FastMCP

v4.3.0 Feature

This release adds 1 notable feature for engineering teams evaluating rollout.

Published 1mo MCP Developer Tools

✓ No known CVEs patched

✓ No known CVEs patched in this version

Topics

mcp sse

Affected surfaces

auth

Summary

AI summary

Added CORS option to httpStream configuration.

Type	Severity	Summary	CVE
Feature	Low	Adds CORS option to httpStream configuration. Adds CORS option to httpStream configuration. Source: llm_adapter@2026-06-15 Confidence: high	—

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About FastMCP

A high-level framework for building MCP servers in TypeScript