Cortex Engine

@fozikio/cortex-engine

[](https://www.npmjs.com/package/@fozikio/cortex-engine) [](https://www.npmjs.com/package/@fozikio/cortex-engine) [](https://github.com/Fozikio/cortex-engine/stargazers) [](LICENSE)

Persistent memory for AI agents. Open source, LLM-agnostic, works with any MCP client.

Star History

What It Does

Most AI agents forget everything when the session ends. cortex-engine fixes that — it gives agents a persistent memory layer that survives across sessions, models, and runtimes.

• Semantic memory — store and retrieve observations, beliefs, questions, and hypotheses as interconnected nodes
• Belief tracking — agents hold positions that update when new evidence contradicts them
• Two-phase dream consolidation — NREM compression (cluster, refine, create) + REM integration (connect, score, abstract) — modeled on biological sleep stages
• Goal-directed cognition — goal_set creates desired future states that generate forward prediction error, biasing consolidation and exploration toward what matters
• Neuroscience-grounded retrieval — GNN neighborhood aggregation, query-conditioned spreading activation, multi-anchor Thousand Brains voting, epistemic foraging
• Information geometry — locally-adaptive clustering thresholds that respect embedding space curvature, schema congruence scoring
• Graph health metrics — Fiedler value (algebraic connectivity) measures knowledge integration; PE saturation detection prevents identity model ossification
• Spaced repetition (FSRS) — interval-aware scheduling with consolidation-state-dependent decay profiles
• Embeddings — pluggable providers (built-in, OpenAI, Vertex AI, Ollama) — no external service required by default
• LLM-agnostic — pluggable LLM providers: Ollama (free/local), Gemini, Kimi (Moonshot AI), DeepSeek, Hugging Face, OpenRouter, OpenAI, or any OpenAI-compatible API
• Three storage backends — local SQLite (default), cloud Firestore, and JSON file (backup/migration). All share one CortexStore interface — see [docs/storage-backends.md](docs/storage-backends.md)
• Atomic transactions — withTransaction(fn) primitive composes multi-step writes. SQLite uses BEGIN IMMEDIATE with a per-store mutex; Firestore uses runTransaction with a write-routing proxy. See [docs/concurrency.md](docs/concurrency.md)
• Migration tooling — fozikio migrate --from --to clones between any pair of backends. ID-preserving, checkpointed, resumable, fails-loud on schema mismatch
• Typed tool catalogue — every cognitive tool carries category + whenToUse + doNotUse metadata so LLMs disambiguate cleanly. Browse with fozikio tools or GET /tools. Auto-generated reference at [docs/tools-reference.md](docs/tools-reference.md)
• Long-context dream consolidation — set strategy: long-context to run edge discovery and abstraction in a single large LLM pass instead of N² pairwise calls; surfaces transitive patterns and cross-domain connections that the sequential approach misses
• Agent dispatch — agent_invoke lets your agent spawn cheap, cortex-aware sub-tasks using any configured LLM. Knowledge compounds across sessions.
• MCP server — 57 cognitive tools (query, observe, believe, wander, dream, goal_set, agent_invoke, thread_create, journal_write, evolve, etc.) over the Model Context Protocol

The result: personality and expertise emerge from accumulated experience, not system prompts. An agent with 200 observations about distributed systems doesn't need to be told "you care about distributed systems." It just knows.

Works with Claude Code, Cursor, Windsurf, or any MCP-compatible client. Runs locally (SQLite) or in the cloud (Firestore + Cloud Run).

Security

The engine includes defense-in-depth protections for deployed environments:

• Timing-safe auth — REST server authentication uses crypto.timingSafeEqual to prevent timing side-channel attacks
• Plugin sandboxing — the plugin loader validates import paths against trusted directories, blocking loads from untrusted locations
• REST tool blocklist — destructive tools (forget, dream, evolve, resolve, thread_resolve) are blocked from the generic REST endpoint; they remain available via MCP for direct agent access
• SQLite injection prevention — namespace names are validated (alphanumeric only), LIMIT clauses are parameterized
• Secret leak prevention — config loader warns when API keys appear in config files instead of environment variables

