Updated: 2026-10-10 10:41:47 EDT | Version 4.6.2 Created: 2026-06-29 22:36:38 EDT

🧠 RuvNet Brain

Discover the stack. Read the source. Build with confidence.

A source-grounded companion for Claude Code and Codex that helps you find and use Reuven Cohen's (rUv's) RuvNet ecosystem.

▶ Explore the visual walkthrough

Built by Stuart Kerr at Isovision.ai · open source · MIT licensed

The RuvNet ecosystem spans agent orchestration, vector search, memory, model routing, testing and more. Finding the right building block is often harder than writing the first line of code. Brain puts the source within reach of your coding assistant and helps it recognize capabilities you may not yet know to ask for.

Ask for the outcome you want. Brain helps connect it to the real tools and code.

Our north star: useful capability discovery. A good answer should explain what helps, why it fits, where it is implemented, and what remains unproven. Retrieval supports that conversation; the goal is helping you build.

Get started · Try it · How it works · Capabilities · Updates · Evidence

What is Brain?

Brain brings three things together:

• A local knowledge bundle built from public RuvNet source and documentation, with searchable passages, source paths, implementation bodies, symbols and capability cards.
• A coding companion delivered through native Claude Code and Codex plugins: the search_ruvnet MCP tool, skills and lifecycle hooks that encourage source-grounded work.
• A local control panel, the RuvNet Brain Console (RNBC), for inspecting your installed environment, choosing supported settings and seeing what actually ran.

It gives the assistant a practical way to read the stack instead of relying on remembered APIs. You can ask by product name, describe a problem, or ask where a capability is implemented. Results identify the repository and file so the answer can be checked.

You keep control. Recommendations, saved settings, executed tools and verified outcomes are different things. Brain's evidence surfaces are designed to show those differences.

Get started

You need Node.js 18 or newer, npm, and a supported Claude Code or Codex installation. Run the installer from your terminal:

npx ruvnet-brain@latest

The installer downloads the signed public knowledge bundle, installs its local reader and configures the supported hosts it detects. The default Brain home is ~/.cache/ruvnet-brain; the knowledge bundle lives in its kb/ directory. Follow the installer's host/trust instructions and restart when it reports changed plugin declarations.

Local knowledge retrieval does not require an external embedding API or its API key. Installation and updates download dependencies and release artifacts; your coding host and any optional model providers retain their own account and billing requirements.

Then ask your assistant:

How does Ruflo coordinate agents? Show the source that implements it.

Open the Console in Claude Code or Codex with /rnbc (also /rnb). It opens a local page and scans your environment. Actions explain their effect before you apply them.

For an installed command, inspect the actual installation:

ruvnet-brain --doctor

If you used the one-shot installer and have no ruvnet-brain command on your PATH, use npx ruvnet-brain@latest --doctor. Keep routine updates on the installation's existing owner and path; see stay current.

The installer and local search support macOS, Linux and Windows. Hook delivery and optional executors depend on the host, OS and installed tools. Use --doctor and actual task receipts to inspect your environment; a registered hook or tool alone does not establish delivery.

Try it on your next task

You do not need to know the repository names first. Start with a concrete need:

• Find a building block: “I need persistent memory for my agents. Which RuvNet options fit, and where are their APIs implemented?”
• Understand a mechanism: “Show me how RVF stores and queries vectors. Cite the source, and separate working implementation from design documents.”
• Plan with evidence: “Compare the RuvNet approaches for routing model calls. Explain the tradeoffs before recommending one.”
• Improve a codebase: “Review this project's agent workflow. Identify a useful capability we already have, then propose the smallest change and how we would verify it.”
• Build with a bounded request: “Use /brain-build to add a read-only report to this app, keep existing data intact, and verify the rendered result.”
• Resume work: “Come up to speed on this project: what changed, what is still open, and which decisions have source or test evidence?”

These are starting prompts, not promises of a particular result. Ask the assistant to cite what it read, say which tools executed, and name any missing prerequisite. Optional routing requires available, authorized executors; recommendations do not automatically install tools or authorize spending.

How it works

Brain separates building the knowledge, retrieving evidence, and acting on it. Public source is indexed into local RVF stores. At query time, the reader combines routing and retrieval lanes, reranks candidates and returns source evidence through MCP. The coding host uses that evidence while its own tools perform the work.

PUBLIC KNOWLEDGE                      YOUR LOCAL WORKFLOW
RuvNet source + docs                  Your task in Claude Code / Codex
          |                                         |
          v                                         v
Index source + symbols                Skills + lifecycle guidance
          |                                         |
          v                                         v
Signed public bundle ---------------> search_ruvnet (MCP)
Local RVF stores + source passages    Route -> retrieve -> rerank
                                                    |
                                                    v
                                      Source evidence: repo + path
                                                    |
                                                    v
                                      Host tools / authorized executors
                                                    |
                                                    v
                                      Changes + checks + receipts
                                      Eligible project memory (AgentDB)

The reader uses per-repository knowledge, capability cards, lexical and vector retrieval, and a shared cross-encoder ranking lane. It labels evidence and checks implementation requirements for queries that ask for code. A capability card helps find a product; it does not by itself prove an implementation exists.

The public bundle contains RVF knowledge stores and source-passage sidecars. Project history is separate: eligible capture and recall use the project's canonical AgentDB store, including worktree resolution. Consent and failure reporting apply at those boundaries.

Source: retrieval implementation, MCP server, Claude hooks, Codex hooks.

