Manual configuration for Claude Code

Route Claude Code through ScaleMax's native Anthropic Messages endpoint without an installer.

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This page is for Claude Code, not Codex. Claude Code uses Anthropic Messages. For Codex's OpenAI Responses provider, use Manual configuration for Codex.

This is the direct, no-npx setup for an existing Claude Code installation. Do not configure it as an OpenAI-compatible provider, and do not add /v1 to ANTHROPIC_BASE_URL.

Choose the URL that matches the key. The two key types are intentionally not interchangeable.

Your ScaleMax key	`ANTHROPIC_BASE_URL`
API-credit key	`https://api.scalemax.pro`
Claude token-pack key	`https://api.scalemax.pro/token`

Connection settings

Protocol: Anthropic Messages
API-credit base URL: https://api.scalemax.pro
Claude token API base URL: https://api.scalemax.pro/token
Authentication: ANTHROPIC_AUTH_TOKEN, which Claude Code sends as Authorization: Bearer. Not ANTHROPIC_API_KEY.
Default model: ANTHROPIC_MODEL. Without it Claude Code asks for its own default model ID, which may not be on your key.
User settings: ~/.claude/settings.json (Windows: %USERPROFILE%\.claude\settings.json)

Configure Claude Code

Set four environment variables, then start claude in the same terminal. Replace YOUR_SCALEMAX_KEY with your key.

bash

export ANTHROPIC_BASE_URL="https://api.scalemax.pro"
export ANTHROPIC_AUTH_TOKEN="YOUR_SCALEMAX_KEY"
export ANTHROPIC_MODEL="claude-opus-5"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="claude-haiku-4-5-20251001"
claude

powershell

$env:ANTHROPIC_BASE_URL = "https://api.scalemax.pro"
$env:ANTHROPIC_AUTH_TOKEN = "YOUR_SCALEMAX_KEY"
$env:ANTHROPIC_MODEL = "claude-opus-5"
$env:ANTHROPIC_DEFAULT_HAIKU_MODEL = "claude-haiku-4-5-20251001"
claude

If the key came from a Claude token pack, change only ANTHROPIC_BASE_URL to https://api.scalemax.pro/token. Do not use the token URL with an API-credit key.

Keep it for every new terminal

bash

# macOS (zsh). On Linux with bash, use ~/.bashrc instead of ~/.zshrc.
cat >> ~/.zshrc <<'EOF'
export ANTHROPIC_BASE_URL="https://api.scalemax.pro"
export ANTHROPIC_AUTH_TOKEN="YOUR_SCALEMAX_KEY"
export ANTHROPIC_MODEL="claude-opus-5"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="claude-haiku-4-5-20251001"
EOF
# Open a new terminal, then run: claude

powershell

setx ANTHROPIC_BASE_URL "https://api.scalemax.pro"
setx ANTHROPIC_AUTH_TOKEN "YOUR_SCALEMAX_KEY"
setx ANTHROPIC_MODEL "claude-opus-5"
setx ANTHROPIC_DEFAULT_HAIKU_MODEL "claude-haiku-4-5-20251001"
# setx does not change this window. Open a new terminal, then run: claude

setx saves each value for terminals you open later, not the one you are in. Open a new terminal before you run claude.

Or put the same values in the env object of ~/.claude/settings.json (Windows: %USERPROFILE%\.claude\settings.json), merging with any settings you already have. This version also adds the optional model-picker entries described below:

json

{
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.scalemax.pro",
    "ANTHROPIC_AUTH_TOKEN": "YOUR_SCALEMAX_KEY",
    "ANTHROPIC_MODEL": "claude-opus-5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4-5-20251001",
    "CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERY": "1",
    "ANTHROPIC_CUSTOM_MODEL_OPTION": "fable-5",
    "ANTHROPIC_CUSTOM_MODEL_OPTION_NAME": "Fable 5",
    "ANTHROPIC_CUSTOM_MODEL_OPTION_DESCRIPTION": "Fable 5 via ScaleMax"
  }
}

CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERY queries $ANTHROPIC_BASE_URL/v1/models at startup and adds its Claude entries to the /model picker. With the Claude token origin, that becomes https://api.scalemax.pro/token/v1/models; do not replace the origin setting with /token/v1. Claude Code intentionally filters discovered IDs to names beginning with claude or anthropic, so the three ANTHROPIC_CUSTOM_MODEL_OPTION* entries in the example explicitly add ScaleMax's public fable-5 ID to the picker. Claude Code refreshes its discovery cache at startup and falls back to the previous cache if a refresh fails. Gateway discovery requires Claude Code 2.1.129 or later.

Older versions of this page and of the web quick start set CLAUDE_CODE_DISABLE_THINKING, which is not a real Claude Code environment variable. Leave it out. (The actual flag is CLAUDE_CODE_DISABLE_ADAPTIVE_THINKING, and it has no effect on the Claude Opus, Claude Sonnet, and Fable models this guide configures.)

The main model is Opus 5. ANTHROPIC_DEFAULT_HAIKU_MODEL sends lightweight background work to Haiku, reducing wait time without changing the model used for the main coding turn. The custom Fable entry is only useful when your key's catalog includes Fable 5; it sends fable-5 to the ScaleMax gateway and does not expose a provider or backend name. Claude Code streams normal responses and uses prompt caching automatically.

Available Claude models

fable-5 (also accepted as claude-fable-5)
claude-haiku-4-5-20251001
claude-haiku-5-5
claude-opus-4-6
claude-opus-4-7
claude-opus-4-8
claude-opus-5
claude-opus-5-5
claude-sonnet-5
claude-sonnet-5-5

Claude ids ending in [1m] are the same model with the full 1M-token context — use either id.

