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brian austin
brian austin

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Anthropic blocked OpenClaw. ANTHROPIC_BASE_URL still works.

#claudecode #ai #programming #devtools

Anthropic blocked OpenClaw. ANTHROPIC_BASE_URL still works.

If you woke up today to find your Claude Code setup broken because Anthropic cut off OpenClaw subscriptions — you're not alone. As of today, Anthropic is no longer allowing Claude Code subscriptions to route through OpenClaw, and there's an active privilege escalation CVE on top of it.

Here's the good news: ANTHROPIC_BASE_URL still works. And it's Anthropic's own officially documented environment variable.

What happened with OpenClaw

OpenClaw positioned itself as a Claude proxy that let users route Claude Code traffic through an alternative backend. Anthropic has now explicitly blocked Claude Code subscriptions from using it — likely a combination of TOS enforcement and the security vulnerability that was disclosed today.

The CVE is serious: privilege escalation means an attacker could potentially gain elevated access through a compromised OpenClaw endpoint. If you were self-hosting OpenClaw, update your threat model.

The ANTHROPIC_BASE_URL approach is different

Anthropics own Claude Code documentation shows this environment variable:

export ANTHROPIC_BASE_URL=https://your-proxy.example.com
claude
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This isn't a hack. It's in the official docs. Claude Code checks for this variable at startup and routes all API calls through the specified endpoint.

The critical difference from OpenClaw:

  • No TOS gray area — it's a documented feature, not a workaround
  • No CVE — you're not running vulnerable proxy software
  • No maintenance — you're using someone else's endpoint, not self-hosting

What a compliant proxy actually needs

For ANTHROPIC_BASE_URL to work, the endpoint needs to:

  1. Accept the same request format Claude's API expects
  2. Pass your Claude API key through (or use its own valid key)
  3. Return responses in the same format Claude returns them
  4. Handle streaming correctly for real-time output

That's it. No custom protocol. No proprietary format. Just a valid API endpoint.

Setting it up in 30 seconds 

# Option 1: One-time export
export ANTHROPIC_BASE_URL=https://api.simplylouie.com
claude

# Option 2: Permanent in your shell config
echo 'export ANTHROPIC_BASE_URL=https://api.simplylouie.com' >> ~/.zshrc
source ~/.zshrc
claude

# Option 3: Per-session in .env (if using dotenv)
ANTHROPIC_BASE_URL=https://api.simplylouie.com
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Verify it's working:

claude --version  # should show your normal version
claude "hello"    # if it responds, the proxy is routing correctly
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What about rate limits?

This is where proxy routing actually helps most people. Anthropic applies rate limits per API key. If you're hitting limits mid-session on Claude Code, it's because your personal key has hit its tier ceiling.

A shared proxy can spread load across multiple keys — so you see significantly fewer rate limit interruptions during long coding sessions.

# Before proxy: hit rate limit after 45 min of Claude Code
Error: 529 - Overloaded. Please try again.

# After ANTHROPIC_BASE_URL: session continues
# (proxy routes to available capacity)
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The OpenClaw lesson

OpenClaw tried to build a business on top of Claude Code's traffic with a custom protocol and self-hosted infrastructure. That created three risks simultaneously:

  1. TOS risk — Anthropic can (and did) block it
  2. Security risk — self-hosted proxy software becomes an attack surface
  3. Maintenance risk — you're dependent on someone else maintaining complex proxy software

The simpler approach: use the env var Anthropic documented, point it at a compliant endpoint, move on.

Quick comparison

OpenClaw ANTHROPIC_BASE_URL proxy
Anthropic-approved ❌ (now blocked) ✅ (documented feature)
CVE ✅ CVE-2026-33579 ❌ No CVEs
Self-hosted Required Optional
Works today ❌ ✅
Cost Variable ✌️$2/month

Get back to coding

If your Claude Code session broke today, you can be back up in 30 seconds:

export ANTHROPIC_BASE_URL=https://api.simplylouie.com
claude
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SimplyLouie is $2/month. No rate limits on your side. No CVEs. No TOS gray areas. 50% of revenue goes to animal rescue.

Anthropics own env var. Their own documented feature. Still works.

Have questions about migrating from OpenClaw? Drop them in the comments — I'll answer each one.

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