# Letta vs Vespa — Fit & Features

Canonical: https://trutool.co/compare/letta-vs-vespa
Author: Snehil (https://trutool.co/authors/snehil)

Compare Letta and Vespa by use case, features, limitations, and evaluation questions.

## Compare fit, features, and limitations

### Letta
Build agents that retain and manage state and memory across interactions.
Best fit: Developers building grounded assistants with persistent context and retrieval.
- Stateful agents
- Agent memory
- Agent APIs
Before you choose: Test retrieval quality, deletion behavior, access boundaries, and retention. Compare hosting and embedding costs for your data.
Pricing: https://www.letta.com
- [Read Letta profile](https://trutool.co/tools/letta): Read Letta profile

### Vespa
Build scalable search and recommendation applications with vector and keyword retrieval.
Best fit: Developers building grounded assistants with persistent context and retrieval.
- Hybrid search
- Ranking
- Vector retrieval
Before you choose: Test retrieval quality, deletion behavior, access boundaries, and retention. Compare hosting and embedding costs for your data.
Pricing: https://vespa.ai/pricing/
- [Read Vespa profile](https://trutool.co/tools/vespa): Read Vespa profile