Fix: No API Key Found for Provider "anthropic"

This error means exactly what it says: OpenClaw looked for an Anthropic API key and found nothing. It usually happens after a fresh install, after switching models, or when the config was reset. The fix takes about 2 minutes.

The Error

The second variant (agent failed before reply) means the agent started, tried to call Claude, and failed at the first LLM request. No response is delivered to your chat channel.

Fix A: Add apiKey to openclaw.json (Most Common)

Open your openclaw.json and make sure the llm section looks like this:

{
  "llm": {
    "provider": "anthropic",
    "apiKey": "sk-ant-YOUR-KEY-HERE",
    "model": "claude-sonnet-4-5"
  }
}

After saving the config, restart the gateway:

openclaw gateway restart

Fix B: Use Environment Variable Instead

If you prefer not to put the key directly in openclaw.json (e.g. the file is in a shared repo), set it as an environment variable:

# Add to your shell profile or .env file
export ANTHROPIC_API_KEY=sk-ant-YOUR-KEY-HERE

# Then start or restart the gateway
openclaw gateway restart

OpenClaw reads ANTHROPIC_API_KEY automatically when no apiKey is set in the config. If both are set, the config value takes precedence.

Fix C: Wrong Provider Name

A common mistake is specifying a Claude model name in the model field while leaving provider as something else (or blank). OpenClaw does not infer the provider from the model name:

"provider": "openai",
"model": "claude-sonnet-4-5"

"provider": "claude",
"model": "claude-sonnet-4-5"

"provider": "anthropic",
"model": "claude-sonnet-4-5"

Fix D: Key Exists But Still Getting the Error

If you can see the key in openclaw.json but the error persists, the gateway may be reading a cached or stale config. Try a full stop and start (not just restart):

openclaw gateway stop
# wait 3 seconds
openclaw gateway start

Also check that you're editing the right file. OpenClaw looks for config at ~/.openclaw/openclaw.json by default. If you edited a different copy, the running gateway won't see it.

openclaw config --path

Don't Have an Anthropic Key?

Get one from the Anthropic console: