Agent Ecosystem Testing GitHub ↗

Friction: this note describes roadblocks while refining testing methodology

Anthropic API key

The Claude docs AI assistant didn’t return any results when asked how to obtain an API key to test the web fetch tool.

I don't have information about how to obtain an API key in the available sources. The documentation shows examples using the web fetch tool with an API key, but doesn't explain the process for acquiring one.

Check out these potentially useful sources that might help: Web fetch tool

Would you like me to try to provide a general answer based on my knowledge instead?

Instructions:

  1. Go to console.anthropic.com and sign up and/or log in
  2. Once you’re in, look for “API Keys” in the left sidebar
  3. Click Create Key, give it a name like web-fetch-testing, and copy it immediately - you won’t be able to see it again after you close that dialog
  4. Add key and value to the .env file
  5. Run source .env
  6. Run python claude-api/web_fetch_test.py

The name you give the key in the Claude console and your .env don’t need to match. The name you gave it in the console - "agent-ecosystem-testing-claude-web-fetch" - is just a human-readable label to help you remember what it’s for - it has no effect on how the key works. ANTHROPIC_API_KEY is just the variable name the script uses to look it up on your machine. These labels are two completely separate things: one is Anthropic’s label in their dashboard, the other is your local environment variable name. The script selects the correct secret.

API not available on the free-tier

This API requires a paid credit balance as there isn’t a free tier for API access - which is separate from the free tier on claude.ai. This API is pay-as-you-go, not a subscription. Add a small amount of credits at console.anthropic.com; otherwise you’ll run into the following error:

anthropic.BadRequestError: Error code: 400 - {'type': 'error', 'error': {'type': 'invalid_request_error', 'message': 'Your credit balance is too low to access the Anthropic API. Please go to Plans & Billing to upgrade or purchase credits.'}, 'request_id': 'req_01...'}

Rebuild venv

deactivate
rm -rf venv
/opt/homebrew/bin/python3.14 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
source .env
python claude-api/web_fetch_test.py