[BUG] Native binary installation ignores HTTP_PROXY for API streaming requests (Bun fetch issue ?)

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

Environment

• Platform: Anthropic API (Claude Max)
• Claude Code version: 2.0.70 (native binary)
• Operating System: Linux (Ubuntu-based)
• Terminal: bash
• Feedback ID: 14271541-f781-487e-83f6-07c7c4ba17f9
• Network: Corporate proxy (Fortinet)

Bug Description

The native binary installation of Claude Code fails to connect to Anthropic API when behind a corporate HTTP proxy, while the NPM installation works correctly in the same environment.

Root cause idea: Claude Code uses two different HTTP clients:

1. axios (with https-proxy-agent) for OAuth/authentication → respects HTTP_PROXY ✅
2. Bun's native fetch() for API streaming/messages → ignores HTTP_PROXY ❌

Debug logs confirm axios correctly configures the proxy agent, but the streaming requests fail with FailedToOpenSocket / Connection error.

Error Messages

[ERROR] Error streaming, falling back to non-streaming mode: Connection error.
[ERROR] Error: Connection error.
    at makeRequest (/$bunfs/root/claude:747:4547)

Debug Evidence

With CLAUDE_CODE_DEBUG=1 DEBUG=*, logs show:

2025-12-16T09:53:36.081Z https-proxy-agent Creating new HttpsProxyAgent instance: 'http://proxy.company.com:8080/'
...
proxy: http://proxy.company.com:8080/
connectOpts: { ALPNProtocols: [Array], host: 'proxy.company.com', port: 8080 }

OAuth requests succeed (axios), but streaming fails (Bun fetch).

Steps to Reproduce

1. Set up corporate HTTP proxy environment:

``bash
export HTTP_PROXY=http://proxy.company.com:8080/
export HTTPS_PROXY=http://proxy.company.com:8080/
``

1. Verify proxy works with curl:

``bash
curl -v --proxy $HTTP_PROXY https://api.anthropic.com/v1/messages
# Returns 405 (expected - GET instead of POST) = connection works
``

1. Install Claude Code via native binary:

``bash
curl -fsSL https://claude.ai/install.sh | bash
``

1. Run Claude Code:

``bash
claude
``

1. Send any message → FailedToOpenSocket error

Expected Behavior

Claude Code should route all HTTP/HTTPS requests through the configured proxy, including streaming API requests.

Actual Behavior

• OAuth/authentication requests work (axios respects proxy)
• API streaming requests fail (Bun fetch ignores proxy)
• Error: Connection error / FailedToOpenSocket

Workarounds Attempted (all failed)

| Workaround | Result |
|------------|--------|
| HTTP_PROXY / HTTPS_PROXY env vars | ❌ Ignored by Bun fetch |
| ALL_PROXY env var | ❌ Ignored |
| NODE_EXTRA_CA_CERTS | ❌ Not a TLS issue |
| NPM installation (npm install -g @anthropic-ai/claude-code) | ✅ Works |

Related Issues

• #332
• #1382
• #217

Additional Context

This blocks enterprise adoption where corporate proxies are mandatory. The NPM version works because Node.js properly handles proxy configuration, while the Bun-based native binary does not.

anonymized_logs.txt