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achlens

PyPI

A local-first ACH file validation foundation.

Versions collected1

Direct dependencies3From release 0.1.2

Last observed20 Oct, 18:12 UTC

README

Version 0.1.2 documentation

achlens

achlens is a local-first Python MCP server and CLI for inspecting synthetic ACH files. It parses fixed-width records, validates structure and control totals, explains findings, masks sensitive fields, repairs derived controls, and generates deterministic test files. It never transmits ACH files or makes bank/network calls.

Use synthetic data only. This project is not a bank gateway, compliance advisor, or transmission system.

Quick Start

uv sync
uv run achlens --help
uv run achlens validate tests/fixtures/golden/sample_valid.ach
uv run achlens generate --sec PPD --entries 5 --seed 7 > synthetic.ach

In Windows PowerShell, use an explicit ASCII encoding because PowerShell's default > redirection can write UTF-16 output that is not valid ACH text:

uvx achlens generate --sec PPD --entries 5 --seed 7 |
	Set-Content -Encoding ascii synthetic.ach

Run the MCP server over stdio:

uv run achlens serve

The MCP server exposes validation, summaries, parsed-record paging, control explanations, routing checks, code lookup, synthetic generation, and control repair. See docs/tools.md for the current tool surface.

Sensitive fields are masked by default. Configure ACHLENS_ALLOWED_ROOTS to enable MCP path inputs; otherwise provide file content directly. See SECURITY.md for the data and write boundaries.

Development

This project uses uv.

uv sync
uv run achlens --help
uv run pytest -q
uv run ruff check .
uv run ruff format --check .
uv run mypy --strict src

Never add real payment data, account numbers, or ACH files to this repository.

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Versions 1

Collected releases

Version	Published	Direct dependencies	Open version
0.1.2	12 Sept 2026	3

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Observed since 20 Oct, 18:12 UTC

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package:c6c762823b98b0c6424e74643162443cb7e215aee311f15cdce4e059e4ad54d9

Package details

Ecosystem: PyPI
Registry license: Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. Definitions. "License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. "Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. "Legal Entity" shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity. "You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License. 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You are solely responsible for determining the appropriateness of using or redistributing the Work and assume any risks associated with Your exercise of permissions under this License. 8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages. 9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability. END OF TERMS AND CONDITIONS Copyright 2026 achlens contributors
Collected versions: 1
Source: PyPI

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pkg:pypi/achlens

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Source & dates

Source modified: Unknown
First observed: 20 Oct 2026
Last observed: 20 Oct, 18:12 UTC

Publication, source changes and collection are separate events.