langchain-ai/deepagents · error · RuntimeError

No callback URL received (stdin closed). Re-run `dcode mcp l

Error message

No callback URL received (stdin closed). Re-run `dcode mcp login <server>` and paste the URL.

What it means

During OAuth device/authorization-code login, request_callback_url prompts the user on stdin to paste the provider's callback URL. If stdin hits EOF (closed or non-interactive), the library raises this RuntimeError because the OAuth flow cannot complete without the callback URL.

Source

Thrown at libs/code/deepagents_code/mcp_oauth_ui.py:146

    async def request_callback_url(self) -> str:  # noqa: PLR6301
        """Read a trimmed callback URL from stdin via a worker thread.

        Returns:
            The trimmed callback URL string.

        Raises:
            RuntimeError: If stdin is closed before the user replies.
        """
        import asyncio

        try:
            raw = await asyncio.to_thread(input, "Callback URL: ")
        except EOFError as exc:
            msg = (
                "No callback URL received (stdin closed). "
                "Re-run `dcode mcp login <server>` and paste the URL."
            )
            raise RuntimeError(msg) from exc
        return raw.strip()

    async def show_device_code(  # noqa: PLR6301
        self,
        *,
        verification_uri: str,
        user_code: str,
        expires_in: int,
    ) -> None:
        """Print RFC 8628 device-code instructions to stdout."""
        print(  # noqa: T201
            f"\nVisit {verification_uri} and enter code: "
            f"{user_code}\n(code expires in {expires_in}s)\n",
        )

    async def prompt_slack_team_id(self) -> str | None:  # noqa: PLR6301
        """Ask for a Slack team ID via `input()` on a worker thread.

View on GitHub (pinned to a1af029e6e)

Solutions

1. Re-run `dcode mcp login <server>` in an interactive terminal and paste the callback URL when prompted.
2. In Docker/CI, allocate a TTY (`docker run -it`) or pipe the callback URL into stdin: `echo "$URL" | dcode mcp login <server>`.
3. If automation is required, use a flow that does not need a pasted callback (e.g. device-code flow with a verification URI, or pre-provisioned credentials).

Example fix

// before (CI script)
dcode mcp login github
// after
docker run -it ... dcode mcp login github   # or: echo "$CALLBACK_URL" | dcode mcp login github

import sys
if sys.stdin is None or sys.stdin.isatty() is False:
    print("warning: no interactive stdin; callback URL prompt will fail")

try:
    url = await ui.request_callback_url()
except RuntimeError as exc:
    if "stdin closed" in str(exc):
        print("Run interactively or pipe the callback URL: echo $URL | dcode mcp login <server>")
    else:
        raise

When it happens

Trigger: Running `dcode mcp login <server>` with stdin closed or redirected from /dev/null, in CI/non-interactive shells, or after piping input that ends before a URL is supplied.

Common situations: Running the login inside Docker/CI without `-it`; wrapping dcode in a script that consumed stdin; forgetting to allocate a TTY over SSH or in automation.

Related errors

• MCPReauthRequiredError({server_name})
• Authorization denied by provider: {err_code}{detail}
• Callback URL is missing the 'code' parameter.
• Device code request failed: HTTP {response.status_code} from
• Device code response from {device_code_url} is missing requi

AI-assisted analysis of langchain-ai/deepagents@a1af029e6e (2026-08-29). Data as JSON: /api/errors/08930078eb0f8b58. Report an issue: GitHub.