Claude Code

Claude Code brings AI-powered coding capabilities directly to your terminal.

Tested on Claude Code versions:

Installing Claude Code

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

For platform-specific instructions, visit https://code.claude.com/docs/en/overview.

Authentication Methods

There are two ways to authenticate Claude Code with FinOps:

ANTHROPIC_AUTH_TOKEN (Recommended)

Set ANTHROPIC_AUTH_TOKEN to your FinOps virtual key. Claude Code sends this token in the Authorization: Bearer header automatically. FinOps recognizes this header and uses the virtual key for routing and authentication.

Why this is recommended: You do not need to log in to an Anthropic account. No Anthropic credentials are required, as FinOps handles everything through the virtual key.

All code snippets below use this method.

ANTHROPIC_CUSTOM_HEADERS (Alternative)

Set ANTHROPIC_CUSTOM_HEADERS to x-bf-vk: your-virtual-key. This passes the virtual key as a custom header instead of the Authorization header.

Caveat: Because the virtual key is sent as a custom header rather than as the bearer token, Claude Code falls back to standard Anthropic account authentication for the Authorization header. This means you still need to log in with an Anthropic account. No credits are needed on the Anthropic account since billing goes through your FinOps virtual key, but the account login is still required.

Configuring Claude Code to work with FinOps

Claude Code supports multiple authentication methods. Choose the one that matches your account type.

1. Update settings.json

Global settings.json is placed in your home folder.

• macOS / Linux / WSL (User Global): ~/.claude/settings.json
• Windows (User Global): %USERPROFILE%\.claude\settings.json
• Project-Specific: .claude/settings.json (located within your individual project's root directory)
• Local Overrides: .claude/settings.local.json (also in the project root, used for personal preferences that aren't shared via Git)

You will need to update the most granular settings.json.

1. Using alias

1. Add following routing rules in FinOps

sonnet-model route

• Keep it a global level and assign priority you want to assign
• Add model condition as model = sonnet-model. This option is not available out of the box - so type this string and select Create sonnet-model
• And add second header condition; to check if the user-agent starts with claude-cli.
• And then you can map this model to any model you want. In the configuration given - we are using vertex/claude-sonnet-4-6.

haiku-model route

• Repeat the above steps by replacing sonnet-model with haiku-model.

2. Update settings.json

"env": {
 "ANTHROPIC_BASE_URL": "{AI_GATEWAY_URL}/anthropic",
 "ANTHROPIC_AUTH_TOKEN": "your-virtual-key",
 "ANTHROPIC_DEFAULT_HAIKU_MODEL": "haiku-model",
 "ANTHROPIC_DEFAULT_SONNET_MODEL": "sonnet-model"
}

2. Using provider-specific model pinning

Anthropic

Update settings.json to pick Anthropic models. For Anthropic models, you don't need to prefix models with provider name.

"env": {
 "ANTHROPIC_BASE_URL": "{AI_GATEWAY_URL}/anthropic",
 "ANTHROPIC_AUTH_TOKEN": "your-virtual-key",
 "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4-6",
 "ANTHROPIC_DEFAULT_SONNET_MODEL": "claude-sonnet-4-6"
}

Bedrock

Update settings.json to pick Anthropic models on Bedrock.

"env": {
 "ANTHROPIC_BASE_URL": "{AI_GATEWAY_URL}/anthropic",
 "ANTHROPIC_AUTH_TOKEN": "your-virtual-key",
 "ANTHROPIC_DEFAULT_HAIKU_MODEL": "bedrock/global.anthropic.claude-haiku-4-6",
 "ANTHROPIC_DEFAULT_SONNET_MODEL": "bedrock/global.anthropic.claude-sonnet-4-6"
}

If you don't pin using CLI - you can pin these in UI. Go to Dashboard > Models > Model Providers > AWS Bedrock > Key. And add deployments

Vertex

Update settings.json to pick Anthropic models on Vertex.

"env": {
 "ANTHROPIC_BASE_URL": "{AI_GATEWAY_URL}/anthropic",
 "ANTHROPIC_AUTH_TOKEN": "your-virtual-key",
 "ANTHROPIC_DEFAULT_HAIKU_MODEL": "vertex/claude-haiku-4-6",
 "ANTHROPIC_DEFAULT_SONNET_MODEL": "vertex/claude-sonnet-4-6"
}

Azure

Update settings.json to pick Anthropic models on Azure.

"env": {
 "ANTHROPIC_BASE_URL": "{AI_GATEWAY_URL}/anthropic",
 "ANTHROPIC_AUTH_TOKEN": "your-virtual-key",
 "ANTHROPIC_DEFAULT_HAIKU_MODEL": "azure/claude-haiku-4-6",
 "ANTHROPIC_DEFAULT_SONNET_MODEL": "azure/claude-sonnet-4-6"
}

Model Configuration

Claude Code uses three model tiers: Sonnet (default), Opus (complex tasks), and Haiku (fast, lightweight). With FinOps, you can override these defaults to use any model from any provider.

Start with a Specific Model:

Launch Claude Code with a specific model using the --model flag:

# Start with Opus
claude --model claude-opus-4-5-20251101

# Start with Haiku for lightweight tasks
claude --model claude-haiku-4-5-20251001

Switching Models Mid-Session

Use the /model command to switch models during an active session:

# Using full model names
/model claude-opus-4-5-20251101 # This will be used from anthropic provider
/model claude-sonnet-4-5-20250929 # This will be used from anthropic provider

# Using different providers dynamically via FinOps
/model vertex/claude-haiku-4-5
/model azure/claude-sonnet-4-5
/model bedrock/claude-sonnet-4-5

Provider Compatibility

Checklist

1. Ensure the model selected is same as you configured in the settings.json.

If this is not the case -

1. Select model using /config
2. Execute /config
3. Search for model
4. Select the correct model

1. Or pass the model using /model <model_name> e.g., /model sonnet-model