---
type: "Concept"
title: "The missing collaborative-learning layer"
description: "Orchestration standards don't define how institutions jointly improve a model."
tags: [theme, federated, architecture]
generated: { by: human:crpage, at: 2026-07-09T09:44:00Z }
status: stable
---

[MCP](../../standards/mcp.md) and [Arazzo](../../standards/arazzo.md) standardise interaction and workflow composition, but neither defines how remote parties **train or evaluate a shared model while keeping data local**. That is a distinct architectural layer — [the federation layer](../../stack/federation-layer.md) — which [federated learning](../../federated/federated-learning.md) frameworks such as [Flower](../../frameworks/flower.md) make explicit.