
Zaxy
io.github.syndicaltPublished by GitHub account syndicaltv3.2.0Updated Oct 27, 2026
Event-sourced, auditable agent memory over MCP: cited checkout, replayable provenance.
Overview
Zaxy is a local, event-sourced memory server for AI agents, giving assistants an auditable project memory they can append to, query, replay and invalidate.
- What you can do
- Append and query memory: record missions, sessions, tool observations and cited findings, then retrieve them with hybrid exact, keyword, vector and graph search.
- Review and merge: keep parent and worker sessions isolated until findings are reviewed, conflicts checked and accepted results merged back.
- Replay and invalidate: inspect or replay the append-only history and mark facts invalid, with optional admin-token protection.
- Audit provenance: every accepted fact can be traced back to the immutable event log with hash-chained history and validity windows.
- Analyze model calls: an observe-only OpenAI-compatible packet analyzer records model-call provenance events.
- When to use it
- Useful when several agents or sessions work on one project and you want durable, citable memory instead of scattered markdown files or vector chunks. Best suited to teams that need to audit where an accepted fact came from and replay how project state evolved.
- Requirements
- Runs as a local stdio process installed from PyPI as zaxy-memory (for example with uvx or pipx) and needs Python. Setup is done with the zaxy init command, which creates a repo-local profile and stores data under a local .eventloom directory. The default embedded graph needs no external database; optional Neo4j and Pathlight extras require their own credentials.
Installation
In SourceWeft
- Open Zaxy in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.
Other MCP clients
Follow the launch instructions in the repository.
README
Zaxy
Production memory for agent teams that need receipts.
Zaxy turns agent context into an auditable project memory fabric. It captures parent missions, worker sessions, tool observations, cited findings, conflict review, approval packets, and accepted merge-back into one durable history that can be queried, replayed, and inspected.
Under the hood, Zaxy uses Eventloom append-only JSONL as the source of truth and an embedded LadybugDB graph projection for local reasoning. It is built for agents that need to remember what happened, cite where it came from, and avoid turning project state into a pile of markdown files and vector chunks.
The embedded LadybugDB graph projection is the default local runtime.
The plain install uses embedded LadybugDB. Install zaxy-memory[neo4j] only for the
optional Neo4j sidecar, and zaxy-memory[pathlight] only for Pathlight tracing.
Why It Matters
- Auditable memory: every accepted fact can point back to Eventloom history.
- Agent-team coordination: parent and worker sessions stay isolated until findings are reviewed and merged.
- Local-first runtime: the default path uses embedded LadybugDB, no Neo4j sidecar.
- MCP-native integration: Codex, Claude Code, Cursor, VS Code, Hermes Agent, LangGraph, CrewAI, and AutoGen can use the same memory interface.
Benchmark claims withdrawn (2026-07-03). The prior LongMemEval numbers were withdrawn: they were produced in oracle mode (mean ~1.9 candidate sessions per question, so Recall@5/citation-coverage were ~1.0 by construction, not by retrieval) and the preference-question scores rested on a hardcoded answer table that has since been removed. Zaxy does not currently publish a LongMemEval score. A real, full-haystack LongMemEval run is planned; until it lands, treat the earlier
0.956/0.910/1.000figures as retracted. The Harvey LAB claim is pending the same audit.
Quick Start
Install, init, verify
The PyPI distribution is zaxy-memory; the import package and console command
are still zaxy. Bare zaxy init sets up the local embedded graph posture,
repo-local profile, deterministic capture config, genesis event, heartbeat, and
MCP guidance. For Codex, the printed activation launcher starts the managed
capture watcher when the local capture config is present; pass --capture start
only when you want init itself to start the watcher before opening Codex. The
default human output is compact and action-first; add --verbose when you need
the full setup diagnostics, optional checks, fallback commands, resume guidance,
and notes.
For automation, zaxy init --json keeps the raw onboarding fields and adds
setup.status, setup.issues, setup.pending, readiness.status,
readiness.reasons, readiness.actions, and structured
readiness.action_items for both commands and non-command review tasks. Each
structured action carries label, command, original source, and hints
for compact-output tips such as activation <task> replacement and path-stable
command guidance. Installers can render those tips without parsing prose. It also
includes setup.summary, readiness.summary,
readiness.required_action_count, and readiness.reason_count, so client UIs
can render compact status without parsing human output. It also
separates readiness.blocking_diagnostics from
readiness.non_blocking_diagnostics so scripts can distinguish setup
completion, required actions, and advisory doctor warnings before relying on
live memory.
