diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 47736a5..a23d2b1 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.1.0-alpha.16"
+  ".": "0.1.0-alpha.17"
 }
diff --git a/.stats.yml b/.stats.yml
index a5829a7..b840065 100644
--- a/.stats.yml
+++ b/.stats.yml
@@ -1,2 +1,2 @@
 configured_endpoints: 31
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/clear-street%2Fstudio-sdk-507601d533175bf3b74a3b04c29d55029c585b24a4ec873bc43d93fe76528076.yml
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/clear-street%2Fstudio-sdk-f04f51a2adbacf75b26ed0b3cd1920c8e2dc63a35c78a579bb8f007247307082.yml
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 719a2c1..04b4f3f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 0.1.0-alpha.17 (2024-12-19)
+
+Full Changelog: [v0.1.0-alpha.16...v0.1.0-alpha.17](https://github.com/clear-street/studio-sdk-node/compare/v0.1.0-alpha.16...v0.1.0-alpha.17)
+
+### Features
+
+* **api:** add average cost to positions ([#78](https://github.com/clear-street/studio-sdk-node/issues/78)) ([10bd7e6](https://github.com/clear-street/studio-sdk-node/commit/10bd7e6221af9757041df1115ffbb60fc591f6b6))
+
 ## 0.1.0-alpha.16 (2024-12-17)
 
 Full Changelog: [v0.1.0-alpha.15...v0.1.0-alpha.16](https://github.com/clear-street/studio-sdk-node/compare/v0.1.0-alpha.15...v0.1.0-alpha.16)
diff --git a/package.json b/package.json
index 4d1d53d..121a595 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@clear-street/studio-sdk",
-  "version": "0.1.0-alpha.16",
+  "version": "0.1.0-alpha.17",
   "description": "The official TypeScript library for the Studio SDK API",
   "author": "Studio SDK <studiosupport@clearstreet.io>",
   "types": "dist/index.d.ts",
diff --git a/src/resources/shared.ts b/src/resources/shared.ts
index 1267101..fcaf094 100644
--- a/src/resources/shared.ts
+++ b/src/resources/shared.ts
@@ -267,19 +267,24 @@ export interface Position {
   /**
    * Account ID for the account.
    */
-  account_id?: string;
+  account_id: string;
 
   /**
    * Account number for the account.
    */
-  account_number?: string;
+  account_number: string;
+
+  /**
+   * The average cost of the position.
+   */
+  average_cost: number;
 
   /**
    * String representation of quantity.
    */
-  quantity?: string;
+  quantity: string;
 
-  symbol?: string;
+  symbol: string;
 }
 
 export interface RegtMarginSimulation {
diff --git a/src/version.ts b/src/version.ts
index baebd9d..35b0d1b 100644
--- a/src/version.ts
+++ b/src/version.ts
@@ -1 +1 @@
-export const VERSION = '0.1.0-alpha.16'; // x-release-please-version
+export const VERSION = '0.1.0-alpha.17'; // x-release-please-version