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A 401 Unauthorized error means Claude Code’s request was not accepted as authenticated. It can involve an expired or revoked credential, but the error alone does not prove that an OAuth refresh token expired. First identify which authentication method the CLI is using, then check for an unintended ANTHROPIC_API_KEY, a remote login callback problem, or provider-specific credentials.
What a Claude Code 401 means
Anthropic classifies API 401 responses as authentication_error. Its examples include an API key that is malformed, revoked, or expired; the status code does not identify which cause applies to your setup. See Anthropic’s API error reference.
In particular, a message such as “OAuth token has expired” or “Please run /login” is useful diagnostic text, but it does not establish that every 401 is caused by an expired refresh token. The request may be using a different credential source than expected, or it may fail during a login callback rather than during an API request.
Identify the credential source before changing anything
Claude Code may be authenticated through an account login, an API key, or a configured cloud provider. Check the active shell and setup rather than assuming the subscription login is the credential being used.
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- Account login: Check which account is selected and use
/statusto inspect active authentication where applicable. - API key: Check whether
ANTHROPIC_API_KEYis set in the same shell that launches Claude Code. An environment key can take precedence in relevant cases and may send usage through API billing instead of the expected subscription. Anthropic documents this credential confusion in its plan guidance. - Cloud provider or gateway: If your setup uses Bedrock, Vertex, or another configured provider, troubleshoot that provider’s credentials and settings rather than treating the failure as a standard Claude account login.
For the specific case where an organization has disabled API access and an unintended environment key is present, Anthropic’s FAQ recommends unsetting that key and checking /status to confirm the active authentication method: API access disabled for this organization. Apply that advice to the documented case; do not remove a key blindly if your intended setup relies on API authentication.
Use the fix that matches where the request fails
The browser login callback does not complete
On remote SSH sessions, devcontainers, or networks with strict firewall rules, the browser may not be able to complete a localhost callback. Anthropic’s documented manual flow is to copy the URL printed by the terminal, complete sign-in in a browser, then paste the returned code into the terminal. Follow the steps in Claude Code troubleshooting.
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The wrong account or billing path is selected
If you intended to use a Claude subscription but the CLI is using another account or an API key, Anthropic’s plan guidance recommends logging out, updating Claude Code, restarting the terminal, and signing in again to select the intended account. Check for ANTHROPIC_API_KEY as part of that diagnosis; its presence can route usage through API billing instead of the subscription. Use Anthropic’s plan instructions for the account-selection steps.
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The setup uses Bedrock or Vertex
Cloud-provider authentication has its own prerequisites. Anthropic’s troubleshooting guide calls out checking AWS identity and region for Bedrock, and application-default login plus project and region settings for Vertex. Use the provider-specific checks in the official troubleshooting guide rather than resetting an unrelated Claude account login.
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A normal API request returns 401
Confirm the active credential source and whether the credential is valid for that setup. Run claude doctor from a normal shell and retain the exact error text and request ID. Anthropic’s troubleshooting guidance covers these diagnostics; the request ID and error text are useful if you need to contact support.
If login or logout commands also return 401
Some individual GitHub reports describe recovery commands being affected too. Issue #33811 reports that login, logout, and other commands returned errors and is marked closed as a duplicate. Issue #44930 describes a login attempt returning 401 without starting a browser flow. These are user reports, not official confirmation of a universal or currently prevalent defect, and neither establishes a fix that applies to every setup.
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If the documented steps do not work, record your Claude Code version, authentication mode, exact error, and request ID, then contact Anthropic support or use the project’s feedback channel. Do not assume that deleting a local credentials file is a safe general reset: the available official guidance does not establish a universal token-reset command or endorse that remedy.
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| What to compare | What it helps distinguish |
|---|---|
| Credential source: account OAuth, environment API key, or cloud-provider credentials | Whether the CLI is authenticating with the credential you intended to use |
| Environment: local terminal, remote SSH session, or container | Whether a browser callback or localhost networking problem is plausible |
| Failure stage: login callback or API request | Whether to investigate browser-flow completion or the credential used for requests |
| Failure scope: one account/profile or every configured credential path | Whether the evidence points toward account selection or a broader authentication/configuration problem |
This comparison helps narrow the next check without treating the 401 itself as proof of a refresh-token failure.
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