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Agents · setup

One configuration block

Every MCP client wants the same three things: a command, its arguments, and stdio. Here they are for the clients people actually use, and the first prompt worth trying.

By , maintainer of AskISO and the ISO 20022 MCP servers. Last reviewed .

Before you start

Python 3.10 or later, and uv, which on macOS is installed with brew install uv. Once uv is present, uvx executes the gateway without installing anything permanently, which is the quickest way to establish whether the suite is worth adopting.

Claude Code

One command:

claude mcp add iso20022 -- uvx --from "iso20022-mcp[all]" iso20022-mcp

Claude Desktop

Add this to claude_desktop_config.json and restart:

{
  "mcpServers": {
    "iso20022": {
      "command": "uvx",
      "args": ["--from", "iso20022-mcp[all]", "iso20022-mcp"]
    }
  }
}

The tools appear beneath the tools icon after restarting, and Claude requests confirmation before each call, so every individual step remains approved by you.

Any other client

Command uvx, arguments --from "iso20022-mcp[all]" iso20022-mcp, transport stdio. That constitutes the entire contract, and it is everything any MCP client requires.

If you installed with pip install "iso20022-mcp[all]" rather than running it through uvx, the command is simply iso20022-mcp with no arguments.

Installing less than everything

The [all] extra installs every family. A more economical installation names only the families you actually require:

pip install "iso20022-mcp[pain,pacs]"

The gateway maintains a light core and loads families as extras, so an agent concerned only with initiating payments never carries the statement or securities machinery alongside it.

The first prompt

Begin with something you can verify by inspection:

Generate a pain.001 paying ACME Ltd 4,200 EUR from my account GB29NWBK60161331926819, then validate it.

The assistant identifies the appropriate message, generates it, and validates it against the schema before displaying anything. Where the IBAN is incorrect it says so, naming the rule responsible rather than merely the field.

A second prompt worth attempting, because it addresses the requirement most institutions actually have:

Check whether the addresses in this pacs.008 meet the CBPR+ structured address rule, and show me the compliant version.

What runs where

Everything executes on your own machine. The servers read the files you direct them towards and return their answers over stdio; there is no intermediary AskISO service and no account to create.

Schema validation requires the schemas themselves, which are not redistributed here. Download the message sets you need from iso20022.org, free of charge, and direct the tools at the folder containing them.

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