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# Build a Multi-Agent Marathon Planner with ADK and A2A


- **Date:** Thursday, Jul 9, 2026
- **Time:** 10:30–12:30 (120 min)
- **Room:** Room M1 (60 Seats)
- **Event:** World Congress 2026 Europe

## Description

In this codelab, you build a multi-agent system where three specialized AI agents collaborate to plan a city marathon. A Marathon Planner agent orchestrates the design, an Evaluator agent scores plan quality using Gemini Entreprise Agent Platform Evaluation, and a Simulation Controller agent validates readiness — all communicating through the Agent-to-Agent (A2A) protocol.

## Speakers

### [Abdelfettah Sghiouar](https://www.wearedevelopers.com/@abdelfettah-sghiouar)

Senior Cloud Developer Advocate at Google
### [Riccardo Carlesso](https://www.wearedevelopers.com/@riccardo-carlesso)

Developer Advocate at Google


## Related talks at this congress

- [Agents at Scale: Multi-Agent Architecture with A2A Protocol on Agent Runtime and ADK Integration](https://www.wearedevelopers.com/events/world-congress-2026-europe/sessions/1234-agents-at-scale) — Javier Cañadillas, Daniel Strebel
- [Building Multi-Agent Systems with Microsoft Agent Framework](https://www.wearedevelopers.com/events/world-congress-2026-europe/sessions/1293-building-multi-agent) — Kiran Panchal, Ricardo Niepel, Isha Salania
- [Create Your Own Role-Playing Game with Agentic AI using Strands Agents](https://www.wearedevelopers.com/events/world-congress-2026-europe/sessions/1288-create-your-own-role) — Arnaud Jean
- [Build a Multi-Channel AI Agent](https://www.wearedevelopers.com/events/world-congress-2026-europe/sessions/1354-build-a-multi) — Anni Chen