[BUG] Clay MCP sign-in on Windows coincides with account-wide Claude authentication failure

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Summary

Following a Clay MCP authentication attempt inside Claude Code on native Windows, my existing paid Claude Max account became unable to establish any new desktop or browser sessions while existing authenticated sessions remained functional.

On July 31, 2026 PT, during a Clay Agent Plugin MCP sign-in inside Claude Code on native Windows, authentication failed for my existing, active Claude Max account.

Immediately afterward, no new sessions could be established through Claude Code, Claude Desktop, or claude.ai. The issue reproduces across multiple browsers, multiple Windows environments, and a separate macOS system.

One key diagnostic is that the Anthropic Console (platform.claude.com) continues to authenticate successfully with the same email, while my existing Claude mobile session also remains fully functional. Only new Claude.ai, Claude Desktop, and Claude Code sessions fail.

The available evidence suggests the account itself remains valid while new session creation consistently fails.

---

Trigger Sequence

1. Claude Code 2.1.220 running on native Windows (not WSL).
2. Higgsfield MCP authenticated successfully.
3. Installed clay@clay-plugins v2.1.22 at user scope.
4. During the Clay MCP setup, I was prompted to authenticate.
5. At that moment Claude authentication failed.
6. Clay MCP returned error -32000.
7. Claude Code briefly displayed:

"Welcome back jody"

followed immediately by

"Login expired. Please run /login."

---

Current Claude Code Authentication State

{
"loggedIn": false,
"authMethod": "none",
"apiProvider": "firstParty"
}
This state persists after repeated OAuth login attempts.

claude doctor reports no installation problems.

---

Current Behavior

Working

• Anthropic Console (platform.claude.com)

• Existing Claude Max mobile session

Failing

• Claude Code

• Claude Desktop

• claude.ai

• OAuth login

• New desktop/browser session creation

Every attempt to authenticate through Claude Code, Claude Desktop, or claude.ai routes the existing verified email to:

"Let's create your account."

instead of resolving to the existing paid Claude Max account.

---

Troubleshooting Already Performed

• Disabled the Clay plugin.

• Restarted Windows.

• Cleared browser data.

• Tested Chrome, Edge, Incognito, and a separate browser profile.

• Reproduced on a separate Mac.

• Verified system clock.

• Executed:

claude auth logout

followed by

claude auth login

• Confirmed the following environment variables are absent at the process, user, and machine scope:

ANTHROPIC_API_KEY

ANTHROPIC_AUTH_TOKEN

ANTHROPIC_BASE_URL

CLAUDE_CODE_OAUTH_TOKEN

CLAUDE_CONFIG_DIR

---

Observations

I cannot determine whether the Clay plugin caused the authentication failure or merely coincided with it.

The reproducible observation is that the authentication failure began immediately following the Clay MCP sign-in flow and has persisted across multiple browsers, operating systems, and devices.

Support has confirmed the case has been escalated.

Requesting engineering investigation into the interaction between:

• Claude Code authentication

• MCP/plugin authentication

• OAuth session creation

• Account and organization resolution during authentication.

Request

Please investigate whether the authentication state established during the Clay MCP sign-in flow could have affected subsequent OAuth session creation or account/organization resolution for this account.

I am requesting restoration of the existing authentication state and associated account mapping rather than creation of a new account, duplicate account, account merge, or account recreation.

What Should Happen?

A third-party MCP authentication flow should be fully isolated from Claude account authentication and session state.

If plugin authentication fails because the plugin, platform, or MCP implementation is unsupported, that failure should remain isolated to the plugin and should not invalidate existing Claude authentication or affect future session creation.

After the failed MCP authentication attempt:

• Claude Code should either remain authenticated or prompt for a normal OAuth login.

• OAuth should resolve the verified email to the existing Claude Max account.

• Existing account identity and organization membership should remain unchanged.

• Claude.ai, Claude Desktop, and Claude Code should all establish new sessions normally.

A plugin failure should never redirect an existing paid account into new-account onboarding or leave desktop clients unable to establish new authenticated sessions.

Error Messages/Logs

Observed Diagnostics

Clay MCP

Error:

-32000

Claude Code Messages

"Welcome back jody"

"Login expired. Please run /login."

Claude Code Authentication State

{
  "loggedIn": false,
  "authMethod": "none",
  "apiProvider": "firstParty"
}

System Verification

• Claude Code version: 2.1.220

• Native Windows installation (not WSL)

• `claude doctor` reports no installation problems.

Environment Verification

The following environment variables were verified absent at the process, user, and machine scope:

ANTHROPIC_API_KEY

ANTHROPIC_AUTH_TOKEN

ANTHROPIC_BASE_URL

CLAUDE_CODE_OAUTH_TOKEN

CLAUDE_CONFIG_DIR

These checks rule out stale API credentials, overridden authentication tokens, custom API endpoints, or local Claude Code configuration as the source of the authentication failure.

These verification steps rule out stale API credentials, overridden authentication tokens, custom API endpoints, or local Claude Code configuration as likely causes of the observed authentication behavior.

Steps to Reproduce

Environment

• Existing active Claude Max account

• Claude Code 2.1.220

• Native Windows (not WSL)

Observed Sequence

1. Launch Claude Code while authenticated.

1. Install clay@clay-plugins v2.1.22.

1. Configure the plugin.

1. Initiate the Clay MCP authentication flow.

1. Observe Clay MCP returning error -32000.

1. Observe Claude Code briefly displaying "Welcome back jody" followed immediately by "Login expired. Please run /login."

1. Execute claude auth logout.

1. Execute claude auth login.

1. Complete OAuth.

1. Observe the verified email being routed to "Let's create your account."

1. Attempt authentication through Claude Desktop or claude.ai.

1. Observe identical behavior.

1. Repeat from another machine (Windows and macOS tested).

Note

This sequence documents the conditions under which the issue occurred. I cannot confirm that the initial trigger is deterministically reproducible, but once the failure occurred, the authentication behavior reproduced consistently across multiple browsers, devices, and operating systems.

Note

This sequence documents the conditions under which the incident occurred.

I cannot confirm that the initial trigger is deterministically reproducible because it may depend on backend account state or organization resolution. However, once the failure occurred, the authentication behavior reproduced consistently across multiple browsers, operating systems, and devices.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.219 or earlier (exact version unknown)

Claude Code Version

2.1.220

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Business Impact

• Paid Claude Max subscription currently unusable on desktop platforms.
• Development workflow blocked.
• Existing data cannot currently be exported because export requires web/Desktop authentication.
• Existing authenticated mobile session is the only remaining access to conversations and projects.

Support Status

• Human support case is open.

• Case has been escalated.

• No engineering response after five days.

Impact

• Claude Code unusable.

• Claude Desktop unusable.

• claude.ai unusable.

• Existing mobile session remains functional.

• Anthropic Console remains functional.

• Existing conversations cannot currently be exported because export requires web/Desktop authentication.

Observed Evidence

Working

✓ Anthropic Console

✓ Existing mobile session

Failing

✗ Claude Code

✗ Claude Desktop

✗ claude.ai

✗ OAuth session creation

Timeline

Before July 31, 2026

• Claude authentication functioning normally.

July 31, 2026

• Clay MCP requested authentication.

• Clay MCP returned error -32000.

• Claude Code authentication expired.

Immediately afterward

• Claude.ai

• Claude Desktop

• Claude Code

all began routing the existing verified email to:

"Let's create your account."

Current Status

• Existing mobile session remains authenticated.

• Anthropic Console continues to authenticate normally.

• New desktop and browser sessions continue to fail.

The attached diagnostics indicate that the account itself remains valid while new session creation consistently fails across multiple clients and operating systems.

Assessment

The collected evidence indicates that the underlying account remains valid while new OAuth session creation consistently fails across Claude Code, Claude Desktop, and claude.ai.

Because the issue reproduces across multiple operating systems, browsers, and devices while the Anthropic Console and an existing mobile session continue to function normally, the observed behavior appears more consistent with account/session resolution during authentication than with a local installation, browser, plugin, or operating system issue.