Anthropic (Claude)

Anthropic builds the Claude model family and provides access via an API. In Kurahi you can authenticate with an API key or a setup-token.

Option A: Anthropic API key

Best for: standard API access and usage-based billing. Create your API key in the Anthropic Console.

CLI setup

kurahi onboard
# choose: Anthropic API key

# or non-interactive
kurahi onboard --anthropic-api-key "$ANTHROPIC_API_KEY"

Config snippet

{
  env: { ANTHROPIC_API_KEY: "sk-ant-..." },
  agents: { defaults: { model: { primary: "anthropic/claude-opus-4-5" } } },
}

Prompt caching (Anthropic API)

Kurahi supports Anthropic’s prompt caching feature. This is API-only; subscription auth does not honor cache settings.

Configuration

Use the cacheRetention parameter in your model config:

Value	Cache Duration	Description
none	No caching	Disable prompt caching
short	5 minutes	Default for API Key auth
long	1 hour	Extended cache (requires beta flag)

{
  agents: {
    defaults: {
      models: {
        "anthropic/claude-opus-4-5": {
          params: { cacheRetention: "long" },
        },
      },
    },
  },
}

Defaults

When using Anthropic API Key authentication, Kurahi automatically applies cacheRetention: "short" (5-minute cache) for all Anthropic models. You can override this by explicitly setting cacheRetention in your config.

Legacy parameter

The older cacheControlTtl parameter is still supported for backwards compatibility:

• "5m" maps to short
• "1h" maps to long

We recommend migrating to the new cacheRetention parameter.

Kurahi includes the extended-cache-ttl-2025-04-11 beta flag for Anthropic API requests; keep it if you override provider headers (see /gateway/configuration).

Option B: Claude setup-token

Best for: using your Claude subscription.

Where to get a setup-token

Setup-tokens are created by the Claude Code CLI, not the Anthropic Console. You can run this on any machine:

claude setup-token

Paste the token into Kurahi (wizard: Anthropic token (paste setup-token)), or run it on the gateway host:

kurahi models auth setup-token --provider anthropic

If you generated the token on a different machine, paste it:

kurahi models auth paste-token --provider anthropic

CLI setup

# Paste a setup-token during onboarding
kurahi onboard --auth-choice setup-token

Config snippet

{
  agents: { defaults: { model: { primary: "anthropic/claude-opus-4-5" } } },
}

Notes

• Generate the setup-token with claude setup-token and paste it, or run kurahi models auth setup-token on the gateway host.
• If you see “OAuth token refresh failed …” on a Claude subscription, re-auth with a setup-token. See /gateway/troubleshooting#oauth-token-refresh-failed-anthropic-claude-subscription.
• Auth details + reuse rules are in /concepts/oauth.

Troubleshooting

401 errors / token suddenly invalid

• Claude subscription auth can expire or be revoked. Re-run claude setup-token and paste it into the gateway host.
• If the Claude CLI login lives on a different machine, use kurahi models auth paste-token --provider anthropic on the gateway host.

No API key found for provider “anthropic”

• Auth is per agent. New agents don’t inherit the main agent’s keys.
• Re-run onboarding for that agent, or paste a setup-token / API key on the gateway host, then verify with kurahi models status.

No credentials found for profile anthropic:default

• Run kurahi models status to see which auth profile is active.
• Re-run onboarding, or paste a setup-token / API key for that profile.

No available auth profile (all in cooldown/unavailable)

• Check kurahi models status --json for auth.unusableProfiles.
• Add another Anthropic profile or wait for cooldown.

More: /gateway/troubleshooting and /help/faq.