FastMCP
Latest release v4.0.5 on 2026-09-17 · Actively maintained · 15 releases in 90 days
🚀 The fast, Pythonic way to build MCP servers and clients.
| Latest release | v4.0.5 on 2026-09-17 |
|---|---|
| Maintenance | Actively maintained — pushed within the last 14 days, with 3 or more releases in 90 days |
| Stars | 27,835 |
| Releases in 90 days | 15 |
| Last commit | 2026-09-21 |
| Repository | PrefectHQ/fastmcp |
| Licence | Apache-2.0 |
| Open issues | 360 |
Recent releases
v4.0.5 2026-09-17
What's new
- Add regression test for the unconfigured ID-JAG guard
Fixed
- Preserve field-level strict validation in lax mode
Changed
- Add v4.0.5 changelog entries
v4.0.4 2026-09-16
Fixed
- Resolve ty 0.0.79 warnings from upgrade checks
- OAuthProxy accepts self-contained ID-JAG tokens even when identityass
- Fix upgrade checks for the M2M storage warning test
- Fix OpenAPI query explode defaults
Changed
- Update CodeMode for pydantic-monty 0.0.21
- Update github actions (major) by [bot]
- Add v4.0.4 changelog entries
v4.0.3 2026-09-05
Fixed
- Don't infer an output schema for unconstrained sequences
- Clean up unfinished Monty callbacks
- Fix task timing field serialization
Faster
- Avoid duplicate startup for mixed-era backends
Maintenance status is derived from public repository activity — release cadence and commit recency. It is not a review, an endorsement, or a security assessment. Star counts measure attention, not quality.