SynartesisReadonly
A lookup, a search, a list. Nothing changes.
Recorded and forwarded.An undo layer for AI agents
Let agents act.
Let agents act.
Keep a
way back.
Synartesis records what your agent changes, keeps the state it replaced, and asks you first when there’s no way back.
npm install -g synartesis
Node.js 22+Install & connect your agent ↗
A change, with its way back
report.txt
− North 412,800
+ North 0
South 288,400
Prior state captured
This change can be put back.
Restore North to 412,800. South stays as it is.
In a real run, the plan checks for later changes before it writes.
Interactive example
Nothing runs on your disk
Nothing runs on your disk
Between intent
and consequence
and consequence
Four ways inChoose your
Choose your
path.
The same journal and the same undo underneath all four. Start wherever you already work.
01 / Cover what you have
The clients on this machine
One command, every client.
Finds what Claude Code, Claude Desktop, Cursor and Codex already list and points every entry at the proxy. Your config is copied aside first.
synartesis install
02 / The screenEverything on the arrow keys
One screen, no flags to remember.
What your agents have done, what is held for approval, every AI on the machine, and the undo for any of it.
synartesis
03 / The desktop windowThe same engine, with a conversation
Any model, including one on your own machine.
Every tool the model calls goes out through the proxy on its way, so the undo is not a feature the window implements.
synartesis desktop
04 / Your own serverA policy for anything else
Four ship with a policy. Hundreds do not.
Introspect a server, draft a manifest from what it says it can do, then correct it where you know better. Undeclared tools stay held.
synartesis init crm -- ./crm-mcp
01 / The order mattersBefore the write.
Before the write.
A way back.
First, keep the value that is there. Then let the agent change it. When you undo, that captured value is what comes back.
01 / Capture
Keep North: 412,800.
02 / Change
The agent writes North: 0.
03 / Put back
Restore North: 412,800.
Watch the evidence: twenty real calls against a toy CRM
02 / The desktop window
A conversation.
A conversation.
A visible way back.
Talk to a model. See every tool call, what it changed, and whether it can be put back. The window and the CLI share the same journal and undo engine.
Download the desktop app
The tool card shows “Prior state captured”. The ledger counts one change, with one that can be put back.
Open full-size ↗
Your model. Including a local one.
Claude, Gemini, Mistral, OpenAI, or a compatible /v1/chat/completions endpoint. Run models locally with Ollama or LM Studio, without paid API calls or sending prompts to a model provider.
macOS · Apple silicon & Intel
Windows · Linux
After installing the desktop app, open it with synartesis desktop on any platform.
The builds are unsigned. macOS Gatekeeper and Windows SmartScreen will block or warn on first launch. Read before installing ↗
What is checked before one is built. Every installer is produced by a workflow that first runs the whole gate — build, typecheck, lint and the entire test suite — on the tagged commit, so a binary cannot be attached to a release from code that fails its own suite. The tests run on Linux and macOS across Node 22 and 24. The Windows installer is built and not tested; nothing in CI exercises it, which is worth knowing before you install it.
03 / The contract
Know what can
Know what can
come back.
You define what each tool does and how to take it back. Synartesis enforces that policy. An unknown tool is treated as irreversible, so it waits for a person.
Four kinds of call. Four different ways through.
Reversible
The state before the write is captured and kept.
Prior state restored on undo.Compensable
A second action offsets the first. It is not an exact rewind.
Offset on undo.Irreversible
An email sent. A message seen. No honest inverse.
Held for human approval.Read the four safeguards, in order
-
Classify. Ask if it cannot be undone.
Match the tool against your policy. Calls that need approval stop before they reach the system.
-
Capture before changing anything.
Read what is about to be overwritten. If capture fails, the write does not silently go through.
-
Journal, then forward.
Record the call before sending it. Store its reversing call while the old value is still available.
-
Check again before putting it back.
Undo walks newest first and checks for later changes. It stops at a conflict, with the steps already restored left in place.
The refusal is part of the promise
Someone changed it
Someone changed it
since? Stop.
Undo re-reads the resource and compares it with the state your run left behind. If somebody has been there since, Synartesis shows the difference and stops on that step.
Resolve the conflict, then undo --replan can continue. Work already put back stays put back.
$ synartesis undo halt crm.update_customer the resource has changed since this run. − churn risk + spoke to her Tuesday 1 removed, 1 added.
RESULT · partial — stopped at the conflict
04 / Under the window
The terminal
The terminal
is still home.
Run synartesis for the interactive journal. Or use the commands directly, from wherever you work.
synartesis install
Connect the clients already on your machine. Their configs are backed up first.
synartesis status
See which clients are covered, and when calls last came through.
synartesis show --live
Check touched resources against their recorded state, without writing.
synartesis undo
Walk the run backwards, stopping where it cannot safely continue.
Honest limits
Where protection
A policy saying
Where protection
ends.
Only calls through the proxy
Direct HTTP calls, shell commands, and browser actions outside MCP are invisible to Synartesis. If your agent bypasses the proxy, those changes are not recorded.
Some actions cannot be undone
It cannot un-send an email or undo more than the system underneath allows. Those calls need human approval. A compensating action offsets a change; it does not erase history.
Captures have limits
A resource too large to capture, or one that cannot be read, cannot silently be treated as recoverable. The write is refused or held for approval with the reason shown.
Undo is not all-or-nothing
It walks newest first. If it stops at a conflict, changes already restored stay restored. A call still marked pending has an unknown outcome; the journal does not pretend otherwise.
Three of the four bundled policies are round-tripped. One is not.
filesystem and memory are round-tripped against the real server in the test suite: the change is made, undone, and the result compared — byte-for-byte restoration for files, and for the knowledge graph, what the agent added gone and what was already there untouched. git is round-tripped for the one thing it can do: that server exposes no tool that restores content, so the policy holds a single compensation, and the test proves staging comes back off the index with the working tree untouched, a commit is held, and a branch switch goes through and is reported as something undo cannot take back. It also pins the overreach — this server's reset unstages everything, so undoing the agent's staging unstages a person's too, which is why it is recorded as a compensation and not an undo. github is not tested at all: its tools are checked to exist and nothing has run an undo through them, so treat it as untested and do not rely on it for anything you cannot afford to lose.
A policy saying live is not a promise that undo works
It says the policy has met its server and the tools take the arguments it passes them. Whether it puts anything back is a separate question that only a test against the real server answers. synartesis check says so under the server list rather than letting one word stand for both.
The journal needs looking after
The prior state is what makes undo possible, so the local SQLite journal grows. Pruning old runs removes their recovery data too. Keep it for as long as you need a way back.
ΣΥΝΑΡΤΗΣΙΣ · A fastening together
Keep hold of
Keep hold of
the other end.
An agent acts. Synartesis keeps the record.
It is a young project, and a star is most of how anybody finds out it exists. Star it on GitHub ↗
npm install -g synartesis