Agentvcs

Versioning evolving agents with agentvcs

agentvcs is a multidimensional VCS: each commit captures code + goal + models + trace and a state (fluid = evolving, crystallized = frozen/deterministic). Use it to make your own iterative work inspectable, reversible, and freezable.

Always pass --json

Run every command with --json. Output is one JSON object: {"ok": true, ...} on success, {"ok": false, "error": {"code": "...", "message": "..."}} on failure. Branch on the code, never on the message. Codes: NOT_A_REPO, ALREADY_REPO, NO_COMMITS, NO_PARENT, BAD_REF, AMBIGUOUS_REF, BRANCH_EXISTS, ALREADY_CRYSTALLIZED.

If your shell cwd is not sticky, use -C

Pass -C <project-dir> (like git -C) to run against that repo from anywhere: agentvcs -C /path/to/proj commit -m "..." --json. init creates the dir if absent.

The non-code state lives in agent.json

{ "goal": "...", "models": [{"provider":"...","model":"...","params":{...}}],
  "trace": "traces/run.jsonl", "state": "fluid", "metrics": {} }

Keep goal current. The trace is the message history you are versioning beyond code; you can supply it two ways:

• Path (manual): "trace": "traces/run.jsonl" — append agent messages as you work.
• Provider (automatic, preferred in Claude Code):

  "trace": { "provider": "claude-code", "auto": true },
  "models": [{ "provider": "anthropic", "auto": true }]
  

  You then maintain no trace file: commit auto-vacuums Claude Code's native session transcript (real tool_use/tool_result/thinking), and the model pin is detected from what actually ran. Add "redact": ["sk-[A-Za-z0-9-]+", ...] to scrub secrets, or "session" / "project_dir" to pin a specific transcript.

Core loop

agentvcs init --json                      # if no .agentvcs/ yet (scaffolds agent.json + AGENTS.md)
# ... edit code, update agent.json's goal, append to the trace file ...
agentvcs commit -m "what changed" --json  # after each meaningful iteration
agentvcs status --json                    # uncommitted changes, per dimension
agentvcs diff --json                      # parent..HEAD: which dimension moved?

When you break something

agentvcs rollback --json                  # restore full prior state (HEAD's parent)
agentvcs rollback <ref> --json            # ...or to a specific commit (short prefix ok)

Rollback is reversible: the prior head is reported as previous_head and saved to .agentvcs/ROLLBACK_HEAD. Recover with agentvcs checkout <previous_head>.

Explore alternatives safely

agentvcs branch try-b --json && agentvcs checkout try-b --json
# evolve a different strategy here; keep the winner

When a solution is trusted, freeze it

agentvcs freeze --json                    # crystallize HEAD -> deterministic recipe

This pins every model to temperature 0 and writes a replayable recipe to crystal/<commit>.json. Re-running a crystallized commit is reproducible and cheap. A crystallized commit cannot be re-crystallized (ALREADY_CRYSTALLIZED).

Re-execute a frozen recipe deterministically:

agentvcs replay --json                    # emit the frozen goal/models/steps
agentvcs replay --exec "my-runner" --json # pipe each step (JSON) to your executor

Replaying a fluid commit errors with NOT_CRYSTALLIZED — freeze it first.

Inspect the captured conversation

agentvcs trace --json                     # which session/file is hooked (+ message count, model)
agentvcs show --trace --json              # the commit + the full conversation that produced it

Show a human the evolution (local dashboard)

agentvcs ui --json                        # serve http://127.0.0.1:8080; prints {url,host,port}
agentvcs ui --no-open --json              # headless (no browser); keeps serving until stopped

A read-only split view: commit graph on the left; per commit, its dimensional diff plus the trace rendered as a chat (thinking/tool_use/tool_result). Polls, so commits appear live. Read-only, loopback-only, zero dependencies.

Run it continuously inside Claude Code

Wire it once and the frame is always-on, no per-turn work:

agentvcs init --claude-code --runtime     # in the dir you launch Claude Code from

// ~/.claude/settings.json — live budget/$/context in the status bar, every render
"statusLine": { "type": "command", "command": "agentvcs statusline" }
// .claude/settings.json — auto-commit the frame each turn (a versioned session)
"hooks": { "Stop": [ { "hooks": [
  { "type": "command", "command": "agentvcs commit -m 'cc checkpoint'" } ] } ] }

The statusLine command must run where the runtime repo lives (cwd-based, or pass -C <repo>); statusline drains and ignores the session JSON Claude Code pipes it, so it can't hang the bar. agentvcs log then reads as the session's frame history.

MCP alternative

If the agentvcs MCP server is connected, the same operations are available as tools avcs_log, avcs_show (pass trace:true for the conversation), avcs_trace, avcs_diff, avcs_status, avcs_commit, avcs_freeze, avcs_replay, avcs_rollback, avcs_branch, avcs_checkout, avcs_merge, avcs_eval, avcs_recall, avcs_runtime, avcs_budget, avcs_context. Each returns the same {"ok": ...} JSON. Register with: claude mcp add agentvcs -- agentvcs-mcp.