Aglium Ledger client

Your coding agent sees your repository. Ledger sees what your changes might affect elsewhere.

Claude Code can work on the repository in front of it. The change often reaches further: another team's branch on the same ticket, a service that reads the table you are changing, a design decision whose open question this change quietly answers. Ledger reads the rest of your organisation's repositories on your own machine and answers, for a branch: a recommendation, the evidence behind it, and the people or decisions to involve.

Source-available · No Aglium account · No model calls by the client · Nothing sent to Aglium

Would it have warned you? Replay your last merges

The quickest way to find out whether Ledger is useful to you is to run it on changes your team already merged, as they were on the day each one started.

In Claude Code:

/plugin marketplace add Aglium/ledger-client
/plugin install ledger@aglium
/ledger:setup       # writes a config, checks prerequisites, says which repositories Ledger can see
/ledger:replay      # your merged changes from the last 90 days; --everyone for your team's

From a terminal (Python 3.12+ and uv):

uv tool install 'aglium-ledger[mcp]'
cd ~/src/your-org/one-of-your-repos
aglium-ledger init          # a config from this checkout; contacts nothing
aglium-ledger mirrors       # optional: the rest of the organisation, as bare mirrors
aglium-ledger coverage      # which repositories Ledger can see, and the gaps
aglium-ledger replay --everyone

The replay writes ledger-replay.md. For each change it keeps three outcomes apart:

• something to say: other work or contracts this change affected, each with links to the commits and files you can open to check it, and how strong the claim is (a conflict: it removes something another repository reads, or cannot land with another change in flight; a dependency: it faces another repository over a named topic or route; or a correlation, such as a shared ticket);
• nothing found, by a replay that could see enough to say so;
• could not see enough to tell, which is never the same as safe.

There is no hindsight in it: every other repository is read at the commit its default branch had on the day the change started, so nothing merged later can make a finding look smarter than it was. More in docs/replay.md.

You then say, for each finding, whether it was useful, already known, a false positive, or something you can't verify. The answers stay on your machine (aglium-ledger feedback import ledger-replay.md). If you want to share the result, aglium-ledger feedback summary --share writes a file with the verdicts and hashed names, no code, for you to read and send.

The recommendation

aglium-ledger brief <repo> <branch> gives it for any branch; --json for a CI gate or an agent. Every answer names the repositories it read, so a quiet answer from a small estate is not mistaken for a clean one.

Commands

Use it from a coding agent

• Claude Code: the plugin in plugin/ adds the skill, the MCP server, a push-time hook and /ledger:setup, /ledger:coverage, /ledger:brief, /ledger:replay.
• Any MCP client: run aglium-ledger mcp as a stdio server. Tools: brief, who_owns, inflight_for, decisions_for, feedback.

Installation on a clean machine, permissions and troubleshooting: docs/install.md.

On a pull request

The GitHub Action in this repository runs the client statelessly on each pull request and comments with the full brief: a field or contract the change removes that another repository reads, another change in flight that cannot land with it, who is on the other side of each topic or route, and other work linked by ticket, by what it touches or by author. A branch with no ticket key is briefed like any other. It is advisory and never fails a build; set mode: siblings for the old ticket-only comment.

- uses: Aglium/ledger-client@v0.1.1
  continue-on-error: true
  with:
    github-token: ${{ secrets.LEDGER_TOKEN }}
    config: .github/ledger.yml

Trust and data

The client runs on your machine. It reads your repositories with the credential git already has, sends nothing to Aglium, makes no model calls, and puts no file contents in its answers: they carry names, contracts, decisions and paths. Exactly what it reads, contacts and stores is in docs/trust.md.

Client and server

The client is complete by itself and free to use. It reads the estate live, on demand, from what is on your machine. What it does not do, alone:

• see repositories or branches that are not on this machine;
• answer in about 2 seconds (it reads again each time: seconds to tens of seconds);
• read topic wiring declared in infrastructure (ACLs, Terraform, AsyncAPI), only code and config;
• check every field of a contract (it checks the names a change removes, in consumers' code);
• see work merged to an integration branch and not released, or decisions on unmerged branches;
• say anything before code exists, or notice documentation a change leaves wrong;
• share findings and feedback with your team, or learn which verdicts were right.

An organisation server does all of these, for everyone, through the same plugin and commands. Side by side: docs/client-vs-server.md. aglium-ledger server says the same from the command line.

Licence

PolyForm Shield License 1.0.0: source-available, not open source. Free to use, change and redistribute, at work too; not to build a product that competes with Ledger. The licence text is what counts. Copyright (c) 2026 Aglium, aglium.com.