> ## Documentation Index
> Fetch the complete documentation index at: https://docs.quanux.org/symphony/llms.txt
> Use this file to discover all available pages before exploring further.

# Knowledge Vector Engine C++ Foundation: Shared Mechanics

> The Knowledge Vector Engine C++ foundation supplies authority-free process framing, bounded JSON, SHA-256, snapshots, receipts, and explicit manifest discovery.

`libraries/knowledge-vector-engine-cpp` supplies the shared, authority-free C++ mechanics that every Symphony vector engine reuses. It provides deterministic building blocks so each engine can stay bounded, reproducible, and free of ambient side effects.

## What the foundation provides

* **Process framing**: authority-free local process protocol used by every engine
* **Bounded JSON**: strict parsing and emission with explicit size and depth limits
* **SHA-256**: content addressing for evidence and receipts
* **No-follow reads**: filesystem reads that never traverse symbolic links unexpectedly
* **Deterministic snapshots**: repeatable snapshots of inspected state
* **Temporal validation**: canonical UTC handling per the Symphony Temporal Semantics Contract
* **Owner-manifest discovery**: exact discovery of contract manifests
* **Versioned packaging**: independently installable receipt-owned packages
* **Receipts and receipt-owned uninstall**: uninstall driven only by the receipt that installed the artifact

## Manifest discovery boundary

<Warning>
  Manifest discovery begins from a fixed bootstrap set and traverses only explicit subordinate declarations. It never performs an ambient repository crawl or infers ownership from directory names.
</Warning>

Every vector engine that consumes the foundation inherits this rule.

## What the foundation does not do

* It does not carry authority. Engines that use it must still authorize mutations through SSIAG.
* It does not publish or fetch anything over the network.
* It does not mutate canonical files on its own.

## Related surfaces

<CardGroup cols={2}>
  <Card title="Session coordinator" icon="gears" href="/symphony/symphony/engines/coordinator">
    C++26 coordinator built on the foundation for sessions and reconciliation.
  </Card>

  <Card title="Engines overview" icon="cube" href="/symphony/symphony/engines/overview">
    The engines that reuse the foundation.
  </Card>

  <Card title="SKV overview" icon="book-open" href="/symphony/symphony/skv/overview">
    Vector contracts that the engines implement.
  </Card>

  <Card title="qxctl overview" icon="terminal" href="/symphony/symphony/qxctl/overview">
    Administrative CLI that invokes exact receipt-validated engines.
  </Card>
</CardGroup>


## Related topics

- [Knowledge Session Coordinator for Symphony Vector Engines](/symphony/symphony/engines/coordinator.md)
- [Symphony Vector Engines: Independent Installation Overview](/symphony/symphony/engines/overview.md)
- [Maestro: Symphony Vector-Engine Presence Authority](/symphony/symphony/governance/maestro.md)
- [SCV Source-Knowledge Engines: Provider Reality for Symphony](/symphony/symphony/engines/scv-source-engines.md)
- [Symphony Vectors and Delivery Phases](/symphony/symphony/concepts/vectors.md)