out: never invent it.

JSON Schema

{
  "type": "object",
  "required": [
    "vendor",
    "invoice_date",
    "total"
  ],
  "properties": {
    "total": {
      "type": "number"
    },
    "vendor": {
      "type": "string",
      "description": "Legal name of the vendor"
    },
    "currency": {
      "enum": [
        "USD"
      ],
      "type": "string"
    },
    "due_date": {
      "type": "string",
      "format": "date"
    },
    "subtotal": {
      "type": "number"
    },
    "sales_tax": {
      "type": "number",
      "description": "Sales tax amount, 0 if none"
    },
    "line_items": {
      "type": "array",
      "items": {
        "type": "object",
        "required": [
          "description",
          "amount"
        ],
        "properties": {
          "amount": {
            "type": "number"
          },
          "quantity": {
            "type": "number"
          },
          "unit_price": {
            "type": "number"
          },
          "description": {
            "type": "string"
          }
        }
      }
    },
    "invoice_date": {
      "type": "string",
      "format": "date",
      "description": "Issue date (YYYY-MM-DD)"
    },
    "invoice_number": {
      "type": "string"
    }
  }
}

Output example

{
  "vendor": "Bright Print Co.",
  "invoice_number": "INV-2026-0412",
  "invoice_date": "2026-09-15",
  "due_date": "2026-10-15",
  "line_items": [
    {
      "description": "Business cards x500",
      "quantity": 1,
      "unit_price": 80.0,
      "amount": 80.0
    },
    {
      "description": "Flyers 5.5x8.5 x1000",
      "quantity": 1,
      "unit_price": 120.0,
      "amount": 120.0
    }
  ],
  "subtotal": 200.0,
  "sales_tax": 17.25,
  "total": 217.25,
  "currency": "USD"
}

Estimated cost

Input tokens per call : ≈ 656

Input cost only, excluding the model's answer. Providers' public standard prices (Mistral AI, DeepSeek, OpenAI, Anthropic) converted from USD to euros at the ECB rate of September 29, 2026. Estimate: 1 token ≈ 3.6 characters.

Identifier

contextetech--extract-us-invoice

Type

Output schemas

File

extract-us-invoice.schema.json

Format

JSON (application/json)

Size

1,215 bytes (1.2 KB)

Encoding

UTF-8

Estimated tokens

≈ 338

Language

English

License

MIT

Commercial use

Allowed

Personal data

None

Version

1.0

Published on

October 2, 2026 at 9:54 PM

Updated on

October 2, 2026 at 9:54 PM

Storage

in database

Uses

0

Likes

0

extract-us-invoice.schema.json

{
  "type": "object",
  "required": [
    "vendor",
    "invoice_date",
    "total"
  ],
  "properties": {
    "total": {
      "type": "number"
    },
    "vendor": {
      "type": "string",
      "description": "Legal name of the vendor"
    },
    "currency": {
      "enum": [
        "USD"
      ],
      "type": "string"
    },
    "due_date": {
      "type": "string",
      "format": "date"
    },
    "subtotal": {
      "type": "number"
    },
    "sales_tax": {
      "type": "number",
      "description": "Sales tax amount, 0 if none"
    },
    "line_items": {
      "type": "array",
      "items": {
        "type": "object",
        "required": [
          "description",
          "amount"
        ],
        "properties": {
          "amount": {
            "type": "number"
          },
          "quantity": {
            "type": "number"
          },
          "unit_price": {
            "type": "number"
          },
          "description": {
            "type": "string"
          }
        }
      }
    },
    "invoice_date": {
      "type": "string",
      "format": "date",
      "description": "Issue date (YYYY-MM-DD)"
    },
    "invoice_number": {
      "type": "string"
    }
  }
}

Anthropic API (Python)

import json, anthropic

schema = json.load(open("extract-us-invoice.schema.json"))
client = anthropic.Anthropic()
resp = client.messages.create(model="claude-sonnet-5", max_tokens=1024,
    tools=[{"name": "extraire", "description": "Renvoie les données extraites", "input_schema": schema}],
    tool_choice={"type": "tool", "name": "extraire"},
    messages=[{"role": "user", "content": "your input here"}])
print(resp.content[0].input)

OpenAI format (response_format)

{
  "type": "json_schema",
  "json_schema": {
    "name": "extract-us-invoice",
    "schema": {
      "type": "object",
      "required": [
        "vendor",
        "invoice_date",
        "total"
      ],
      "properties": {
        "total": {
          "type": "number"
        },
        "vendor": {
          "type": "string",
          "description": "Legal name of the vendor"
        },
        "currency": {
          "enum": [
            "USD"
          ],
          "type": "string"
        },
        "due_date": {
          "type": "string",
          "format": "date"
        },
        "subtotal": {
          "type": "number"
        },
        "sales_tax": {
          "type": "number",
          "description": "Sales tax amount, 0 if none"
        },
        "line_items": {
          "type": "array",
          "items": {
            "type": "object",
            "required": [
              "description",
              "amount"
            ],
            "properties": {
              "amount": {
                "type": "number"
              },
              "quantity": {
                "type": "number"
              },
              "unit_price": {
                "type": "number"
              },
              "description": {
                "type": "string"
              }
            }
          }
        },
        "invoice_date": {
          "type": "string",
          "format": "date",
          "description": "Issue date (YYYY-MM-DD)"
        },
        "invoice_number": {
          "type": "string"
        }
      }
    },
    "strict": true
  }
}