chore: skip custom json schema generation

Author: dclark27

src/server/mcp.ts

@@ -46,155 +46,6 @@ import { UriTemplate, Variables } from "../shared/uriTemplate.js";
 import { RequestHandlerExtra } from "../shared/protocol.js";
 import { Transport } from "../shared/transport.js";
 
-// Minimal JSON Schema generation for Zod v4
-type JsonSchema = {
-  type: "object" | "string" | "number" | "boolean" | "integer";
-  properties?: Record<string, JsonSchema | { enum: string[]; type?: "string" }>;
-  required?: string[];
-  enum?: string[];
-};
-
-function zodToJsonSchema(schema: ZodObject<ZodRawShape>): JsonSchema {
-  const shape = schema.shape;
-  const properties: NonNullable<JsonSchema["properties"]> = {};
-  const required: string[] = [];
-
-  for (const [key, value] of Object.entries(shape)) {
-    const [unwrapped, isOptional] = unwrapOptional(value as ZodType);
-    const propSchema = toJsonForAny(unwrapped);
-    if (propSchema) {
-      properties[key] = propSchema;
-    } else {
-      // Fallback to empty object schema for unsupported types
-      properties[key] = {} as unknown as JsonSchema;
-    }
-    if (!isOptional) required.push(key);
-  }
-
-  const result: JsonSchema = { type: "object", properties };
-  if (required.length > 0) result.required = required;
-  return result;
-}
-
-function unwrapOptional(s: ZodType): [ZodType, boolean] {
-  // Zod v4 Optional has unwrap(); fall back to heuristic if unavailable
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const anySchema = s as any;
-  if (typeof anySchema.isOptional === "function" && anySchema.isOptional()) {
-    if (typeof anySchema.unwrap === "function") {
-      return [anySchema.unwrap(), true];
-    }
-    // Best-effort: try _def.innerType if present
-    if (anySchema._def?.innerType) {
-      return [anySchema._def.innerType as ZodType, true];
-    }
-    return [s, true];
-  }
-  return [s, false];
-}
-
-function toJsonForAny(
-  s: ZodType,
-): JsonSchema | { enum: string[]; type?: "string" } | undefined {
-  // Prefer Zod v4 built-in conversion when available, then normalize
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const anySchema = s as any;
-  if (typeof anySchema.toJsonSchema === "function") {
-    try {
-      const js = anySchema.toJsonSchema();
-      const normalized = normalizeJsonFragment(js);
-      if (normalized) return normalized;
-    } catch {
-      // fall through to manual mapping
-    }
-  }
-
-  // Manual mapping for common primitives and objects
-  if (isInstanceOf(anySchema, z.ZodString)) return { type: "string" };
-  if (isInstanceOf(anySchema, z.ZodBoolean)) return { type: "boolean" };
-  if (isInstanceOf(anySchema, z.ZodNumber)) return { type: "number" };
-  if (isInstanceOf(anySchema, z.ZodObject))
-    return zodToJsonSchema(anySchema as ZodObject<ZodRawShape>);
-  // Enums
-  if (isInstanceOf(anySchema, z.ZodEnum)) {
-    const values = extractEnumValues(anySchema);
-    if (values) return { type: "string", enum: values };
-  }
-  return undefined;
-}
-
-function extractEnumValues(s: unknown): string[] | undefined {
-  // Try well-known locations across Zod versions
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const anySchema = s as any;
-  if (Array.isArray(anySchema.options)) return anySchema.options as string[];
-  if (Array.isArray(anySchema.values)) return anySchema.values as string[];
-  if (Array.isArray(anySchema._def?.values))
-    return anySchema._def.values as string[];
-  return undefined;
-}
-
-// Avoid `any` in constructor typing for linter compliance
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
-function isInstanceOf<T>(
-  value: unknown,
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  ctor: new (...args: any[]) => T,
-): value is T {
-  // Avoid crashes across dual bundles by checking name and prototype
-  return (
-    typeof value === "object" &&
-    value !== null &&
-    (value as object) instanceof ctor
-  );
-}
-
-function normalizeJsonFragment(
-  js: unknown,
-): JsonSchema | { enum: string[]; type?: "string" } | undefined {
-  if (!js || typeof js !== "object") return undefined;
-  // If this already looks like a primitive schema
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const frag = js as any;
-  if (
-    frag.type === "string" ||
-    frag.type === "number" ||
-    frag.type === "boolean" ||
-    frag.type === "integer"
-  ) {
-    const res: JsonSchema = { type: frag.type };
-    if (Array.isArray(frag.enum)) res.enum = frag.enum;
-    return res;
-  }
-  if (Array.isArray(frag.enum)) {
-    return {
-      type: typeof frag.type === "string" ? frag.type : "string",
-      enum: frag.enum,
-    };
-  }
-  if (
-    frag.type === "object" &&
-    frag.properties &&
-    typeof frag.properties === "object"
-  ) {
-    const properties: Record<
-      string,
-      JsonSchema | { enum: string[]; type?: "string" }
-    > = {};
-    for (const [k, v] of Object.entries(
-      frag.properties as Record<string, unknown>,
-    )) {
-      const nv = normalizeJsonFragment(v);
-      if (nv) properties[k] = nv;
-      else properties[k] = {} as unknown as JsonSchema;
-    }
-    const out: JsonSchema = { type: "object", properties };
-    if (Array.isArray(frag.required) && frag.required.length > 0)
-      out.required = frag.required.slice();
-    return out;
-  }
-  return undefined;
-}
 
 /**
  * High-level MCP server that provides a simpler API for working with resources, tools, and prompts.
@@ -265,13 +116,13 @@ export class McpServer {
               title: tool.title,
               description: tool.description,
               inputSchema: tool.inputSchema
-                ? (zodToJsonSchema(tool.inputSchema) as Tool["inputSchema"])
+                ? z.toJSONSchema(tool.inputSchema) as Tool["inputSchema"]
                 : EMPTY_OBJECT_JSON_SCHEMA,
               annotations: tool.annotations,
             };
 
             if (tool.outputSchema) {
-              toolDefinition.outputSchema = zodToJsonSchema(
+              toolDefinition.outputSchema = z.toJSONSchema(
                 tool.outputSchema,
               ) as Tool["outputSchema"];
             }