diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index ad56a78..95fa24d 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "4.10.0"
+  ".": "4.10.1"
 }
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index a8084fe..bac1746 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,18 @@
 # Changelog
 
+## 4.10.1 (2026-04-09)
+
+Full Changelog: [v4.10.0...v4.10.1](https://github.com/runwayml/sdk-python/compare/v4.10.0...v4.10.1)
+
+### Bug Fixes
+
+* **client:** preserve hardcoded query params when merging with user params ([839c38b](https://github.com/runwayml/sdk-python/commit/839c38bc95d9147b140481907621942c5c503ead))
+
+
+### Chores
+
+* pin GitHub Actions to full commit SHAs ([8f7689b](https://github.com/runwayml/sdk-python/commit/8f7689bac99f57930dd88a9ab3d4c9a279a13888))
+
 ## 4.10.0 (2026-04-01)
 
 Full Changelog: [v4.9.0...v4.10.0](https://github.com/runwayml/sdk-python/compare/v4.9.0...v4.10.0)
diff --git a/pyproject.toml b/pyproject.toml
index dcbf477..ef01d86 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "runwayml"
-version = "4.10.0"
+version = "4.10.1"
 description = "The official Python library for the runwayml API"
 dynamic = ["readme"]
 license = "Apache-2.0"
diff --git a/src/runwayml/_base_client.py b/src/runwayml/_base_client.py
index 5845965..4a464b2 100644
--- a/src/runwayml/_base_client.py
+++ b/src/runwayml/_base_client.py
@@ -540,6 +540,10 @@ def _build_request(
                 files = cast(HttpxRequestFiles, ForceMultipartDict())
 
         prepared_url = self._prepare_url(options.url)
+        # preserve hard-coded query params from the url
+        if params and prepared_url.query:
+            params = {**dict(prepared_url.params.items()), **params}
+            prepared_url = prepared_url.copy_with(raw_path=prepared_url.raw_path.split(b"?", 1)[0])
         if "_" in prepared_url.host:
             # work around https://github.com/encode/httpx/discussions/2880
             kwargs["extensions"] = {"sni_hostname": prepared_url.host.replace("_", "-")}
diff --git a/src/runwayml/_version.py b/src/runwayml/_version.py
index 1f2d85c..ee5b22d 100644
--- a/src/runwayml/_version.py
+++ b/src/runwayml/_version.py
@@ -1,4 +1,4 @@
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
 __title__ = "runwayml"
-__version__ = "4.10.0"  # x-release-please-version
+__version__ = "4.10.1"  # x-release-please-version
diff --git a/tests/test_client.py b/tests/test_client.py
index cff614b..f755671 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -429,6 +429,30 @@ def test_default_query_option(self) -> None:
 
         client.close()
 
+    def test_hardcoded_query_params_in_url(self, client: RunwayML) -> None:
+        request = client._build_request(FinalRequestOptions(method="get", url="/foo?beta=true"))
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true"}
+
+        request = client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/foo?beta=true",
+                params={"limit": "10", "page": "abc"},
+            )
+        )
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true", "limit": "10", "page": "abc"}
+
+        request = client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/files/a%2Fb?beta=true",
+                params={"limit": "10"},
+            )
+        )
+        assert request.url.raw_path == b"/files/a%2Fb?beta=true&limit=10"
+
     def test_request_extra_json(self, client: RunwayML) -> None:
         request = client._build_request(
             FinalRequestOptions(
@@ -1340,6 +1364,30 @@ async def test_default_query_option(self) -> None:
 
         await client.close()
 
+    async def test_hardcoded_query_params_in_url(self, async_client: AsyncRunwayML) -> None:
+        request = async_client._build_request(FinalRequestOptions(method="get", url="/foo?beta=true"))
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true"}
+
+        request = async_client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/foo?beta=true",
+                params={"limit": "10", "page": "abc"},
+            )
+        )
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true", "limit": "10", "page": "abc"}
+
+        request = async_client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/files/a%2Fb?beta=true",
+                params={"limit": "10"},
+            )
+        )
+        assert request.url.raw_path == b"/files/a%2Fb?beta=true&limit=10"
+
     def test_request_extra_json(self, client: RunwayML) -> None:
         request = client._build_request(
             FinalRequestOptions(