What Brain brings to your workflow

Discover capabilities. Ask about a need in plain language and get a starting point in the RuvNet ecosystem. Source-grounded advocacy aims to surface relevant capabilities early, with a reason they fit your task.

Read implementation. Search results can include code bodies and source documents, with repository/path labels and evidence metadata. Evidence class matters: a design proposal and an implementation answer carry different weight.

Guide work across hosts. The plugins share grounding and workflow skills while native hook adapters account for Claude Code and Codex differences. /brain-prompt helps refine a rough idea; /brain-build supplies a structured build contract. Configured routing can hand bounded work to supported native executors and record the choice. Routing registration is separate from observing a worker execute.

Retain useful project context. Where an eligible project store and consent permit it, lifecycle capture records bounded, redacted observations and outcomes. Recall brings project facts and lessons back as evidence. Pending writes and incomplete restoration stay visible; inferred lessons do not silently become authoritative user instructions.

Inspect and maintain your environment. RNBC shows installed components and supported settings. The coordinated updater uses one policy and shared owner lock for manual and scheduled runs, preserving existing managers and install paths.

Make proof part of the conversation. Doctor, grounding receipts, update receipts and release gates distinguish a configured capability from an observed result. They help you identify the next check rather than infer success from a green registration line.

Explore the ecosystem through Brain

Ask about Ruflo for coordination, RuVector / RVF for vector knowledge, AgentDB for agent memory, agentic-flow for agent/model workflows, Agentic QE for quality engineering, or SPARC for a structured development method. Then deepen the answer with “show the implementation and prerequisites.” The bundle covers many more public repositories; its release census and source metadata define its coverage.

From a question to reviewable work

ASK          DISCOVER       READ          ACT          VERIFY
Your need -> Relevant    -> Source     -> Authorized -> Actual result
             capability     + limits      host tools    + limitations
                               ^                             |
                               |                             v
                         Next task <---------------- Project evidence
                                                     eligible memory

Start with the problem. Check the recommendation against its source. Make the change within the requested scope. Inspect the actual result, then retain useful evidence for the next task. The same sequence works for an explanation, a small repair or a larger delegated build.

Stay current

4.6.0 introduces coordinated installed-tool updates. Open RNBC and choose Keep all tools updated, with Latest (recommended) or Alpha. The default scope is the installed RuvNet suite; broader developer-tool maintenance is an explicit choice. Manual and scheduled runs share the coordinator, saved policy and owner lock. The schedule is 03:30 in your local time.

ruvnet-brain-update --check
ruvnet-brain-update --apply

Inspect the run receipt for what changed, failed or was excluded. A saved preference or a registered schedule establishes configuration; a completed run establishes its outcome. For an existing Brain installation, ruvnet-brain --update uses the update path. ruvnet-brain --disable-nightly disables its scheduled updates.

Code version and knowledge freshness are separate. A code release can package the last published corpus without having refreshed every upstream repository. Public corpus production uses the protected release workflow; a consumer update downloads an available generation and does not rebuild upstream knowledge. Check --doctor, SOURCE.json and refresh receipts before treating an installation as current.

The 4.6.0 published-corpus baseline is 205 public stores · 166,081 public source chunks. Those are bundle census values, not a claim that every upstream repository is fresh today. Later corpus publication may advance the knowledge generation independently of code changes.

See 4.6.2 native update repair notes, 4.6.1 README/admin notes and 4.6.0 coordinated-update notes and the authoritative update and release policy.

Evidence and honest limits

Brain supplies mechanisms and evidence; every claim has a boundary:

• Grounding guides the assistant. Hooks and skills encourage source reads. Selected tool boundaries can refuse a call, but they do not guarantee the model always obeys, writes correct code or chooses the best design.
• Retrieval has a snapshot boundary. Check dates and upstream source when currency matters. Coverage is limited to the indexed public material; the private-store fence excludes designated private stores from public bundles.
• Local search and model execution have different costs. The reader runs locally; your host and optional provider calls may be metered. Brain does not claim automatic model switching or savings from merely registering a route.
• Memory has consent and delivery boundaries. Queued capture is not committed history. Native delivery, exact readback and restoration require their own evidence.
• Publication is separate from source preparation. The protected workflow binds a release to its artifact and public installation checks. A README edit, local test or passing subset does not establish a published release.

This retained badge is a recorded baseline, not a new measurement from this documentation revision. npm run test:cov creates the coverage artifact; npm run claims:verify checks the advertised number against the source-bound artifact. A new release must rederive its claims. Historical routing percentages and test totals are deliberately absent from this overview: their original runs do not establish the current candidate's behavior.

For contributors

The repository uses Node.js ESM. Start with CONTRIBUTING.md, which owns release, versioning, corpus and hook policies. Install checkout dependencies and run the relevant checks:

npm ci
npm test
npm run single-source:check
npm run wired:check

Source and integration qualification are defined by npm run release:qualify; use the current procedure and unique report paths in CONTRIBUTING. Claims, packed-artifact checks, public installation and native-host evidence remain separate gates.

Useful places to read:

• plugin/ — native plugins, skills, lifecycle hooks and MCP shell.
• kb/ — retrieval implementation and knowledge tooling.
• scripts/ — install, update, console and release checks.
• docs/adr/ — architecture decisions and their acceptance limits.
• SECURITY.md — security boundaries and reporting.
• explainer/ — source for the public visual walkthrough. The companion page is introductory; current implementation and policy are documented in this repository.

Community and license

Have a concrete example that helped, or a source-grounded failure we can reproduce? Open an issue or join Discussions.

RuvNet Brain is MIT licensed. See LICENSE.