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Vanni Daghini
Vanni Daghini

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Declarative and observable monitor management with Python

tool-clean: a declarative and observable approach to monitor management

When dealing with system configuration, I tend to prefer explicit control over automation.

This is especially true in IT environments, where:

  • predictability matters more than convenience
  • implicit behavior becomes technical debt
  • “magic” often hides responsibility rather than reducing it

With that mindset, I built tool-clean.


What tool-clean is (and is not)

tool-clean is a CLI tool written in Python for observable and declarative monitor management.

It allows you to:

  • observe connected monitors
  • identify them in a stable way
  • assign human-readable labels
  • declare usage profiles
  • associate profiles to monitors
  • persist everything locally
  • audit all mutating actions

What it does not do:

  • it does not apply system configurations
  • it does not change brightness or resolution
  • it does not interact with drivers or OS APIs
  • it does not make autonomous decisions

This is intentional.


The design philosophy

tool-clean is built around a few non-negotiable principles:

  • Human control is explicit
  • Observation is separate from intention
  • Declaration is separate from execution
  • Nothing happens implicitly
  • Everything relevant is audit-visible

In practice, this means the tool never “reacts” to state.

It only records and exposes it.


Why not automate?

Automation is powerful, but it comes with costs:

  • hidden assumptions
  • unclear responsibility
  • difficult audits
  • fragile edge cases

In many IT contexts, the real need is not automation, but clarity.

tool-clean is meant to be a foundation:

  • something an IT operator can reason about
  • something you can inspect and revoke
  • something that does not surprise you six months later

How it works (conceptually)

  1. The system observes the real state (connected monitors)
  2. The user declares a profile (an intention, not an action)
  3. The user associates that profile to a monitor
  4. The state is persisted and audited
  5. Any real application happens outside the tool

The tool remains read-only with respect to the operating system.


Technical overview

  • Python 3.10+
  • CLI-first (not a library)
  • Local-only execution
  • SQLite for persistence
  • Append-only audit log (INFO / WARN / SECURITY)
  • No network dependencies
  • No background services

The project uses a clean src/ layout and a strict separation between:

  • CLI parsing
  • domain commands
  • observed state
  • persistence

Current scope: Base v2

The current public release is Base v2.

It is intentionally limited:

  • no centralized management
  • no federation
  • no policy enforcement
  • no automatic configuration application

Those ideas may belong to future versions, but not to the base.

Base v2 is meant to be:

  • stable
  • inspectable
  • defensible

Repository

The project is open source (MIT licensed):

https://github.com/Vanni7544/tool-clean

The repository includes:

  • full documentation
  • a canonical source snapshot
  • clear contribution guidelines
  • a defined security policy

Closing thoughts

tool-clean is not meant to be flashy.

It is meant to be:

  • boring in the right way
  • predictable
  • explicit
  • safe to reason about

If you’re interested in tools that favor clarity over automation,

this project might resonate with you.

Technical feedback is welcome.

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