> ## Documentation Index
> Fetch the complete documentation index at: https://docs.brik64.com/llms.txt
> Use this file to discover all available pages before exploring further.

# EVA

> BRIK64 composition model.

EVA is the BRIK64 composition model for explaining how circuit units connect.

It gives agents three structural forms:

* sequential flow;
* conditional branch selection;
* parallel independent branches.

## Why EVA Matters

PCD describes operations. EVA explains how those operations compose.

Without EVA structure, an agent may generate code that works locally but is hard to inspect as a circuit.

## Public Authoring Guidance

In public PCD examples, represent EVA through explicit source structure and topology metadata unless a release documents a supported symbolic syntax.

## Reading Path

* [EVA Tutorial](/eva/tutorial)
* [Sequential Composition](/eva/sequential)
* [Conditional Composition](/eva/conditional)
* [Parallel Composition](/eva/parallel)