Available

REST API + AccountsOS

Full accounting API for custom integrations

Direct HTTP access to all 13 AccountsOS tools. Bearer token authentication, JSON request and response format, and comprehensive documentation. Build custom integrations, dashboards, or agent workflows.

Endpoints

Scopes

JSON

Format

99.9%

Uptime

Get Started View API Docs

API request example

curl -X POST https://accounts-os.com/api/mcp \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "type": "tool",
    "name": "get_transactions",
    "arguments": {
      "from_date": "2026-01-01",
      "to_date": "2026-01-31",
      "direction": "out",
      "limit": 50
    }
  }'

Available Tools

Tool	Description	Scope
`get_transactions`	Query income and expenses with date and direction filters	read
`get_balance`	Check current account balances across all accounts	read
`get_vat_summary`	Get VAT position for any quarter	read
`get_deadlines`	List upcoming filing deadlines	read
`create_transaction`	Record income or expense entries	write
`update_transaction`	Modify transaction details or categories	write
`categorize_transaction`	Get AI category suggestion for a transaction	write
`list_categories`	Browse HMRC-aligned expense and income categories	read
`create_deadline`	Add custom filing deadlines and reminders	write
`search_documents`	Find receipts, invoices, and contracts	read
`upload_document`	Store receipts and invoices with metadata	write
`get_dla_balance`	Check Director's Loan Account with S455 warnings	read
`get_invoices`	List and filter invoices by status	read

Features

13 endpoints covering transactions, VAT, deadlines, documents, and invoices

Bearer token authentication with scoped API keys

JSON request and response format throughout

AI-powered transaction categorisation endpoint

Webhook support for real-time event notifications

Rate limiting with generous free tier

How It Works

Get your API key

export ACCOUNTSOS_API_KEY="sk_live_..."

Make your first request

All requests go to /api/mcp with a JSON body specifying the tool and arguments.

curl -X POST https://accounts-os.com/api/mcp \
  -H "Authorization: Bearer $ACCOUNTSOS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"type":"tool","name":"get_balance","arguments":{}}'

Build your integration

Use any HTTP client in any language. Build dashboards, automate workflows, or power AI agents.

# Python, JavaScript, Go, Rust — any language
import requests
result = requests.post(API_URL, headers=headers, json={
  "type": "tool",
  "name": "get_transactions",
  "arguments": {"limit": 10}
}).json()

Benefits

Works with any programming language or HTTP client

Build custom dashboards, reports, and automations

Integrate accounting into existing agent workflows

Scoped API keys with read, write, and admin levels

Comprehensive error handling and rate limiting

Frequently Asked Questions

What authentication method does the API use?

Bearer token authentication. Include your API key in the Authorization header as 'Bearer sk_live_...'. API keys are scoped to read, write, or admin permissions.

What is the API request format?

All requests are POST to /api/mcp with a JSON body containing 'type' (tool or resource), 'name' (the tool name), and 'arguments' (tool-specific parameters). Responses are JSON.

Are there rate limits?

Yes. The free tier allows 100 requests per minute. Paid plans have higher limits. Rate limit headers are included in every response so you can track usage.

Can I use the API for automated workflows?

Absolutely. The API is designed for automation. Use it in cron jobs, CI/CD pipelines, serverless functions, or any scheduled workflow. Common use cases include daily expense imports, weekly finance summaries, and quarterly VAT preparation.

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