Connecting Claude Code

Claude Code is Anthropic's agentic CLI assistant. Through NordRouter it runs on a ruble-paid balance: all you need is an API key and two settings.

Ready-made config (recommended)

Open ~/.claude/settings.json (Windows: C:\Users\YOUR_USER\.claude\settings.json; create the file if it doesn't exist) and replace its contents entirely:

{
    "env": {
        "ANTHROPIC_API_KEY": "sk-nr-YOUR-KEY",
        "ANTHROPIC_BASE_URL": "https://nordrouter.com",
        "ANTHROPIC_MODEL": "anthropic/claude-opus-4.8",
        "ANTHROPIC_DEFAULT_OPUS_MODEL": "anthropic/claude-opus-4.8",
        "ANTHROPIC_DEFAULT_SONNET_MODEL": "anthropic/claude-sonnet-4.6",
        "ANTHROPIC_DEFAULT_HAIKU_MODEL": "anthropic/claude-haiku-4.5",
        "ANTHROPIC_SMALL_FAST_MODEL": "anthropic/claude-haiku-4.5",
        "CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC": "1"
    },
    "permissions": {
        "allow": [],
        "deny": []
    }
}

Paste your key from the dashboard into ANTHROPIC_API_KEY and run claude. That's it.

If you previously signed in with an Anthropic account

Run /logout inside Claude Code — otherwise it may keep using the old login instead of your key.

What the settings mean

Variable	Meaning
ANTHROPIC_API_KEY	Your sk-nr-… key
ANTHROPIC_BASE_URL	https://nordrouter.com — no trailing /v1
ANTHROPIC_MODEL	Main model. You can also set anthropic/claude-sonnet-5 or anthropic/claude-fable-5
ANTHROPIC_DEFAULT_*_MODEL	So the /model opus|sonnet|haiku command picks the correct IDs from our catalog
ANTHROPIC_SMALL_FAST_MODEL	Fast background model for Claude Code's utility tasks

Model names in our catalog use the anthropic/ prefix and dots in versions: anthropic/claude-opus-4.8, not claude-opus-4-8. Full list in the model catalog.

Environment-variable alternative

If you'd rather not touch settings.json, the same settings work as environment variables:

macOS / Linux

export ANTHROPIC_BASE_URL=https://nordrouter.com
export ANTHROPIC_API_KEY=sk-nr-YOUR-KEY
export ANTHROPIC_MODEL=anthropic/claude-opus-4.8
claude

Windows (PowerShell)

$env:ANTHROPIC_BASE_URL = "https://nordrouter.com"
$env:ANTHROPIC_API_KEY = "sk-nr-YOUR-KEY"
$env:ANTHROPIC_MODEL = "anthropic/claude-opus-4.8"
claude

Environment variables only apply to the current terminal window — run claude in the same one.

Common errors

Error	Cause	Fix
Missing Bearer API key	The key wasn't picked up: empty ANTHROPIC_API_KEY or an "apiKeyHelper": "echo ''" line in the config	Set the key; delete the apiKeyHelper line
Auth conflict: Both a token … and an API key are set + endless retries	A stale ANTHROPIC_AUTH_TOKEN (from a previous login) overrides your key — the server receives the wrong credential and returns 401	Unset it: $env:ANTHROPIC_AUTH_TOKEN = $null (Windows) / unset ANTHROPIC_AUTH_TOKEN (macOS/Linux); make sure it's not in settings.json
Invalid URL (POST /v1/v1/messages)	/v1 appended to ANTHROPIC_BASE_URL	Remove /v1: it must be exactly https://nordrouter.com
No pricing available for model claude-opus-4-8	Claude Code requests a model by its "bare" ID	Set ANTHROPIC_MODEL and ANTHROPIC_DEFAULT_*_MODEL as in the config above
Invalid or malformed JSON in settings.json	Broken JSON: missing braces/commas or "smart" quotes pasted from a chat	Replace the file contents entirely with the config above
Invalid API key	Typo in the key, or the key was deleted	Check the key in the dashboard

Still stuck — see troubleshooting or message our support on the marketplace where you bought the top-up.