> ## 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 Session Coordinator for Symphony Vector Engines

> The Knowledge Session Coordinator provides bounded compatibility, worktree reconciliation, authenticated sessions, and apply-capable lifecycle coordination in C++26.

The Knowledge Session Coordinator (`modules/knowledge-session-coordinator`) is an independently installable C++26 process. It sits between qxctl and the vector engines and owns bounded compatibility, worktree reconciliation, authenticated noncanonical sessions, SSFV maintenance, report-only lifecycle planning, and separately authorized apply-capable journals.

## Responsibilities

* **Compatibility checks** between qxctl, coordinator, and engines
* **Worktree reconciliation** with durable slot-based state
* **Authenticated noncanonical sessions** under SSIAG authority
* **Persistent SSFV maintenance** streams
* **Report-only lifecycle planning** with deterministic evidence
* **Apply-capable journals** with prepared attempts, compare-and-swap, re-observation, dynamic replanning, and recovery

## What the coordinator does not do

<Warning>
  The coordinator does not execute vector semantics or host actions. It coordinates evidence and journals; each engine still owns its domain, and each host action stays authorized by its own contract.
</Warning>

* No canonical knowledge apply
* No arbitrary command execution
* No hidden watchers or resident background work

## qxctl integration

qxctl invokes exact receipt-validated coordinator installations. `qxctl knowledge reconcile ...` and `qxctl knowledge session ...` use one exact bound coordinator per operation, and mutations require stable operation identifiers plus exact current journal digests for compare-and-swap.

## Related surfaces

<CardGroup cols={2}>
  <Card title="qxctl reconcile" icon="arrows-rotate" href="/symphony/symphony/qxctl/reconcile">
    Worktree reconciliation grammar.
  </Card>

  <Card title="qxctl session" icon="key" href="/symphony/symphony/qxctl/session">
    Authenticated session and SSFV maintenance grammar.
  </Card>

  <Card title="Foundation library" icon="cube" href="/symphony/symphony/engines/knowledge-vector-foundation">
    Shared C++ mechanics the coordinator reuses.
  </Card>

  <Card title="SSIAG" icon="shield-halved" href="/symphony/symphony/governance/ssiag">
    Authorizes the sessions the coordinator manages.
  </Card>
</CardGroup>


## Related topics

- [SKVI: The Symphony Knowledge Vector Index Engine](/symphony/symphony/skv/skvi.md)
- [qxctl knowledge session: Authenticated Symphony Sessions](/symphony/symphony/qxctl/session.md)
- [Knowledge Vector Engine C++ Foundation: Shared Mechanics](/symphony/symphony/engines/knowledge-vector-foundation.md)
- [Symphony Vector Engines: Independent Installation Overview](/symphony/symphony/engines/overview.md)
- [qxctl knowledge reconcile: Worktree Reconciliation](/symphony/symphony/qxctl/reconcile.md)