For Codex, zaxy init --codex-mcp-install auto is the default. It writes or
reuses the user-level Codex MCP config when that can be done without replacing
an existing zaxy server entry. If no safe config target exists, it prints the
copyable codex mcp add command. If an existing zaxy entry differs, it asks
you to review that config before replacing it because Codex can silently replace
servers with the same name. Use an explicit mode when you need to force one side
of that decision after review:
Both Codex paths keep the server workspace-neutral. After init, start or
restart Codex through the printed zaxy activate codex ... --launch command so
the MCP server list and Zaxy activation packet are loaded together. The printed
command includes explicit --eventloom-path and --workspace-root values, so
it still targets the initialized repo when copied from another shell.
Run the single-agent memory example:
Your local data lives under .eventloom/ as one append-only JSONL file per
session.
For Claude Code instead of Codex:
For Hermes Agent:
For repository development, use pip install -e ".[dev]", ./scripts/setup.sh,
and zaxy status. Start Docker sidecars only for integration tests or explicit
backend comparisons. Production setup writes Docker secret files under
./secrets/; see docs/deployment.md.
Architecture
Zaxy also includes an observe-only OpenAI-compatible packet analyzer for model
call provenance. It forwards packets to one configured upstream endpoint and
records llm.packet.completed events to Eventloom without acting as a router.
See LLM Packet Analyzer.
Public Site and Documentation
- Public static site:
site/index.html - Why Zaxy:
docs/why-zaxy.md - Getting started:
docs/getting-started.md - MCP quickstart:
docs/mcp-quickstart.md - Architecture:
docs/architecture.md - Configuration:
docs/configuration.md - MCP interface:
docs/mcp.md - Memory export contract:
docs/export-contract.md - Eventloom contract:
docs/eventloom.md - Graph schema:
docs/graph-schema.md - Retrieval:
docs/retrieval.md - Benchmarks:
docs/benchmarks.md - LLM packet analyzer:
docs/packet-analyzer.md - Embeddings:
docs/embeddings.md - Security:
docs/security.md - Operations and deployment:
docs/operations.md,docs/deployment.md,docs/runbook.md - Python API:
docs/api.md - Stability commitment:
docs/stability-commitment.md - Migration guide:
docs/migration.md - Archived benchmark iteration notes, release drafts, and research notes live
under
docs/archive/,docs/announcements/, anddocs/research/. - Contributing:
CONTRIBUTING.md
Key Features
- Immutable audit trail: Eventloom append-only JSONL with SHA-256 hash chains.
- Bi-temporal graph: Facts have validity windows (
valid_from,valid_to). - Hybrid extraction: Rule-based for typed events (60–80% cost reduction), LLM fallback.
- Hybrid retrieval: Exact + keyword + vector + graph traversal with configurable fusion weights.
- Session sharding: One Eventloom log per agent/session, with a shared graph.
- MCP-native: Drop-in memory for any MCP-compatible agent framework over stdio or SSE.
- Observable: Optional Pathlight traces, breakpoints, and diff support via
zaxy-memory[pathlight]. - Hardened local defaults: bounded MCP inputs, safe session IDs, no-sidecar embedded graph projection, and optional admin token support for replay/invalidation.
Project Structure
Production Secrets
Zaxy supports Docker/Kubernetes-style secret files for sensitive settings:
Direct environment variables take precedence over their *_FILE variants.
Use docker-compose.prod.yml as the production compose baseline.
Development
- Tests first (Karpathy rule). Every public function has a test.
- Unit tests mock external services. Integration tests use Docker for optional sidecar backends.
- Coverage gate: ≥92% enforced by CI.
- Lint/format:
ruff. Types:mypy.
The full suite must stay at or above 92% coverage before a sprint is complete.
Release Publishing
The PyPI distribution name is zaxy-memory because zaxy is already occupied
on PyPI. Published releases build from GitHub Actions and upload to
https://pypi.org/project/zaxy-memory/ using PyPI Trusted Publishing with
GitHub OIDC. The import package and console command remain zaxy.
Before publishing, run zaxy doctor --release-smoke to verify the package
version, changelog entry, release workflow, tokenless publishing posture, and
dependency-light LangGraph example.
License
MIT
Source: README.md at commit 892b108
Tools
0Version history
1- v3.2.0LatestSep 16, 2026
Score
50% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
- Reached in the last 30 days25 pts
Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.
- Auth declared10 pts
Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.
- Tools listed15 pts
Answer tools/list without a credential, or ship a package that starts in a sandbox without one.
- DescriptionRequired15 pts
- Logo10 pts
- Documentation15 pts
- License10 pts