Compare frameworks
Letta vs LlamaIndex vs Vercel AI SDK
Every figure below carries the source that reported it and the moment it was observed. Values that failed validation are withheld rather than shown, and a dash means no source we track carries that field for that framework.
| Field | Letta | LlamaIndex | Vercel AI SDK |
|---|---|---|---|
| Stars | 25,382Synced from sourceCurrent3h ago | 52,842 (highest of the compared values)Synced from sourceCurrent3h ago | 27,805Synced from sourceCurrent3h ago |
| downloads | — | 179,093Synced from sourceCurrent3h ago | 45,262,880 (highest of the compared values)Synced from sourceCurrent3h ago |
| Last commit | 2026-10-18Synced from sourceCurrent3h ago | 2026-11-06Synced from sourceCurrent3h ago | 2026-11-07Synced from sourceCurrent3h ago |
| Language | pythonSeeded, unreviewedwritten 2mo ago | pythonSeeded, unreviewedwritten 2mo ago | typescriptSeeded, unreviewedwritten 2mo ago |
| Licence | Apache-2.0Synced from sourceCurrent3h ago | MITSynced from sourceCurrent3h ago | — |
| Archived | noSynced from sourceCurrent3h ago | noSynced from sourceCurrent3h ago | noSynced from sourceCurrent3h ago |
| Category | memorySeeded, unreviewedwritten 2mo ago | ragSeeded, unreviewedwritten 2mo ago | orchestrationSeeded, unreviewedwritten 2mo ago |
| Contributors | 155Synced from sourceCurrent3h ago | 2008Synced from sourceCurrent3h ago | 783Synced from sourceCurrent3h ago |
| Forks | 2667Synced from sourceCurrent3h ago | 8532Synced from sourceCurrent3h ago | 5549Synced from sourceCurrent3h ago |
| Maintainer | LettaSeeded, unreviewedwritten 2mo ago | LlamaIndexSeeded, unreviewedwritten 2mo ago | VercelSeeded, unreviewedwritten 2mo ago |
| npm downloads, monthly | — | 620141Synced from sourceCurrent3h ago | 145134192Synced from sourceCurrent3h ago |
| npm downloads, weekly | — | 179093Synced from sourceCurrent3h ago | 45262880Synced from sourceCurrent3h ago |
| npm package | — | llamaindexSynced from sourceCurrent3h ago | aiSynced from sourceCurrent3h ago |
| npm window ends | — | 2026-11-06Synced from sourceCurrent3h ago | 2026-11-06Synced from sourceCurrent3h ago |
| Open issues | 0Synced from sourceCurrent3h ago | 1320Synced from sourceCurrent3h ago | 1505Synced from sourceCurrent3h ago |
| PyPI package | lettaSynced from sourceCurrent3h ago | llama-indexSynced from sourceCurrent3h ago | — |
| PyPI released | 2026-10-12T20:47:35.858621ZSynced from sourceCurrent3h ago | 2026-09-21T16:22:20.056831ZSynced from sourceCurrent3h ago | — |
| Requires Python | >=3.9Synced from sourceCurrent3h ago | <4.0,>=3.10Synced from sourceCurrent3h ago | — |
| PyPI version | 0.34.12Synced from sourceCurrent3h ago | 0.14.25Synced from sourceCurrent3h ago | — |
| Repository | https://github.com/letta-ai/lettaSynced from sourceCurrent3h ago | https://github.com/run-llama/llama_indexSynced from sourceCurrent3h ago | https://github.com/vercel/aiSynced from sourceCurrent3h ago |
Sources: GitHub REST API, npm registry downloads, PyPI registry metadata, pypistats.org downloads. Most recent observation 3h ago. Where a row is marked, ▲ is the highest of the values shown and ▼ the lowest — arithmetic on the figures above, not a ranking or a recommendation. Rows where neither extreme is meaningful are left unmarked rather than given a direction they do not have.
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