diff --git a/packages/js/api-client/package.json b/packages/js/api-client/package.json
index 403da4f08d3..7c1ea7c943d 100644
--- a/packages/js/api-client/package.json
+++ b/packages/js/api-client/package.json
@@ -49,6 +49,6 @@
     "vitest": "^2.1.4"
   },
   "dependencies": {
-    "openapi-fetch": "^0.11.2"
+    "openapi-fetch": "^0.13.0"
   }
 }
diff --git a/packages/js/api-client/src/auth.ts b/packages/js/api-client/src/auth.ts
index c142dd53698..95b8ccd51af 100644
--- a/packages/js/api-client/src/auth.ts
+++ b/packages/js/api-client/src/auth.ts
@@ -1,4 +1,4 @@
-import type { Middleware } from "openapi-fetch"
+import type { MiddlewareCallbackParams } from "openapi-fetch"
 import type { components } from "./generated/openverse"
 import type { OpenverseClient, ClientCredentials } from "./types"
 
@@ -11,7 +11,15 @@ type OAuth2Token = components["schemas"]["OAuth2Token"]
 const currTimestamp = (): number => Math.floor(Date.now() / 1e3)
 export const EXPIRY_THRESHOLD = 5 // seconds
 
-export class OpenverseAuthMiddleware implements Middleware {
+type MiddlewareOnRequest = (
+  options: MiddlewareCallbackParams
+) => void | Request | undefined | Promise<Request | undefined | void>
+
+interface OpenverseMiddleware {
+  onRequest: MiddlewareOnRequest
+}
+
+export class OpenverseAuthMiddleware implements OpenverseMiddleware {
   /**
    * An Openverse REST API client.
    *
@@ -57,7 +65,10 @@ export class OpenverseAuthMiddleware implements Middleware {
     this.credentials = credentials
   }
 
-  onRequest: Middleware["onRequest"] = async ({ schemaPath, request }) => {
+  onRequest: OpenverseMiddleware["onRequest"] = async ({
+    schemaPath,
+    request,
+  }) => {
     if (schemaPath == "/v1/auth_tokens/token/") {
       // Do not send auth headers for token generation requests
       return request
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 433a708412f..aeb4b0a120a 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -254,8 +254,8 @@ importers:
   packages/js/api-client:
     dependencies:
       openapi-fetch:
-        specifier: ^0.11.2
-        version: 0.11.2
+        specifier: ^0.13.0
+        version: 0.13.3
     devDependencies:
       '@rollup/plugin-typescript':
         specifier: ^12.0.0
@@ -5452,11 +5452,11 @@ packages:
     resolution: {integrity: sha512-7x81NCL719oNbsq/3mh+hVrAWmFuEYUqrq/Iw3kUzH8ReypT9QQ0BLoJS7/G9k6N81XjW4qHWtjWwe/9eLy1EQ==}
     engines: {node: '>=12'}
 
-  openapi-fetch@0.11.2:
-    resolution: {integrity: sha512-zc37VvX9vHJjJxNY3JLhg5Ks3J3KSL56NJrIAp2QRt/fdkOhGQHBTVY+Zz7tEOdqocS/1xfRTzWC6NguCGjUnA==}
+  openapi-fetch@0.13.3:
+    resolution: {integrity: sha512-M1THnPkNOXUPsQKZfqunhW/wqH8l3/W3Vlj4lemQynf4mTaTwBTvL2pgjBe0zerL/GFT5ttCHu9fYvanUI3tOw==}
 
-  openapi-typescript-helpers@0.0.12:
-    resolution: {integrity: sha512-FO+5kTWO6KDutigamr2MRwciYkAUYhqdctlyVRrQOe2uxif2/O2+GcS07jNnP36AUK6ubSsGu3GeBiYIc6eQzA==}
+  openapi-typescript-helpers@0.0.15:
+    resolution: {integrity: sha512-opyTPaunsklCBpTK8JGef6mfPhLSnyy5a0IN9vKtx3+4aExf+KxEqYwIy3hqkedXIB97u357uLMJsOnm3GVjsw==}
 
   openapi-typescript@7.4.3:
     resolution: {integrity: sha512-xTIjMIIOv9kNhsr8JxaC00ucbIY/6ZwuJPJBZMSh5FA2dicZN5uM805DWVJojXdom8YI4AQTavPDPHMx/3g0vQ==}
@@ -13768,11 +13768,11 @@ snapshots:
       is-docker: 2.2.1
       is-wsl: 2.2.0
 
-  openapi-fetch@0.11.2:
+  openapi-fetch@0.13.3:
     dependencies:
-      openapi-typescript-helpers: 0.0.12
+      openapi-typescript-helpers: 0.0.15
 
-  openapi-typescript-helpers@0.0.12: {}
+  openapi-typescript-helpers@0.0.15: {}
 
   openapi-typescript@7.4.3(encoding@0.1.13)(typescript@5.6.3):
     dependencies: