fix: stop agent retrying commit_and_open_pr on 403 permission denied (#1123)

* fix: stop agent retrying commit_and_open_pr on 403 permission denied

Detect 403/permission-denied push failures in commit_and_open_pr and
return a PERMANENT_FAILURE message so the LLM stops retrying. Also add
prompt-level guidance to the COMMIT_PR_SECTION reinforcing this. Add
unit tests covering both the 403 and non-403 push failure paths.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix: stop safety net retrying permanent push failures

Skip the after-agent PR fallback when commit_and_open_pr reports a permanent GitHub push authorization failure, while preserving fallback behavior for recoverable failures.

---------

Co-authored-by: Claude Agent <agent@anthropic.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Johannes du Plessis <johannes@langchain.dev>

agent/middleware/open_pr.py

@@ -36,6 +36,7 @@ from ..utils.github import (
     git_has_uncommitted_changes,
     git_has_unpushed_commits,
     git_push,
+    is_permanent_github_push_failure,
 )
 from ..utils.github_app import get_github_app_installation_token
 from ..utils.github_token import get_github_token
@@ -87,7 +88,11 @@ async def open_pr_if_needed(
             return None
 
         if pr_payload.get("success"):
-            # Tool already handled commit/push/PR creation
+            return None
+
+        error = pr_payload.get("error")
+        if isinstance(error, str) and is_permanent_github_push_failure(error):
+            logger.info("Skipping PR safety net after permanent push failure")
             return None
 
         pr_title = pr_payload.get("title", "feat: Open SWE PR")

agent/prompt.py

@@ -305,6 +305,8 @@ When you have completed your implementation, follow these steps in order:
 
 **IMPORTANT: Never claim a PR was created or updated unless `commit_and_open_pr` returned `success` and a PR link. If it returns "No changes detected" or any error, report that instead.**
 
+**IMPORTANT: If `commit_and_open_pr` returns an error containing "403", "Permission denied", or "PERMANENT_FAILURE", this is a permanent authorization failure — the token does not have write access to the repository. Do NOT retry. Report the error to the user immediately and stop.**
+
 4. **Notify the source** immediately after `commit_and_open_pr` succeeds. Include a brief summary and the PR link:
    - Linear-triggered: use `linear_comment` with an `@mention` of the user who triggered the task
    - Slack-triggered: use `slack_thread_reply`

agent/tools/commit_and_open_pr.py

@@ -24,6 +24,7 @@ from ..utils.github import (
     git_has_uncommitted_changes,
     git_has_unpushed_commits,
     git_push,
+    is_permanent_github_push_failure,
 )
 from ..utils.github_app import get_github_app_installation_token
 from ..utils.github_token import get_github_token
@@ -200,9 +201,20 @@ def commit_and_open_pr(
 
         push_result = git_push(sandbox_backend, repo_dir, target_branch)
         if push_result.exit_code != 0:
+            push_output = push_result.output.strip()
+            if is_permanent_github_push_failure(push_output):
+                return {
+                    "success": False,
+                    "error": (
+                        f"PERMANENT_FAILURE: do not retry. Git push was rejected with a 403 "
+                        f"permission denied error — the token does not have write access to this "
+                        f"repository. Report this to the user and stop. Details: {push_output}"
+                    ),
+                    "pr_url": None,
+                }
             return {
                 "success": False,
-                "error": f"Git push failed: {push_result.output.strip()}",
+                "error": f"Git push failed: {push_output}",
                 "pr_url": None,
             }
 

agent/utils/github.py

@@ -15,6 +15,17 @@ HTTP_CREATED = 201
 HTTP_UNPROCESSABLE_ENTITY = 422
 
 
+def is_permanent_github_push_failure(output: str) -> bool:
+    """Return whether git push output indicates a permanent auth failure."""
+    normalized_output = output.lower()
+    return (
+        "permanent_failure" in normalized_output
+        or "403" in normalized_output
+        or "permission" in normalized_output
+        or "denied" in normalized_output
+    )
+
+
 def _run_git(
     sandbox_backend: SandboxBackendProtocol, repo_dir: str, command: str
 ) -> ExecuteResponse:

