canonical: https://jentic.com/apis/pennylane.com/pennylane

# Pennylane API

Jentic publishes the only available OpenAPI specification for Pennylane API, keeping it validated and agent-ready. Pennylane API provides programmatic access to accounting operations for French businesses, including journal entry management, ledger account creation, and webhook subscriptions. The API uses OAuth 2.0 with authorization code flow and exposes 10 endpoints focused on core bookkeeping operations for syncing financial data between Pennylane and external systems.

## For AI agents

Create and retrieve journal entries and ledger accounts for French business accounting. Manage webhook subscriptions for real-time accounting event notifications.

## Scope

Does not handle invoicing, expense management, or tax filing - use for journal entries, ledger accounts, and accounting event webhooks only.

## Capabilities

- Create and retrieve journal entries with line-item detail for double-entry bookkeeping
- Define and query ledger accounts within the French accounting plan structure
- Subscribe to accounting event webhooks for real-time change notifications
- Synchronize financial records between Pennylane and external ERP or invoicing tools
- Retrieve individual journal entries and ledger accounts by identifier

## Use cases

### Automated Journal Entry Creation

Automate the creation of journal entries from external transaction sources such as payment processors, bank feeds, or e-commerce platforms. The Pennylane API accepts structured journal entry data via POST /journals with line items, dates, and account codes. Agents can transform incoming transaction data into compliant French double-entry bookkeeping records without manual data entry.

Example prompt: Create a journal entry via POST /journals with two line items (debit and credit) for a 500 EUR client payment, specifying the appropriate ledger account codes

### Chart of Accounts Management

Programmatically manage the chart of accounts by creating new ledger accounts and querying existing ones. The API provides POST /ledger_accounts for creation and GET /ledger_accounts for listing. This enables synchronization of the account structure between Pennylane and other financial systems or ERP tools used by French businesses.

Example prompt: Create a new ledger account via POST /ledger_accounts with account code 411001, label 'Client XYZ', and the appropriate account type

### Real-Time Accounting Event Webhooks

Subscribe to Pennylane webhooks to receive notifications when accounting events occur, such as new journal entries being validated or ledger accounts being modified. The webhook subscription endpoint (POST /webhook_subscription) enables event-driven architectures that keep downstream systems synchronized without polling.

Example prompt: Create a webhook subscription via POST /webhook_subscription with a callback URL to receive notifications for journal entry creation events

### AI Agent Accounting Operations via Jentic

AI agents discover and execute Pennylane accounting operations through Jentic without building a custom OAuth integration. Agents search for accounting capabilities by intent, receive operation schemas with OAuth token handling managed by Jentic, and create journal entries or manage accounts through a unified interface. This reduces integration from days to under an hour.

Example prompt: Search Jentic for 'create a journal entry', load the POST /journals operation schema with OAuth scopes resolved, and execute with structured line-item data

## Key endpoints

| Method | Path | Description |
| --- | --- | --- |
| GET | `/journals` | List journal entries |
| POST | `/journals` | Create a journal entry |
| GET | `/journals/{id}` | Get a specific journal entry |
| GET | `/ledger_accounts` | List ledger accounts |
| POST | `/ledger_accounts` | Create a ledger account |
| POST | `/webhook_subscription` | Create a webhook subscription |

## Key resources

- **Journals** — Create and retrieve journal entries for double-entry bookkeeping
- **Ledger Accounts** — Define and query accounts in the chart of accounts
- **Webhook Subscription** — Manage webhook subscriptions for accounting events

## AI readiness

This API is usable in Jentic One now. Its AI-readiness score against Jentic's framework shows where it stands today and where improvements would make it even easier for agents to use.

