[BUG] Atlassian MCP OAuth fails after browser approval in 1.18.25

Description

On 1.18.25, Atlassian MCP OAuth fails after successful browser authorization. The browser reports success, but opencode mcp auth atlassian ends with:

Authentication failed
SSE error: Non-200 status code (202)

Downgrading to 1.18.24 and repeating the same flow succeeds. The behavior appears to be a regression in 1.18.25.

The authorization URL generated by each version is materially different:

• 1.18.25 directs the browser to https://mcp.atlassian.com/v1/authorize.
• 1.18.24 directs the browser to https://auth.atlassian.com/authorize and includes the requested OAuth scopes and resource indicator.

The 1.18.25 browser flow reports authorization success but the CLI then fails with the 202 SSE error. The 1.18.24 flow reports Authentication successful! in the CLI.

Plugins

None

OpenCode version

1.18.25

Steps to reproduce

1. Configure Atlassian as a remote MCP server:

   {
     "mcp": {
       "atlassian": {
         "type": "remote",
         "url": "https://mcp.atlassian.com/v1/mcp/authv2",
         "enabled": true
       }
     }
   }
   

2. Run opencode mcp auth atlassian.

3. Select Yes when asked to re-authenticate.

4. Complete Atlassian authorization in the browser. The browser displays "Authorization successful!"

5. Return to the CLI.

Expected behavior

The CLI should report Authentication successful! and connect the Atlassian MCP server.

Actual behavior

The CLI reports Authentication failed with SSE error: Non-200 status code (202).

Additional confirmation

After downgrading with opencode upgrade 1.18.24, running the exact same configuration and authentication flow succeeds.

Screenshot and/or share link

No response

Operating System

Linux 6.6.87.2-microsoft-standard-WSL2

Terminal

Windows Terminal