tests/test_commit_and_open_pr_403.py

@@ -0,0 +1,128 @@
+"""Tests that commit_and_open_pr returns a PERMANENT_FAILURE message on 403 push errors."""
+
+from unittest.mock import AsyncMock, MagicMock, patch
+
+from deepagents.backends.protocol import ExecuteResponse
+
+
+def _make_push_result(exit_code: int, output: str) -> ExecuteResponse:
+    return ExecuteResponse(output=output, exit_code=exit_code, truncated=False)
+
+
+def _make_config(thread_id: str = "test-thread") -> dict:
+    return {
+        "configurable": {
+            "thread_id": thread_id,
+            "repo": {"owner": "langchain-ai", "name": "docs"},
+        },
+        "metadata": {},
+    }
+
+
+@patch("agent.tools.commit_and_open_pr.get_config")
+@patch("agent.tools.commit_and_open_pr.get_sandbox_backend_sync")
+@patch("agent.tools.commit_and_open_pr.resolve_repo_dir", return_value="/repo/docs")
+@patch("agent.tools.commit_and_open_pr.git_has_uncommitted_changes", return_value=False)
+@patch("agent.tools.commit_and_open_pr.git_fetch_origin")
+@patch("agent.tools.commit_and_open_pr.git_has_unpushed_commits", return_value=True)
+@patch("agent.tools.commit_and_open_pr.git_current_branch", return_value="open-swe/test-thread")
+@patch("agent.tools.commit_and_open_pr.git_checkout_branch", return_value=True)
+@patch("agent.tools.commit_and_open_pr.git_config_user")
+@patch("agent.tools.commit_and_open_pr.git_add_all")
+@patch("agent.tools.commit_and_open_pr.get_github_token", return_value="ghp_token")
+@patch(
+    "agent.tools.commit_and_open_pr.get_github_app_installation_token",
+    new_callable=AsyncMock,
+    return_value="ghs_token",
+)
+@patch("agent.tools.commit_and_open_pr.git_push")
+def test_403_push_returns_permanent_failure(
+    mock_git_push,
+    mock_get_installation_token,
+    mock_get_token,
+    mock_git_add_all,
+    mock_git_config_user,
+    mock_git_checkout_branch,
+    mock_git_current_branch,
+    mock_git_has_unpushed,
+    mock_git_fetch_origin,
+    mock_git_has_uncommitted,
+    mock_resolve_repo_dir,
+    mock_get_sandbox,
+    mock_get_config,
+) -> None:
+    from agent.tools.commit_and_open_pr import commit_and_open_pr
+
+    mock_get_config.return_value = _make_config()
+    mock_get_sandbox.return_value = MagicMock()
+    mock_git_push.return_value = _make_push_result(
+        exit_code=128,
+        output=(
+            "remote: Permission to langchain-ai/docs.git denied to hinthornw.\n"
+            "fatal: unable to access 'https://github.com/langchain-ai/docs/': "
+            "The requested URL returned error: 403"
+        ),
+    )
+
+    result = commit_and_open_pr(
+        title="fix: something", body="## Description\nfoo\n\n## Test Plan\n- [ ] check"
+    )
+
+    assert result["success"] is False
+    assert result["pr_url"] is None
+    error = result["error"]
+    assert "PERMANENT_FAILURE" in error
+    assert "do not retry" in error
+    assert "403" in error
+
+
+@patch("agent.tools.commit_and_open_pr.get_config")
+@patch("agent.tools.commit_and_open_pr.get_sandbox_backend_sync")
+@patch("agent.tools.commit_and_open_pr.resolve_repo_dir", return_value="/repo/docs")
+@patch("agent.tools.commit_and_open_pr.git_has_uncommitted_changes", return_value=False)
+@patch("agent.tools.commit_and_open_pr.git_fetch_origin")
+@patch("agent.tools.commit_and_open_pr.git_has_unpushed_commits", return_value=True)
+@patch("agent.tools.commit_and_open_pr.git_current_branch", return_value="open-swe/test-thread")
+@patch("agent.tools.commit_and_open_pr.git_checkout_branch", return_value=True)
+@patch("agent.tools.commit_and_open_pr.git_config_user")
+@patch("agent.tools.commit_and_open_pr.git_add_all")
+@patch("agent.tools.commit_and_open_pr.get_github_token", return_value="ghp_token")
+@patch(
+    "agent.tools.commit_and_open_pr.get_github_app_installation_token",
+    new_callable=AsyncMock,
+    return_value="ghs_token",
+)
+@patch("agent.tools.commit_and_open_pr.git_push")
+def test_non_403_push_failure_returns_regular_error(
+    mock_git_push,
+    mock_get_installation_token,
+    mock_get_token,
+    mock_git_add_all,
+    mock_git_config_user,
+    mock_git_checkout_branch,
+    mock_git_current_branch,
+    mock_git_has_unpushed,
+    mock_git_fetch_origin,
+    mock_git_has_uncommitted,
+    mock_resolve_repo_dir,
+    mock_get_sandbox,
+    mock_get_config,
+) -> None:
+    from agent.tools.commit_and_open_pr import commit_and_open_pr
+
+    mock_get_config.return_value = _make_config()
+    mock_get_sandbox.return_value = MagicMock()
+    mock_git_push.return_value = _make_push_result(
+        exit_code=1,
+        output="error: failed to push some refs to 'origin'",
+    )
+
+    result = commit_and_open_pr(
+        title="fix: something", body="## Description\nfoo\n\n## Test Plan\n- [ ] check"
+    )
+
+    assert result["success"] is False
+    assert result["pr_url"] is None
+    error = result["error"]
+    assert "PERMANENT_FAILURE" not in error
+    assert error.startswith("Git push failed:")

