> Markdown version of [/events/world-congress-2026-north-america/sessions/1823-vector-graph-or-key](https://www.wearedevelopers.com/events/world-congress-2026-north-america/sessions/1823-vector-graph-or-key). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md).

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# Vector, Graph, or Key Value? Choosing Your Agent's Memory


- **Event:** World Congress 2026 North America

## Description

Your agent works in the demo, then forgets everything the next day. The model is not broken: models are stateless by design, and memory belongs to the harness you build around them. Bigger context windows do not fix it. Re sending full history burns tokens every turn and still vanishes between sessions.

This talk maps the agent memory landscape through one question asked four ways: retrieval by key, by meaning, and by relationship. You will learn when key value, vector, graph, and hybrid memory each win, plus the capabilities layer on top: selective memory, hygiene against dirty and poisoned entries, and reasoning memory for auditable decisions.

## Speaker

### [Elizabeth Fuentes Leone](https://www.wearedevelopers.com/@elizabeth-fuentes-leone)

AWS - Developer Advocate/SDE, GenAI


## Related talks at this congress

- [Building World-Aware Robots with Agent Memory and Context Graphs](https://www.wearedevelopers.com/events/world-congress-2026-north-america/sessions/1746-building-world-aware) — Zaid Zaim
- [Your Agents Need Observability Before They Need Better Models](https://www.wearedevelopers.com/events/world-congress-2026-north-america/sessions/1825-your-agents-need) — Julia Furst Morgado
- [Context Engineering: How machines remember and forget](https://www.wearedevelopers.com/events/world-congress-2026-north-america/sessions/1765-context-engineering) — Emre Okcular
- [Context Engineering Kung Fu](https://www.wearedevelopers.com/events/world-congress-2026-north-america/sessions/1410-context-engineering) — Carl Lapierre

## Watch remotely

Can’t make it to San José? Watch this session live with Pro. You also get:

- All full videos, bookmarks, and playlists
- World Congress livestreams

[See pricing](https://www.wearedevelopers.com/pricing)

## Links

- [Get tickets](https://www.wearedevelopers.com/world-congress-north-america/tickets)