diff --git a/src/server/index.ts b/src/server/index.ts
index bcc0e48..e056850 100644
--- a/src/server/index.ts
+++ b/src/server/index.ts
@@ -128,7 +128,7 @@ export type {
   WithoutSystemFields,
   WithOptionalSystemFields,
   SystemIndexes,
-  IndexTiebreakerFields,
+  IndexTiebreakerField,
 } from "./system_fields.js";
 export { httpRouter, HttpRouter, ROUTABLE_HTTP_METHODS } from "./router.js";
 export type { RoutableMethod } from "./router.js";
diff --git a/src/server/schema.test.ts b/src/server/schema.test.ts
index 44d6fbd..2e3c8f3 100644
--- a/src/server/schema.test.ts
+++ b/src/server/schema.test.ts
@@ -432,17 +432,11 @@ describe("DataModelFromSchemaDefinition", () => {
       | "property1"
       | "property2";
     type ExpectedIndexes = {
-      by_property1: ["property1", "_creationTime", "_id"];
-      by_property1_property2: [
-        "property1",
-        "property2",
-        "_creationTime",
-        "_id",
-      ];
+      by_property1: ["property1", "_creationTime"];
+      by_property1_property2: ["property1", "property2", "_creationTime"];
 
-      // System indexes
-      by_creation_time: ["_creationTime", "_id"];
-      by_id: ["_id"];
+      // System index
+      by_creation_time: ["_creationTime"];
     };
     type ExpectedDataModel = {
       table: {
diff --git a/src/server/schema.ts b/src/server/schema.ts
index ae0a680..f7e25e1 100644
--- a/src/server/schema.ts
+++ b/src/server/schema.ts
@@ -38,7 +38,7 @@ import {
 } from "../server/data_model.js";
 import {
   IdField,
-  IndexTiebreakerFields,
+  IndexTiebreakerField,
   SystemFields,
   SystemIndexes,
 } from "../server/system_fields.js";
@@ -200,7 +200,7 @@ export class TableDefinition<
       Indexes &
         Record<
           IndexName,
-          [FirstFieldPath, ...RestFieldPaths, ...IndexTiebreakerFields]
+          [FirstFieldPath, ...RestFieldPaths, IndexTiebreakerField]
         >
     >,
     SearchIndexes,
diff --git a/src/server/system_fields.ts b/src/server/system_fields.ts
index 865531a..2a40175 100644
--- a/src/server/system_fields.ts
+++ b/src/server/system_fields.ts
@@ -46,15 +46,16 @@ export type WithOptionalSystemFields<Document extends GenericDocument> = Expand<
  * @public
  */
 export type SystemIndexes = {
-  // Note `db.get(id)` is simpler and equivalent to a query on `by_id`.
-  // Unless the query is being built dynamically, or doing manual pagination.
-  by_id: ["_id"];
+  // We have a system index `by_id` but developers should never have a use
+  // for querying it (`db.get(id)` is always simpler).
+  // by_id: ["_id"];
 
-  by_creation_time: ["_creationTime", "_id"];
+  by_creation_time: ["_creationTime"];
 };
 
 /**
- * Convex automatically appends "_creationTime" and "_id" to the end of every index to break ties if all other fields are identical.
+ * Convex automatically appends "_creationTime" to the end of every index to
+ * break ties if all of the other fields are identical.
  * @public
  */
-export type IndexTiebreakerFields = ["_creationTime", "_id"];
+export type IndexTiebreakerField = "_creationTime";