Amp

Amp is a coding agent from Sourcegraph; the CLI and the IDE extensions share the same account and settings. Instead of the usual "OpenAI-compatible Base URL" input, you point the entire backend at a custom endpoint via the amp.url setting, with credentials stored separately in a secrets file.

PrerequisitesCopy anchor link

First create a dedicated key for Amp on the console's "API Keys" page (naming it amp-cli makes usage easier to track):

• Console: https://aicentos.com
• Create a key: https://aicentos.com/keys
• Top up when the balance runs out: https://aicentos.com/wallet

Configuration to fill inCopy anchor link

Setup stepsCopy anchor link

All of Amp's settings carry the amp. prefix; the user-level configuration file is located at:

• macOS / Linux: ~/.config/amp/settings.json
• Windows: %USERPROFILE%\.config\amp\settings.json

Create the directories first, then write the backend address:

mkdir -p ~/.config/amp ~/.local/share/amp

{
  "amp.url": "https://aicentos.com/v1"
}

The API Key does not go in this file; it lives in a separate secrets file under the key apiKey@<your URL>:

{
  "apiKey@https://aicentos.com/v1": "sk-your-API-Key"
}

Once the configuration takes effect, amp login is no longer needed and requests go straight to the endpoint you specified. If you previously signed in, run amp logout first and then restart amp to avoid a leftover login state overriding the configuration.

You can also override temporarily with environment variables, which is handy for a one-off verification:

export AMP_URL="https://aicentos.com/v1"
export AMP_API_KEY="sk-your-API-Key"

Note: once these two variables are set, Amp skips the login flow and they take precedence over the configuration file.

TestCopy anchor link

Send a lightweight request first to confirm the endpoint has been switched:

amp -x "Answer in one sentence: what is 1+1?"

A normal response means the configuration is active. If you get a 401, the key in the secrets file most likely does not exactly match amp.url (including whether /v1 is at the end).

NotesCopy anchor link

• Amp's backend protocol is its own management API, not the generic OpenAI-compatible protocol, so amp.url must point at an endpoint that also serves the Anthropic Messages (/v1/messages) style API.
• aicentos offers a native Claude format API (see Native Claude format) and an OpenAI-compatible API (see Chat Completions); Amp uses the former.
• Amp requests fixed model IDs; if the endpoint has no model with that name, it falls back or errors. When that happens, check the model name against the Model Gallery in the console.
• Settings for the IDE extensions (VS Code / Cursor / Windsurf) are maintained separately from the CLI; the Amp URL and Amp API Key need to be filled in there as well.
• A .amp/settings.json in the workspace overrides user-level settings; when troubleshooting, first make sure no such file exists in the current directory.

Related linksCopy anchor link

• Official settings documentation: https://ampcode.com/docs/cli/settings