Architecture

| Module | Role | |--------|------| | core | Foundational types, config, and shared utilities | | engines | Cognitive processing: memory consolidation, FSRS, graph traversal | | stores | Persistence layer — SQLite (local), Firestore (cloud), JSON (backup/migration). All implement the shared CortexStore interface | | tools | All 57 cognitive tool implementations (one file per tool) | | mcp | MCP server, tool registry, and plugin loader | | cognitive | Higher-order cognitive operations (dream, wander, validate) | | triggers | Scheduled and event-driven triggers | | bridges | Adapters for external services and APIs | | providers | Embedding and LLM provider implementations | | bin | Entry points: serve.js (HTTP + MCP), cli.js (admin CLI) | | public | Built-in web dashboard (served automatically with --rest) |

Quick Start

npm install @fozikio/cortex-engine
npx fozikio init my-agent
cd my-agent
npx fozikio serve   # starts MCP server

Your agent now has 57 cognitive tools. The generated .mcp.json is version-pinned and platform-aware (Windows cmd /c wrapper handled automatically).

See the [Quick Start](docs/quick-start.md) guide for the full 5-minute setup.

Multi-Agent

npx fozikio agent add researcher --description "Research agent"
npx fozikio agent add trader --description "Trading signals"
npx fozikio agent generate-mcp   # writes .mcp.json with scoped servers

Each agent gets isolated memory via namespaces. See the [Architecture](#architecture) section for details.

Agent-First Setup

The fastest path: open an AI agent in an empty directory and say "set up a cortex workspace." The agent runs npx fozikio init, reads the generated files, and is immediately productive. See the [Agent-First Setup](docs/agent-first-setup.md) guide for the full walkthrough.

Dashboard

cortex-engine ships with a built-in web dashboard. Start the REST server and open the URL in your browser:

npx fozikio serve --rest --port 3000
# open http://localhost:3000

The dashboard shows your agent's stats, threads, ops log, memories, concepts, and observations — no separate install required. It auto-detects its API from the same origin it's served from.

If auth is enabled (CORTEX_API_TOKEN), the dashboard loads without auth but API calls require a token. Set it via localStorage:

localStorage.setItem("cortex-settings", JSON.stringify({ token: "your-token" }));

Source: fozikio-dashboard

CLI

npx fozikio serve                          # start MCP server
npx fozikio health                         # memory health report
npx fozikio vitals                         # behavioral vitals and prediction error
npx fozikio wander                         # walk through the memory graph
npx fozikio wander --from "auth"           # seeded walk from a topic
npx fozikio maintain fix                   # scan and repair data issues
npx fozikio report                         # weekly quality report
npx fozikio tools                          # browse the cognitive tool catalogue
npx fozikio tools --category memory        # filter to a category
npx fozikio migrate --from sqlite:./cortex.db --to json:./backup.json --verify

All read-only commands honour --namespace and --agent flags. When called from a workspace with .fozikio/agent.yaml, the agent's default_namespace is picked up automatically — no flag needed.

Development

npm run dev       # tsc --watch
npm test          # vitest run
npm run test:watch

Environment Variables

| Variable | Required | Description | |----------|----------|-------------| | CORTEX_API_TOKEN | Optional | Used by the cortex-telemetry hook to send retrieval feedback to the cortex API. Not required to run the MCP server. | | MOONSHOT_API_KEY | Optional | Required when llm: kimi is set. Get one from platform.moonshot.cn. | | OPENAI_API_KEY | Optional | Required when llm: openai is set, or when using any OpenAI-compatible provider without an explicit API key. |

Additional variables are required depending on which providers you enable (Firestore, Vertex AI, etc.). See docs/ for provider-specific configuration.

Rules, Skills & Agents

fozikio init automatically installs safety rules, skills, and agent definitions from the fozikio.json manifest into the target workspace.

