RuVector 0.2.40: MetaHarness, Darwin, and Flywheel
RuVector 0.2.40 makes its research and optimization control plane available
through the npm SDK, CLI, and MCP server. The integration uses pinned, direct
dependencies so an installed package has the same capability set that was
tested for the release.
Install
npm install ruvector@0.2.40Node.js 20 or newer is required.
Check the installation
npx ruvector harness doctor --jsonThe doctor loads and checks all nine pinned capabilities:
- MetaHarness core
- Darwin
- Flywheel
- algorithmic harness kernel
- cost-aware router
- Red/Blue safety controls
- Weight-EFT reward-hack detection
- workspace lens
- workspace probe
Use the SDK
All new APIs are exported from the main ruvector package:
const {
getMetaHarnessCapabilities,
routeWithMetaHarness,
evaluateMetaHarnessPromotion,
verifyMetaHarnessReplay,
} = require('ruvector');
const capabilities = await getMetaHarnessCapabilities();
const route = await routeWithMetaHarness({
rows: [
{
embedding: [1, 0],
scores: { economical: 0.91, frontier: 0.99 },
},
],
prices: { economical: 1, frontier: 20 },
queryEmbedding: [1, 0],
qualityBar: 0.9,
});
console.log(route);
// { id: "economical", predictedQuality: 0.91, costPerMTok: 1, metBar: true }Additional SDK entry points support:
- Flywheel generation runs and signed replay verification
- explicit Darwin evolution runs
- frozen promotion-gate evaluation
- algorithmic harness construction
- workspace receipt scoring
- reward-hack trajectory scanning
- live-credential guards
Darwin will not execute unless the caller explicitly supplies
{ execute: true }.
Use the CLI
Route by quality and cost
Prepare three JSON files:
[
{
"embedding": [1, 0],
"scores": {
"economical": 0.91,
"frontier": 0.99
}
}
]{
"economical": 1,
"frontier": 20
}[1, 0]Then route:
npx ruvector harness route \
--examples examples.json \
--prices prices.json \
--query query.json \
--quality-bar 0.9Verify research evidence
npx ruvector harness flywheel verify replay-bundle.json
npx ruvector harness flywheel gate promotion-evidence.jsonRun Darwin explicitly
npx ruvector harness darwin evolution-config.json --executeThe --execute requirement is deliberate because Darwin candidates can run
code. Review the configuration and sandbox policy before authorizing a run.
Use MCP safely
Start the MCP server with the curated read-only profile:
RUVECTOR_MCP_PROFILE=readonly npx ruvector mcp startThe profile exposes six non-executing MetaHarness tools:
metaharness_statusmetaharness_routemetaharness_replay_verifymetaharness_flywheel_gatemetaharness_workspace_probemetaharness_reward_hack_scan
Darwin execution and Flywheel mutation loops are intentionally not exposed over
MCP. They remain explicit SDK/CLI authority boundaries.
Upgrade notes
- Node.js 20+ is now required.
- MetaHarness packages are direct dependencies and are installed with RuVector.
- Dependencies are loaded lazily, keeping ordinary RuVector startup fast.
- Existing vector database APIs remain available from the same package entry
point.
Verification
The published tarball was installed into a clean project before release. The
release passed the full npm suite, SDK/CLI/MCP integration checks, MCP handshake
and policy checks, distribution verification, startup-budget checks, and a
production dependency audit with zero reported vulnerabilities.