Use an exact model ID. You can change the default ANTHROPIC_MODEL value or switch models from Claude Code with /model fable-5 (or another ID from the authenticated picker). ScaleMax keeps Fable 5’s public identity and handles compatibility automatically.

Verify with a one-token request

Run this in the terminal where you set the variables. It checks the URL, key, and cheapest Claude route before Claude Code loads its agent prompt.

bash

curl -sS "$ANTHROPIC_BASE_URL/v1/messages" \
  -H "Authorization: Bearer $ANTHROPIC_AUTH_TOKEN" \
  -H "anthropic-version: 2023-06-01" \
  -H "content-type: application/json" \
  -d '{
    "model": "claude-haiku-4-5-20251001",
    "max_tokens": 1,
    "messages": [{"role": "user", "content": "K"}]
  }'

powershell

@'
{
  "model": "claude-haiku-4-5-20251001",
  "max_tokens": 1,
  "messages": [{"role": "user", "content": "K"}]
}
'@ | Set-Content -Path body.json

curl.exe -sS "$env:ANTHROPIC_BASE_URL/v1/messages" `
  -H "Authorization: Bearer $env:ANTHROPIC_AUTH_TOKEN" `
  -H "anthropic-version: 2023-06-01" `
  -H "content-type: application/json" `
  --data-binary "@body.json"

A successful response contains a message ID and a content array. Then run one minimal, non-persistent Claude Code turn:

bash

claude -p "Output the single uppercase letter K as your final answer." \
  --model claude-haiku-4-5-20251001 \
  --max-turns 1 \
  --no-session-persistence \
  --output-format json

powershell

claude -p "Output the single uppercase letter K as your final answer." `
  --model claude-haiku-4-5-20251001 `
  --max-turns 1 `
  --no-session-persistence `
  --output-format json

For an interactive check, start claude and run /status. The Anthropic base URL must match the purchased key type—https://api.scalemax.pro for API credit or https://api.scalemax.pro/token for a Claude token pack.

Keep the key out of settings files (what the installer does)

The ScaleMax CLI sets the same base URL and models, but stores the key in its own file and points Claude Code's apiKeyHelper at it, so the raw key is in neither the settings JSON nor your environment. To do the same by hand, first store the key without echoing it:

bash

umask 077
mkdir -p "$HOME/.claude"
printf "ScaleMax API key: "
IFS= read -r -s SCALEMAX_API_KEY
printf "\n"
printf "%s\n" "$SCALEMAX_API_KEY" > "$HOME/.claude/scalemax.key"
unset SCALEMAX_API_KEY
chmod 600 "$HOME/.claude/scalemax.key"

powershell

New-Item -ItemType Directory -Force -Path "$HOME\.claude" | Out-Null
$secret = Read-Host "ScaleMax API key" -AsSecureString
[IO.File]::WriteAllText("$HOME\.claude\scalemax.key", [System.Net.NetworkCredential]::new("", $secret).Password + "`n")
Remove-Variable secret

Then use apiKeyHelper instead of ANTHROPIC_AUTH_TOKEN in settings.json. Remove ANTHROPIC_AUTH_TOKEN from your environment and settings so the two do not compete. On Windows, replace YOU with your user name (the helper needs the full path; echo $HOME in PowerShell shows it):

json

{
  "apiKeyHelper": "cat ~/.claude/scalemax.key",
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.scalemax.pro",
    "ANTHROPIC_MODEL": "claude-opus-5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4-5-20251001",
    "CLAUDE_CODE_API_KEY_HELPER_TTL_MS": "900000"
  }
}

json

{
  "apiKeyHelper": "powershell -NoProfile -Command \"Get-Content -Raw -LiteralPath 'C:\\Users\\YOU\\.claude\\scalemax.key'\"",
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.scalemax.pro",
    "ANTHROPIC_MODEL": "claude-opus-5",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4-5-20251001",
    "CLAUDE_CODE_API_KEY_HELPER_TTL_MS": "900000"
  }
}

Claude Code caches the helper result for 15 minutes and refreshes it after an authentication failure.

Keep the key private

Keep scalemax.key readable only by your user. Never commit it, paste it into support messages, or put a credential in a project-level .claude/settings.json that is tracked by Git.

Automatic configuration

Install the reusable ScaleMax CLI once, then run it directly—no npx is required:

bash

npm install -g scalemax@latest
scalemax

powershell

npm.cmd install -g scalemax@latest
scalemax.cmd

Windows PowerShell blocks npm’s .ps1 launchers by default (“running scripts is disabled on this system”), so these commands use the .cmd launcher: npx.cmd, npm.cmd, scalemax.cmd. In Command Prompt you can leave out .cmd.

Select Claude Code. The CLI detects whether the key uses API credit or a Claude token pack, backs up the existing user settings, keeps the credential file user-only, and verifies the Anthropic Messages route. Run scalemax doctor (Windows PowerShell: scalemax.cmd doctor) afterward for a repeatable health check.

Enable GitHub skills

Model routing and tool installation are separate. To install Anthropic's official skills marketplace and add bounded public-GitHub read permissions to Claude Code, run:

bash

scalemax claude-tools

powershell

scalemax.cmd claude-tools

The command verifies that example-skills@anthropic-agent-skills is enabled. It does not grant unrestricted downloads or a blanket shell permission. Claude Code still asks before any operation outside the narrow public-GitHub permissions.

Claude Desktop is separate

The Claude desktop app does not read Claude Code's settings.json or its environment variables. Configure the app through its third-party inference settings instead. See Claude Desktop.

For the upstream gateway behavior and version requirements, see Claude Code's gateway guide.