mcp typescript sdk 1.0.3 doesn't validate tool parameter types at runtime

tested the official mcp typescript sdk (version 1.0.3 exactly) and it doesn't do any runtime validation of tool parameters. you declare a tool with a schema that says `count: number` but if the agent sends `count: "five"` as a string, the sdk just deserializes it and passes it straight through to your handler. this crashed our database twice yesterday because the handler assumes it's getting a number and tries to use it in a sql query. the agent (claude sonnet 3.5 via anthropic api) sent malformed json with a string instead of int and our query builder just concatenated it raw. the fix is to add zod validation in every tool handler which is tedious but necessary. the sdk should handle this - if you declare a schema it should validate against it before calling the handler.