diff --git a/server/routes/transforms.ts b/server/routes/transforms.ts
index 22092703d..30ed9d263 100644
--- a/server/routes/transforms.ts
+++ b/server/routes/transforms.ts
@@ -112,9 +112,14 @@ export default function (services: NodeServices, router: IRouter, dataSourceEnab
       validate: {
         params: schema.object({
           index: schema.string({
-            pattern: /^[^A-Z-_"*+/\\|?#<>][^A-Z"*+/\\|?#<>]*$/,
-            minLength: 1,
-            maxLength: 100000,
+            validate: (value) => {
+              const invalidCharactersPattern = /[\s,:\"*+\/\\|?#><]/;
+              if (value !== value.toLowerCase() || value.startsWith("_") || value.startsWith("-") || invalidCharactersPattern.test(value)) {
+                return "Invalid index name.";
+              }
+
+              return undefined;
+            },
           }),
         }),
         query: schema.object({
@@ -123,9 +128,7 @@ export default function (services: NodeServices, router: IRouter, dataSourceEnab
           ...(dataSourceEnabled
             ? {
                 dataSourceId: schema.string({
-                  minLength: 1,
                   maxLength: 100000,
-                  pattern: "^[a-zA-Z0-9_-]+$",
                 }),
               }
             : {}),
@@ -157,9 +160,19 @@ export default function (services: NodeServices, router: IRouter, dataSourceEnab
             enabled_at: schema.maybe(schema.any()),
             description: schema.maybe(schema.string()),
             source_index: schema.string({
-              pattern: /^[^A-Z-_"*+/\\|?#<>][^A-Z"*+/\\|?#<>]*$/,
-              minLength: 1,
-              maxLength: 100000,
+              validate: (value) => {
+                const invalidCharactersPattern = /[\s,:\"*+\/\\|?#><]/;
+                if (
+                  value !== value.toLowerCase() ||
+                  value.startsWith("_") ||
+                  value.startsWith("-") ||
+                  invalidCharactersPattern.test(value)
+                ) {
+                  return "Invalid index name.";
+                }
+
+                return undefined;
+              },
             }),
             data_selection_query: schema.object({
               match_all: schema.object({
@@ -167,9 +180,19 @@ export default function (services: NodeServices, router: IRouter, dataSourceEnab
               }),
             }),
             target_index: schema.string({
-              pattern: /^[^A-Z-_"*+/\\|?#<>][^A-Z"*+/\\|?#<>]*$/,
-              minLength: 1,
-              maxLength: 100000,
+              validate: (value) => {
+                const invalidCharactersPattern = /[\s,:\"*+\/\\|?#><]/;
+                if (
+                  value !== value.toLowerCase() ||
+                  value.startsWith("_") ||
+                  value.startsWith("-") ||
+                  invalidCharactersPattern.test(value)
+                ) {
+                  return "Invalid index name.";
+                }
+
+                return undefined;
+              },
             }),
             page_size: schema.number(),
             groups: schema.arrayOf(
@@ -188,9 +211,7 @@ export default function (services: NodeServices, router: IRouter, dataSourceEnab
           ...(dataSourceEnabled
             ? {
                 dataSourceId: schema.string({
-                  minLength: 1,
                   maxLength: 100000,
-                  pattern: "^[a-zA-Z0-9_-]+$",
                 }),
               }
             : {}),
diff --git a/server/services/TransformService.test.ts b/server/services/TransformService.test.ts
new file mode 100644
index 000000000..7c7208b5f
--- /dev/null
+++ b/server/services/TransformService.test.ts
@@ -0,0 +1,56 @@
+import { schema } from "@osd/config-schema";
+
+describe("Index Name Validation", () => {
+  const validateSchema = schema.object({
+    indexName: schema.string({
+      validate: (value) => {
+        const invalidCharactersPattern = /[\s,:\"*+\/\\|?#><]/;
+        if (value !== value.toLowerCase() || value.startsWith("_") || value.startsWith("-") || invalidCharactersPattern.test(value)) {
+          return "Invalid index name.";
+        }
+
+        return undefined;
+      },
+    }),
+    dataSourceId: schema.maybe(schema.string()),
+  });
+
+  const validateQuery = (indexName: string) => {
+    try {
+      validateSchema.validate({ indexName });
+      return undefined;
+    } catch (e) {
+      return e.message;
+    }
+  };
+
+  it("should fail validation for index names with uppercase letters", () => {
+    const errorMessage = validateQuery("IndexNameWithUppercase");
+    expect(errorMessage).toBe("[indexName]: Invalid index name.");
+  });
+
+  it("should fail validation for index names starting with an underscore", () => {
+    const errorMessage = validateQuery("_indexname");
+    expect(errorMessage).toBe("[indexName]: Invalid index name.");
+  });
+
+  it("should fail validation for index names starting with a hyphen", () => {
+    const errorMessage = validateQuery("-indexname");
+    expect(errorMessage).toBe("[indexName]: Invalid index name.");
+  });
+
+  it("should fail validation for index names containing invalid characters", () => {
+    const errorMessage = validateQuery("********************************");
+    expect(errorMessage).toBe("[indexName]: Invalid index name.");
+  });
+
+  it("should pass validation for valid index names", () => {
+    const errorMessage = validateQuery("valid_index-name123");
+    expect(errorMessage).toBeUndefined();
+  });
+
+  it("should fail validation for index names containing spaces", () => {
+    const errorMessage = validateQuery("invalid index");
+    expect(errorMessage).toBe("[indexName]: Invalid index name.");
+  });
+});