tests/test_open_pr_middleware.py

@@ -115,6 +115,44 @@ class TestOpenPrIfNeededMiddleware:
 
         assert result is None
 
+    @pytest.mark.asyncio
+    async def test_skips_when_commit_and_open_pr_failed_permanently(self) -> None:
+        payload = {
+            "success": False,
+            "error": (
+                "PERMANENT_FAILURE: do not retry. Git push was rejected with a 403 "
+                "permission denied error."
+            ),
+            "pr_url": None,
+        }
+        state = self._make_state(
+            [
+                ToolMessage(
+                    content=json.dumps(payload),
+                    tool_call_id="1",
+                    name="commit_and_open_pr",
+                )
+            ]
+        )
+
+        with (
+            patch(
+                "agent.middleware.open_pr.get_config",
+                return_value={
+                    "configurable": {
+                        "thread_id": "thread-permanent",
+                        "repo": {"owner": "org", "name": "repo"},
+                    }
+                },
+            ),
+            patch(
+                "agent.middleware.open_pr.get_sandbox_backend", new_callable=AsyncMock
+            ) as mock_sandbox,
+        ):
+            await open_pr_if_needed.aafter_agent(state, self._make_runtime())
+
+        mock_sandbox.assert_not_called()
+
     @pytest.mark.asyncio
     async def test_proceeds_when_commit_and_open_pr_failed_git_push(self) -> None:
         """When success=False due to git push failure, safety net should attempt PR creation."""
@@ -244,7 +282,7 @@ class TestOpenPrIfNeededMiddleware:
         """
         payload = {
             "success": False,
-            "error": "Git push failed: remote rejected (permission denied)",
+            "error": "Git push failed: remote contains work",
             "pr_url": None,
         }
         state = self._make_state(