Connect ChatGPT to Crane Ledger

Use Crane Ledger as the accounting system behind ChatGPT (custom connector / MCP). ChatGPT becomes the generative UI for your books.

Prerequisites

  1. A Crane Ledger account at craneledger.ai/auth/signin — GitHub, Google, Apple, or email magic link. New orgs start with 500 free credits.
  2. A ChatGPT plan that supports custom MCP connectors (typically Plus, Pro, Business, Enterprise, or Edu with developer features enabled).

ChatGPT MCP endpoint

SettingValue
URLhttps://api.craneledger.ai/mcp/chatgpt
TransportStreamable HTTP
Auth (OAuth)Sign in at consent UI — no key in the client. New accounts: craneledger.ai/auth/signin (500 free credits).
Auth (API key)Authorization: Bearer ha_live_…
Consenthttps://craneledger.ai/oauth/consent

This is the same MCP server as https://api.craneledger.ai/mcp, minus credit purchase and x402 top-up tools (purchase_credits, start_x402_credit_purchase, complete_x402_credit_purchase). Agent buyers and programmatic clients should keep using https://api.craneledger.ai/mcp, where those tools stay listed and callable.

Organization scope comes from your OAuth token or API key — you do not pass organization_id separately.

Scopes: ledger:read, ledger:write, and optionally ledger:admin.

See Authentication and MCP tools.

Connect via OAuth (recommended)

  1. In ChatGPT, add a custom connector / MCP server with URL:

    https://api.craneledger.ai/mcp/chatgpt

  2. ChatGPT discovers Crane Ledger’s OAuth authorization server and registers a client (DCR).

  3. You’ll be redirected to https://craneledger.ai/oauth/consent.

  4. Sign in if needed (GitHub, Google, Apple, or email magic link).

  5. Pick the organization and approve scopes (ledger:read, ledger:write, and optionally ledger:admin).

  6. Return to ChatGPT — enable the connector in the conversation if your client requires it.

Directory / plugin-library listings should use https://api.craneledger.ai/mcp/chatgpt. Product agents that need to buy or top up credits should use https://api.craneledger.ai/mcp.

Connect via API key

  1. In the Crane Ledger dashboard, create a live API key (ha_live_…).

  2. Configure the ChatGPT connector with:

    Authorization: Bearer ha_live_…

Use this for environments that do not support the OAuth consent UI.

Example prompts

Once connected, try:

  • "Set up a basic chart of accounts for a small service business"
  • "Create an invoice for $2,500 to Acme Corp for consulting"
  • "What's our cash position right now?"
  • "Show me profit and loss for last quarter"
  • "How many credits do I have left?"

Troubleshooting

IssueWhat to try
401 / auth failedRe-run OAuth consent, or confirm the Bearer key is live and not revoked
Wrong organizationRe-consent and select the correct org
Tools missingEnsure the connector is enabled for the current chat. Credit purchase tools are only on https://api.craneledger.ai/mcp
Insufficient creditsCheck Billing in the Crane Ledger dashboard, or connect the product MCP URL to purchase credits

Related

Need help?

Create a free account (GitHub, Google, Apple, or email) to access our support portal. Once signed in, use the Support tab in your dashboard to submit a support ticket — no GitHub account required. Our team typically responds within 24 hours.