Safety Rules (Reflex)

cortex-engine ships with Reflex rules — portable YAML-based guardrails that work across any agent runtime, not just Claude Code.

| Rule | Event | What It Does | |------|-------|-------------| | cognitive-grounding | prompt_submit | Nudges the agent to call query() before evaluation, design, review, or creation work | | observe-first | file_write / file_edit | Warns if writing to memory directories without calling observe() or query() first | | note-about-doing | prompt_submit | Suggests capturing new threads of thought with thread_create() |

Rules live in reflex-rules/ as standard Reflex YAML. They're portable — use them with Claude Code, Cursor, Codex, or any runtime with a Reflex adapter. See @fozikio/reflex for the full rule format and tier enforcement.

Claude Code users also get platform-specific hooks (in hooks/) for telemetry, session lifecycle, and project board gating. These are runtime adapters, not rules — they handle side effects that the declarative rule format doesn't cover.

To customize: Edit the YAML rule files directly, or set allow_disable: true and disable them via Reflex config.

Skills

Skills are invocable workflows that agents can use via /skill-name.

| Skill | When to Use | What It Provides | |-------|-------------|-----------------| | cortex-memory | Query, record, and review work | Full memory workflow — query/observe patterns, belief tracking, memory-grounded code review, session patterns |

Agents

| Agent | Description | |-------|-------------| | cortex-researcher | Deep research agent that queries cortex before external sources, observes novel findings back into memory |

How Auto-Install Works

1. fozikio init reads fozikio.json from the package root
2. Copies hooks, skills, and Reflex rules into the target workspace
3. Missing source files are skipped with a warning — init never fails due to missing assets

Built-in Capabilities (v1.0.0+)

As of v1.0.0, all 57 cognitive tools are built into cortex-engine core — no separate plugin installs needed. Previously these were separate @fozikio/tools-* packages; they've been absorbed into the engine.

| Capability | Tools | |-----------|-------| | Memory | observe, query, recall, wander, forget, retrieve | | Beliefs & Reasoning | believe, belief, contradict, speculate, validate, predict | | Threads | thread_create, thread_update, thread_resolve, threads_list | | Journaling | journal_write, journal_read | | Identity | evolve, evolution_list | | Social | social_read, social_update, social_draft, social_score | | Graph | neighbors, suggest_links, suggest_tags, link, graph_report | | Maintenance | dream, digest, reflect, find_duplicates, retrieval_audit, consolidation_status | | Vitals | vitals_get, vitals_set, sleep_pressure | | Reasoning | surface, ruminate, notice, intention, resolve | | Content | content_create, content_list, content_update | | Ops | ops_append, ops_query, ops_update | | Goals | goal_set | | Agents | agent_invoke | | Stats | stats |

The plugin system is still available for custom extensions — see Plugin Docs.

Documentation

• In-repo docs:
• [Quick Start](docs/quick-start.md) — 5-minute setup
• [Storage backends](docs/storage-backends.md) — SQLite vs Firestore vs JSON, migration paths
• [Concurrency model](docs/concurrency.md) — withTransaction contract, single-process invariant, SQLite vs Firestore semantics
• [Tools reference](docs/tools-reference.md) — all 57 tools by category with when-to-use guidance (auto-generated)
• [Multi-agent design](docs/multi-agent-design.md) — namespace isolation, bridges, federation
• [Design specs](docs/superpowers/specs/) — design documents from the v1.2.0 audit-driven refactor
• [Agent-first setup](docs/agent-first-setup.md) — Workspace initialization walkthrough
• Discussions — Ask questions, share what you've built
• Contributing — How to contribute
• Project Board — Roadmap and active work
• Security — Report vulnerabilities

Community

• r/Fozikio — Project subreddit
• GitHub Discussions — Questions, feedback, show what you've built
• "I built 44 MCP tools for my cognitive system" — r/mcp deep dive (84 upvotes, 27 comments)
• "Gave my agent a subconscious" — r/clawdbot walkthrough (22 upvotes, 34 comments)

Related Projects

• @fozikio/reflex — Portable safety guardrails for agents. Rules as data, not code.
• sigil — Agent control surface. Signals and gestures, not conversations.
• fozikio.com — Documentation and guides

License

MIT — see [LICENSE](LICENSE)

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Fozikio
• Source: Fozikio/cortex-engine
• License: MIT

Install and usage instructions live in the source repository linked above.