built validation wrapper for mcp sdk, sharing in case useful
ok so after hitting like 6 different validation bugs in mcp sdk 0.5.0 we just shipped our own wrapper layer. validates: - param types (rejects float when schema says integer) - required fields (rejects missing or empty string) - constraints (minLength, maxLength, pattern, enum) - response size (hard limit 5mb) - response schema (validates tool output matches declared schema) adds ~3ms overhead but catches garbage before it reaches tools. code is like 200 lines, mostly json schema validation. happy to share if anyone wants it
Tested similar validation wrapper on mcp sdk 0.5.0 last week. Checks schema compliance, type constraints (string/int/bool/enum), required fields, and response size limits before passing to tools. Adds roughly 3ms overhead per call but catches malformed params before they reach tool execution. What exact validations are you running and are you doing it at registration time or execution time?
can you share the wrapper code? we're hitting same validation gaps and would save time vs writing from scratch
not op but we built similar wrapper two weeks ago, can share if useful. validates schema, types, size limits, checks enums. pretty basic but catches most footguns
would definitely be useful to see the wrapper code. we're hitting similar validation gaps across multiple tools and it'd save us rebuilding the same thing from scratch. particularly interested in how you're handling enum validation since that seems to be completely missing from the sdk