Claude Code

Claude Code is Anthropic's official CLI coding agent. With WRouter you can drive it with one key that also reaches GPT-5.5, Gemini and other non-Claude models.

Prerequisites

Item	Requirement
Claude Code	≥ 1.0.0
Node.js	≥ 18 (only when installing via npm)
WRouter	A working sk- token — see API Token management

Install

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

# Or via npm
npm i -g @anthropic-ai/claude-code

# Verify
claude --version

Configure

Claude Code reads four environment variables:

Variable	Required	Purpose
ANTHROPIC_BASE_URL	✓	WRouter's Anthropic-compatible endpoint
ANTHROPIC_AUTH_TOKEN	✓	WRouter sk- token
ANTHROPIC_MODEL		Default chat model
ANTHROPIC_SMALL_FAST_MODEL		Small/fast secondary model

macOS / Linux (zsh / bash)

Append to ~/.zshrc or ~/.bashrc:

export ANTHROPIC_BASE_URL="https://wrouter.ai"
export ANTHROPIC_AUTH_TOKEN="sk-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
export ANTHROPIC_MODEL="claude-sonnet-4-6"
export ANTHROPIC_SMALL_FAST_MODEL="claude-haiku-4-5"

source ~/.zshrc to apply.

Windows (PowerShell)

[Environment]::SetEnvironmentVariable("ANTHROPIC_BASE_URL", "https://wrouter.ai", "User")
[Environment]::SetEnvironmentVariable("ANTHROPIC_AUTH_TOKEN", "sk-xxxx...", "User")
[Environment]::SetEnvironmentVariable("ANTHROPIC_MODEL", "claude-sonnet-4-6", "User")
[Environment]::SetEnvironmentVariable("ANTHROPIC_SMALL_FAST_MODEL", "claude-haiku-4-5", "User")

Open a new shell for changes to take effect.

Settings file (cross-platform, version-controllable)

Edit ~/.claude/settings.json:

{
  "env": {
    "ANTHROPIC_BASE_URL": "https://wrouter.ai",
    "ANTHROPIC_AUTH_TOKEN": "sk-xxxx...",
    "ANTHROPIC_MODEL": "claude-sonnet-4-6",
    "ANTHROPIC_SMALL_FAST_MODEL": "claude-haiku-4-5"
  }
}

Use ANTHROPIC_AUTH_TOKEN, not ANTHROPIC_API_KEY. The latter is reserved for Anthropic's first-party login flow.

Verify

claude

Run /status:

Model:        claude-sonnet-4-6
Endpoint:     https://wrouter.ai
Status:       ✓ Connected

Smoke test:

> List files in the current directory

Claude Code should call the LS tool and print the directory.

Recommended models

Model	When	Notes
claude-sonnet-4-6	Daily driver	Speed + quality balance, set as ANTHROPIC_MODEL
claude-fable-5	Hardest problems, flagship quality	Anthropic's latest top-tier model
claude-opus-4-8	Heavy refactors, deep reasoning	Higher cost — switch on demand
claude-haiku-4-5	Summaries, naming, completion	Set as ANTHROPIC_SMALL_FAST_MODEL to cut spend
gpt-5.5 / gpt-5.4	Cross-model comparison	/model gpt-5.5 for a one-off switch

In-session switch:

/model claude-opus-4-8
/model gpt-5.5

Advanced: profile isolation

settings.json doesn't support multiple credential sets. Use shell wrappers:

# ~/.zshrc
claude-prod() {
  ANTHROPIC_AUTH_TOKEN="sk-prod-xxx" claude "$@"
}
claude-dev() {
  ANTHROPIC_AUTH_TOKEN="sk-dev-xxx" claude "$@"
}

Troubleshooting

Symptom	Likely cause	Fix
401 Unauthorized	Wrong / disabled / unset token	echo $ANTHROPIC_AUTH_TOKEN to verify
Endpoint: https://api.anthropic.com	Env var didn't take	New shell; check ~/.claude/settings.json isn't overriding
Model not found	Token's group doesn't include that model	Check https://wrouter.ai/models
Long hangs / 502	Upstream throttling / timeout	Switch to claude-haiku-4-5; check console latency
/status shows Disconnected	Network / TLS	Try curl https://wrouter.ai/v1/models -H "Authorization: Bearer $ANTHROPIC_AUTH_TOKEN"

Known limitations

• Claude Code's Plan Mode, Subagents, and Hooks may degrade when you switch to non-Claude models (e.g. gpt-5.5).
• /login is for the first-party Anthropic account only — WRouter users can ignore it.
• Call logs show the raw Anthropic model name, matching what you pass to /model.