platform

mcp/schema.go

@@ -0,0 +1,55 @@
+package mcp
+
+import "encoding/json"
+
+// Tiny JSON-Schema builders for tool input schemas. They keep tool definitions
+// readable without a schema dependency.
+
+// Props is a set of named property schemas for Object.
+type Props map[string]json.RawMessage
+
+// Object builds an object JSON Schema from named property schemas and the list
+// of required keys. required may be nil.
+func Object(p Props, required []string) json.RawMessage {
+	schema := map[string]any{"type": "object"}
+	if len(p) > 0 {
+		schema["properties"] = p
+	} else {
+		schema["properties"] = map[string]any{}
+	}
+	if len(required) > 0 {
+		schema["required"] = required
+	}
+	b, _ := json.Marshal(schema)
+	return b
+}
+
+// Scalar builds a single-typed schema with a description (e.g. Scalar("integer", …)).
+func Scalar(typ, desc string) json.RawMessage {
+	b, _ := json.Marshal(map[string]string{"type": typ, "description": desc})
+	return b
+}
+
+func String(desc string) json.RawMessage  { return Scalar("string", desc) }
+func Integer(desc string) json.RawMessage { return Scalar("integer", desc) }
+func Number(desc string) json.RawMessage  { return Scalar("number", desc) }
+func Bool(desc string) json.RawMessage    { return Scalar("boolean", desc) }
+func ObjectValue(desc string) json.RawMessage {
+	return Scalar("object", desc)
+}
+
+// StringArray builds an array-of-strings schema.
+func StringArray(desc string) json.RawMessage {
+	b, _ := json.Marshal(map[string]any{
+		"type": "array", "description": desc, "items": map[string]string{"type": "string"},
+	})
+	return b
+}
+
+// ObjectArray builds an array-of-objects schema.
+func ObjectArray(desc string) json.RawMessage {
+	b, _ := json.Marshal(map[string]any{
+		"type": "array", "description": desc, "items": map[string]string{"type": "object"},
+	})
+	return b
+}