Aethelgard Ledger

What Aethelgard Ledger MCP server does

The Aethelgard Ledger MCP server provides accounting operations to MCP-compatible AI clients through a local executable. It manages companies, trusts, and individuals, with support for linking subsidiaries to a parent. Entities can operate across nine jurisdictions, according to the project documentation.

The ledger uses double-entry rules for every journal. A transaction is accepted only when its debit and credit totals balance; otherwise, the accounting engine rejects it and reports the reason. Accounts use standard categories: ASSET, LIABILITY, EQUITY, REVENUE, and EXPENSE.

Each entity's postings are connected through a SHA-256 hash chain. This makes changes made outside the ledger detectable when integrity is checked. The chain is unkeyed, so the latest hash should be recorded separately if it will be used for independent comparison.

How it works

The server runs locally and stores the ledger in a file on the user's machine. It does not send ledger data to Aethelgard Finance and does not include telemetry. Data returned by tools is still visible to the configured MCP client and the AI model, subject to those providers' terms.

A typical workflow is to create an entity, add its chart of accounts, and post balanced journals. The available read operations then expose entities, account lists, journal lines, and date-filtered transaction history. A trial balance reports balances for one entity.

The consolidate operation combines a parent with its direct subsidiaries by summing matching account codes. It is not a full consolidation process: intercompany eliminations are not performed by this MCP server and are handled in the Aethelgard desktop application.

Setup and configuration

Download a platform build from the project's Releases page. Builds are provided for Windows x86_64, macOS as a universal Intel and Apple Silicon package, and Linux x86_64 as a static archive. After extracting the executable, check it with aethelgard-mcp --version and register it as a local stdio server.

Claude Code can add the server with its MCP command. Claude Desktop, Cursor, and other clients can use an MCP configuration whose server entry supplies the executable path as the command. Windows configurations should point to aethelgard-mcp.exe and escape backslashes in JSON paths.

By default, files are stored in the platform-specific Aethelgard Ledger application-data directory. Set AETHELGARD_LEDGER_VAULT or pass --vault <DIR> to choose another location. The --ephemeral option creates a temporary ledger that is removed when the server stops. Use aethelgard-mcp --help for available options.

Tools and capabilities

The Aethelgard Ledger MCP server exposes these operations:

• create_entity: creates a company, trust, or individual and can assign a parent entity.
• create_account: adds an account under one of the five supported account types.
• post_transaction: records a double-entry journal and rejects unbalanced postings.
• list_entities: returns the entities in the ledger.
• list_accounts: returns an entity's chart of accounts.
• list_transactions: returns journal postings and their individual lines, with date filtering.
• trial_balance: returns a trial balance for one entity.
• consolidate: sums a parent's and its direct subsidiaries' balances by account code without intercompany eliminations.
• verify_integrity: checks the hash chain and returns the latest chain hash.

Limitations and notes

The software is closed source and distributed under the Aethelgard Ledger Evaluation Licence. That licence covers free evaluation and internal business pilots; production or commercial use requires a separate licence. The ledger file is not encrypted, and outputs should be independently verified before being relied upon. Third-party component licences are listed in the downloaded package.