camt053-mcp: An MCP Server for ISO 20022 Bank Statements

<p align="center"> <img src="https://cloudcdn.pro/camt053/v1/logos/camt053.svg" alt="camt053-mcp logo" width="128" /> </p>

A Model Context Protocol server that exposes the camt053 ISO 20022 Bank Statement library as tools for AI agents and assistants — discover message types and return reasons, inspect input schemas, validate records and financial identifiers, parse incoming statements, and generate validated reversing-entry XML, all from your favourite MCP client.

Latest release: v0.0.1 — nine MCP tools over stdio, all backed by the shared camt053.services layer, for Python 3.10+. See what's new →

Contents

• Overview
• Install
• Quick Start
• Tools
• Using the tools
• Development
• License
• Contributing
• Acknowledgements

Overview

The Model Context Protocol (MCP) is an open standard that lets AI agents and assistants discover and call external tools in a uniform way. camt053-mcp is an MCP server that turns the camt053 library into a set of first-class agent tools, so an assistant can read and reverse ISO 20022 camt.05x cash-management messages — the standardised bank-to-customer account reports, statements, and debit/credit notifications — directly from a conversation.

The headline capability is the one-shot reversing-entry workflow: read an incoming camt.053 statement, find the entries carrying a return reason code (e.g. AC04 Closed Account), and emit a validated reversing entry.

Every tool is a thin, typed wrapper over camt053.services — the single shared facade also used by the CLI and REST API — so all interfaces behave identically. Tools return JSON-serialisable data; on an error they return an {"error": ...} payload rather than raising.

• Website: https://camt053.com
• Source code: https://github.com/sebastienrousseau/camt053-mcp
• Bug reports: https://github.com/sebastienrousseau/camt053-mcp/issues

This package is part of the camt053 suite — a set of independently installable packages that share the camt053.services layer:

• camt053 — the core library (CLI + REST API)
• camt053-mcp — this package, the Model Context Protocol server
• camt053-lsp — the Language Server Protocol server for editors

flowchart LR
    A["MCP client<br/>(Claude Desktop, IDE, agent)"] -->|stdio| B["camt053-mcp"]
    B -->|delegates to| C["camt053.services"]
    C -->|parse + reverse + validate| D["ISO 20022 camt.053 XML"]

Install

camt053-mcp runs on macOS, Linux, and Windows and requires Python 3.10+ and pip. It pulls in the core camt053 library and the MCP SDK automatically.

python -m pip install camt053-mcp

Note: while the core camt053 library is not yet on PyPI, install it from source first:

python -m pip install "git+https://github.com/sebastienrousseau/camt053.git"
python -m pip install camt053-mcp

<details> <summary>Using an isolated virtual environment (recommended)</summary>

python -m venv venv
source venv/bin/activate        # macOS/Linux
venv\Scripts\activate           # Windows
python -m pip install -U camt053-mcp

</details>

Quick Start

Launch the server over stdio (the FastMCP default transport):

camt053-mcp

Register it with any MCP client (e.g. Claude Desktop) by adding it to the client's configuration:

{
  "mcpServers": {
    "camt053": { "command": "camt053-mcp" }
  }
}

The agent can then call the tools below to parse incoming statements and generate validated reversing entries on demand.

Tools

All tools delegate to the shared camt053.services layer, so they behave identically to the CLI and REST API.

Tool	Purpose
list_message_types	List the 3 supported camt.05x message types
list_return_reasons	List the ISO external return reason codes
get_required_fields	Required input fields for a message type
get_input_schema	Full input JSON Schema for a message type
validate_records	Validate flat records against a message type
validate_identifier	Validate an IBAN, BIC, or LEI
parse_statement	Parse an incoming camt.05x statement into data
filter_entries	Return entries carrying a return reason code
generate_reversal	Generate a validated reversing-entry XML document

Using the tools

You can invoke the tools in-process — without a transport — straight through the FastMCP instance. This mirrors what an agent receives over stdio. The runnable version of this snippet lives in examples/mcp_tools.py.

import asyncio

from camt053_mcp.server import server

# A complete camt.053 statement with one entry returned AC04 (Closed Account).
statement_xml = """<?xml version="1.0" encoding="UTF-8"?>
<Document xmlns="urn:iso:std:iso:20022:tech:xsd:camt.053.001.14">
  <BkToCstmrStmt>
    <GrpHdr><MsgId>STMT-MSG-0001</MsgId><CreDtTm>2026-06-15T08:00:00</CreDtTm></GrpHdr>
    <Stmt>
      <Id>STMT-0001</Id><CreDtTm>2026-06-15T08:00:00</CreDtTm>
      <Acct><Id><IBAN>GB29NWBK60161331926819</IBAN></Id><Ccy>EUR</Ccy></Acct>
      <Bal><Tp><CdOrPrtry><Cd>CLBD</Cd></CdOrPrtry></Tp>
        <Amt Ccy="EUR">10000.00</Amt><CdtDbtInd>CRDT</CdtDbtInd>
        <Dt><Dt>2026-06-15</Dt></Dt></Bal>
      <Ntry>
        <NtryRef>NTRY-0001</NtryRef>
        <Amt Ccy="EUR">1500.00</Amt><CdtDbtInd>CRDT</CdtDbtInd>
        <Sts><Cd>BOOK</Cd></Sts>
        <NtryDtls><TxDtls>
          <RtrInf><Rsn><Cd>AC04</Cd></Rsn></RtrInf>
        </TxDtls></NtryDtls>
      </Ntry>
    </Stmt>
  </BkToCstmrStmt>
</Document>"""


async def main() -> None:
    async def call(name, args):
        result = await server.call_tool(name, args)
        content = result[0] if isinstance(result, tuple) else result
        return content[0].text if content else ""

    # Validate an identifier.
    print(await call("validate_identifier",
                     {"kind": "bic", "value": "NWBKGB2LXXX"}))
    # -> {"kind": "bic", "value": "NWBKGB2LXXX", "valid": true}

    # Generate a validated reversing-entry document for the AC04 entries.
    xml = await call("generate_reversal",
                     {"xml": statement_xml, "reason_code": "AC04"})
    print(xml[:46])  # -> <?xml version="1.0" encoding="UTF-8"?> ...


asyncio.run(main())

Run it directly:

python examples/mcp_tools.py

Development

camt053-mcp uses Poetry and mise.

git clone https://github.com/sebastienrousseau/camt053-mcp.git && cd camt053-mcp
mise install
poetry install
poetry shell

This package depends on the core camt053 library. Until it is on PyPI, install it from source first: pip install "git+https://github.com/sebastienrousseau/camt053.git".

A Makefile orchestrates the quality gates (kept in lockstep with CI):

make check        # all gates (REQUIRED before commit)
make test         # pytest
make lint         # ruff + black
make type-check   # mypy --strict

License

Licensed under the Apache License, Version 2.0. Any contribution submitted for inclusion shall be licensed as above, without additional terms.

Contributing

Contributions are welcome — see the contributing instructions. Thanks to all contributors.

Acknowledgements

Built on the camt053 ISO 20022 Bank Statement library and the Model Context Protocol Python SDK.