MCP server startup error: JSON Schema Draft 2020-12 not supported #189
Description
With the recent migration to ai sdk v5 and moving from zod v3 to zod v4.
We see that the schema is now draft 2020-12, but based on some documentation I read regarding the mcp spec, it seems the concensus is to have MCP json schema draft to JSON Schema Draft-07
Let me know if this is something we should handle inside fastMCP.
The reason I mention it is because some mcp clients still use the JSON Schema Draft-07 making the latest versions of fastMCP and zod v4 incompatible with some mcp clients like augment code.
Let me know if there is a workaround or if there is a PR to be done about this