Cline is an open-source agent for VS Code that reads your repository, edits files, and runs terminal commands. It is not tied to one provider: point it at your own endpoint and it works exactly as it would against direct Anthropic or OpenAI access.
Step 1. Install the extension
Open the Extensions panel in VS Code, Cmd+Shift+X on Mac or Ctrl+Shift+X on Windows and Linux, search for Cline, and click Install. A new icon appears in the sidebar once it is done, that is where the chat with the agent opens.
Step 2. Get a Claudexia key
Sign up at claudexia.tech and create an API key in the dashboard. The key looks like sk_cdx_.... One key works for both Claude and GPT models, no need to set up a separate key per provider.
Step 3. Configure the provider in Cline
Open Cline's settings through the gear icon at the top of the chat panel. The API Provider field gives you two working paths.
Anthropic with a custom base URL. Pick the Anthropic provider, turn on Use custom base URL, and paste https://api.claudexia.tech. Put your sk_cdx_... in the API Key field. This path keeps the Anthropic format and fits if you plan to work with Claude models.
OpenAI Compatible. Pick this provider if you want to switch between Claude and GPT inside the same extension. The Base URL is https://api.claudexia.tech/v1, the API Key is the same key, and the Model ID field takes whatever model you want, claude-sonnet-4.6 or gpt-4.1.
Step 4. Pick a model
The model dropdown shows the standard Claude lineup if you picked the Anthropic provider, or a free-text field for the model name under OpenAI Compatible. Sonnet is a sensible default for everyday coding work, and you can switch to Opus for genuinely hard refactors right in the same extension without touching the key.
Step 5. Verify it works
Open any project, give the agent something simple like "add a test for this function," and check that it proposes a plan and asks for confirmation before touching files. If a response comes back and Cline can see the project structure, the setup is done.
A quick terminal check to confirm the key on its own, separate from the extension:
curl https://api.claudexia.tech/v1/messages \
-H "x-api-key: sk_cdx_your_key_here" \
-H "anthropic-version: 2023-06-01" \
-H "content-type: application/json" \
-d '{"model":"claude-sonnet-4.6","max_tokens":100,"messages":[{"role":"user","content":"hello"}]}'
Common problems
A 401 almost always means the key was pasted with a stray space or got cut off during copy. Re-check the field in settings by copying the whole key fresh from the dashboard.
If the model just hangs with no error, the usual cause is a wrong base URL: missing /v1 for the OpenAI Compatible provider, or the opposite, adding it where the Anthropic provider does not need it.
If Cline keeps asking for confirmation on every single action and that gets tedious, that is an extension setting, not a provider one: Cline has an auto-approve mode for reads and for commands you consider safe.
In short
Cline is not locked to one provider, so switching to Claudexia is changing two fields in settings: base URL and key. The Anthropic provider keeps the Claude format, OpenAI Compatible gives you GPT access under the same key. If something stops responding, check the key first and whether /v1 is where it should be, that covers nine problems out of ten.