- **Score:** 74 / 100
- **Maturity:** AI-Aware
- **Dimensions:**
  - Foundational Compliance: 100 / 100
  - Developer Experience & Jentic Compatibility: 63 / 100
  - AI-Readiness & Agent Experience: 53 / 100
  - Agent Usability: 94 / 100
  - Security: 90 / 100
  - AI Discoverability: 100 / 100
- **View full report:** https://jentic.com/apis/pennylane.com/pennylane/scorecard
- **How the score is calculated:** https://docs.jentic.com/reference/api-readiness-framework/overview/
- **More about the dimensions:** https://docs.jentic.com/reference/api-readiness-framework/specification/#dimensional-model-overview

### Score it yourself

Every API in the directory is allowlisted, so you can re-score it with no key required.

- **Score your own API:** https://jentic.com/scorecard.md
- **Scoring CLI agent skill:** https://github.com/jentic/jentic-api-scorecard/blob/main/skills/jentic-api-scorecard/SKILL.md

```sh
npx @jentic/api-scorecard-cli score <openapi-url>
```

## Why Jentic

- **Setup:** Wiring Pennylane by hand means running its OAuth 2.0 authorization code flow against app.pennylane.com, storing and refreshing tokens, and threading journal and ledger ids through your calls yourself. Through Jentic you install once, import the Pennylane API from the API Directory, complete the OAuth grant once, and your agent calls it while token refresh is handled for you.
- **Permission scoping:** Pennylane puts the journal id in the URL path (`/journals/{id}`), so a rule can pin your agent to reading a specific journal. You choose the operations it may call, so creating journal entries or ledger accounts and subscribing a webhook are included only if you add them.
- **Credential handling:** Your Pennylane OAuth token is stored once, encrypted, by your own Jentic One instance and injected at execution time, with refresh handled automatically. It never enters the agent's prompt, logs, or context.
- **Discovery method:** Agents search Jentic by intent such as 'create a journal entry', and Jentic returns the matching Pennylane operation with its input schema and resolved OAuth scopes so the agent calls the right endpoint without browsing the reference docs.

## Related APIs

- **Xero Accounting API** — Xero provides broader accounting coverage with invoicing, bank reconciliation, and multi-currency support for global businesses.
- **Sage API** — Sage offers enterprise accounting with French localization and broader ERP capabilities.
- **Gusto API** — Gusto handles payroll processing that generates journal entries consumable by Pennylane.

## FAQ

### Why is there no official OpenAPI spec for Pennylane API?

Pennylane does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Pennylane API via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer.

### What authentication does the Pennylane API use?

The Pennylane API uses OAuth 2.0 with the authorization code flow. The authorization URL is https://app.pennylane.com/oauth/authorize and the token URL is https://app.pennylane.com/oauth/token. Through Jentic, OAuth token acquisition and refresh are handled automatically so agents do not manage the flow directly.

### Can I create journal entries with multiple line items?

Yes. POST /journals accepts a structured payload with multiple line items, each specifying an account code, amount, and debit/credit direction. This supports standard double-entry bookkeeping where debits equal credits within each journal entry.

### How do I manage webhook subscriptions through Jentic?

Search Jentic for 'subscribe to accounting events' to discover the POST /webhook_subscription operation. Load the schema and execute with your callback URL. The API also supports GET /webhook_subscription to check current configuration, PUT to update, and DELETE to remove subscriptions.

### What are the rate limits for the Pennylane API?

The OpenAPI specification does not document specific rate limits. Implement standard retry logic with exponential backoff on HTTP 429 responses. The API is designed for integration use cases rather than high-frequency bulk operations.

### Can I list and filter journal entries by date range?

GET /journals returns journal entries with support for query parameters. The endpoint enables retrieval of entries for reconciliation, reporting, or audit purposes. Individual entries can be fetched by ID via GET `/journals/{id}.`

### Can I limit what my agent is allowed to do with the Pennylane API?

Yes. Because Jentic One is self-hosted, your own rules decide which Pennylane operations and credentials the agent may use, so it can read journal entries and ledger accounts without being able to create them or subscribe a webhook unless you add those operations. Since Pennylane puts the journal id in the URL path at GET `/journals/{id}`, a rule can pin the agent to a specific journal rather than the whole account. The stored OAuth token is injected only for the calls you allow, so writes like POST /journals, POST /ledger_accounts, and POST /webhook_subscription happen only when you have explicitly granted them.