Claude Code CLI

Set up Claude Code to call supported Ship models through Thesean's Anthropic-compatible Messages API.

Prerequisites

Ensure you have Claude Code installed. See the Claude Code quickstart for more options, or use one of the following:

curl -fsSL https://claude.ai/install.sh | bash

Configuration

Choose one of the following configuration methods:

Option 1: Global Configuration

Create or edit ~/.claude/settings.json. This configuration applies to Claude Code in every project:

{
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.thesean.ai",
    "ANTHROPIC_AUTH_TOKEN": "sk-your-thesean-key",
    "ANTHROPIC_MODEL": "ship-like/claude-sonnet-5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "ship-like/claude-haiku-4-5",
    "ANTHROPIC_SMALL_FAST_MODEL": "ship-like/claude-haiku-4-5"
  }
}

Replace sk-your-thesean-key with your key from the Thesean Dashboard.

To use Opus instead, set ANTHROPIC_MODEL to ship-like/claude-opus-4-8 and restart Claude Code. The built-in /model entries use bare model IDs that Thesean does not serve.

Option 2: Shell Environment

Export the values before starting Claude Code:

export ANTHROPIC_BASE_URL="https://api.thesean.ai"
export ANTHROPIC_AUTH_TOKEN="sk-your-thesean-key"
export ANTHROPIC_MODEL="ship-like/claude-sonnet-5"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="ship-like/claude-haiku-4-5"
export ANTHROPIC_SMALL_FAST_MODEL="ship-like/claude-haiku-4-5"
claude

Add the exports to your shell profile if you want new terminal sessions to inherit them.

Option 3: Secret Manager or Rotating Key

Use Claude Code's apiKeyHelper when your key is stored in a secret manager or rotates automatically. The helper command must print only the current key to standard output.

For example, with the 1Password CLI:

{
  "apiKeyHelper": "op read 'op://Private/Thesean API Key/credential'",
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.thesean.ai",
    "ANTHROPIC_MODEL": "ship-like/claude-sonnet-5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "ship-like/claude-haiku-4-5",
    "ANTHROPIC_SMALL_FAST_MODEL": "ship-like/claude-haiku-4-5"
  }
}

Replace the op read command with the equivalent command for your secret manager. Do not also set ANTHROPIC_AUTH_TOKEN; Claude Code uses the helper output as the request credential and refreshes it periodically or after an HTTP 401 response.

Verify Your Setup

Confirm your credential and model with a direct Messages request:

curl https://api.thesean.ai/v1/messages \
  -H "Authorization: Bearer sk-your-thesean-key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "ship-like/claude-sonnet-5",
    "max_tokens": 16,
    "messages": [{"role": "user", "content": "Hello"}]
  }'

After a successful response, fully quit and relaunch Claude Code, then run /status to confirm the base URL and credential source. Claude Code reads these environment settings only when it starts.

Troubleshooting

• Claude Code asks you to log in: Ensure ANTHROPIC_AUTH_TOKEN is available before first-run setup. Global ~/.claude/settings.json is the most reliable location.
• A settings change is not reflected: Restart Claude Code. In particular, confirm ANTHROPIC_MODEL was loaded when the session started.
• apiKeyHelper cannot find a shell variable: Helpers run through /bin/sh and do not load ~/.zshrc or ~/.bashrc. Use a self-contained secret-manager command rather than relying on a shell-profile export.
• A bare Claude model returns 404: Set ANTHROPIC_MODEL to a full Ship model ID such as ship-like/claude-opus-4-8, then restart Claude Code.
• Ship models do not appear in /model: Claude Code's gateway discovery ignores model IDs that do not begin with claude or anthropic, including Thesean's ship-like/ IDs. Choose the model with ANTHROPIC_MODEL instead of selecting a built-in entry from the picker.
• A 1M-context model fails: Thesean supports ship-like/claude-opus-4-8[1m]. Ensure the selected model has the ship-like/ prefix; a bare built-in model ID does not route through Ship.
• A background task or subagent requests an unavailable Haiku model: Set ANTHROPIC_DEFAULT_HAIKU_MODEL to ship-like/claude-haiku-4-5. On older Claude Code versions, also set ANTHROPIC_SMALL_FAST_MODEL to the same value.
• A direct request returns 401: Recheck the key and ensure it is sent as Authorization: Bearer.
• A direct request returns 402: Add credits in the Thesean Dashboard.
• A feature requests an unavailable model: Some Claude Code features select a model tier independently of ANTHROPIC_MODEL. Configure the corresponding ANTHROPIC_DEFAULT_<TIER>_MODEL override with a supported ship-like/ model.