Compare frameworks
Instructor vs Mastra 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 | Instructor | Mastra | Vercel AI SDK |
|---|---|---|---|
| Stars | 13,939Synced from sourceCurrent2h ago | 28,295 (highest of the compared values)Synced from sourceCurrent2h ago | 26,922Synced from sourceCurrent2h ago |
| downloads | 13,080,962Synced from sourceStale1mo ago· past SLA | 1,161,907Synced from sourceCurrent2h ago | 17,883,737 (highest of the compared values)Synced from sourceCurrent2h ago |
| Last commit | 2026-09-22Synced from sourceCurrent2h ago | 2026-09-24Synced from sourceCurrent2h ago | 2026-09-24Synced from sourceCurrent2h ago |
| Language | pythonSeeded, unreviewedwritten 1mo ago | typescriptSeeded, unreviewedwritten 1mo ago | typescriptSeeded, unreviewedwritten 1mo ago |
| Licence | MITSynced from sourceCurrent2h ago | — | — |
| Archived | noSynced from sourceCurrent2h ago | noSynced from sourceCurrent2h ago | noSynced from sourceCurrent2h ago |
| Category | structured-outputSeeded, unreviewedwritten 1mo ago | orchestrationSeeded, unreviewedwritten 1mo ago | orchestrationSeeded, unreviewedwritten 1mo ago |
| Contributors | 267Synced from sourceCurrent2h ago | 678Synced from sourceCurrent2h ago | 715Synced from sourceCurrent2h ago |
| Forks | 1262Synced from sourceCurrent2h ago | 2845Synced from sourceCurrent2h ago | 5180Synced from sourceCurrent2h ago |
| Maintainer | 567 LabsSeeded, unreviewedwritten 1mo ago | MastraSeeded, unreviewedwritten 1mo ago | VercelSeeded, unreviewedwritten 1mo ago |
| npm downloads, monthly | — | 5528725Synced from sourceCurrent2h ago | 87791075Synced from sourceCurrent2h ago |
| npm downloads, weekly | — | 1161907Synced from sourceCurrent2h ago | 17883737Synced from sourceCurrent2h ago |
| npm package | — | @mastra/coreSynced from sourceCurrent2h ago | aiSynced from sourceCurrent2h ago |
| npm window ends | — | 2026-09-21Synced from sourceCurrent2h ago | 2026-09-21Synced from sourceCurrent2h ago |
| Open issues | 90Synced from sourceCurrent2h ago | 447Synced from sourceCurrent2h ago | 1462Synced from sourceCurrent2h ago |
| PyPI downloads, monthly | 27671654Synced from sourceStale1mo ago· past SLA | — | — |
| PyPI downloads, weekly | 13080962Synced from sourceStale1mo ago· past SLA | — | — |
| PyPI package | instructorSynced from sourceCurrent2h ago | — | — |
| PyPI released | 2026-09-09T02:25:54.888746ZSynced from sourceCurrent2h ago | — | — |
| Requires Python | <4.0,>=3.9Synced from sourceCurrent2h ago | — | — |
| PyPI version | 1.17.0Synced from sourceCurrent2h ago | — | — |
| Repository | https://github.com/567-labs/instructorSynced from sourceCurrent2h ago | https://github.com/mastra-ai/mastraSynced from sourceCurrent2h ago | https://github.com/vercel/aiSynced from sourceCurrent2h ago |
Sources: GitHub REST API, npm registry downloads, PyPI registry metadata, pypistats.org downloads. Most recent observation 2h 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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