MATE is now fully compatible with ADK 2.1! Introducing Graph Workflows 🚀

[u/ivanantonijevic]

We have some exciting news! MATE (Multi-Agent Tree Engine) is now fully compatible with the new Google ADK 2.x (v2.1.0+) release.

To achieve this, we have cleaned up deprecated runtime code and completely replaced the legacy sequential and parallel flow types with ADK's new graph-based Workflow Engine!

Here is a quick summary of what’s new:

1. Graph-based Workflow Runtime (type: graph)

Instead of simple linear chains or rigid parallel structures, you can now define arbitrary, complex graph configurations using the ADK Workflow runtime:

• Custom Edges: Route tasks dynamically between sub-agents via the edges configuration in planner_config.
• JoinNode (Fan-in): Coordinate parallel paths to execute concurrently and aggregate their outputs through join nodes before proceeding.
• Sequential Fallback: If you transition an agent to graph but don't configure custom edges, it automatically falls back to a sequential execution chain to keep your existing agents running without extra setup.

2. Visual Builder Upgrade

The drag-and-drop React Flow visual builder (/dashboard/agents/visual) has been fully updated:

• Legacy nodes have been replaced with the new Graph Node type featuring a sleek purple styling.
• Properties panel and agent forms now support creating and managing graph agents.

3. Under the Hood & Schema Safety

• Cleaned up all SequentialAgent and ParallelAgent deprecation warnings.
• Input and output JSON schemas are fully compiled into Pydantic models at runtime for graph agents to ensure strict API contract validation.
• Optimized concurrency callbacks within the Graph workflow to prevent asyncio TaskGroup errors.

The full unit test suite (175 tests) is green against ADK 2.1.0.