Set up coding agents

Beta: The LLM Gateway is in beta.

Configure coding agents to use the standard LLM Gateway endpoint for centralized cost controls, observability, and audit trails. The gateway authenticates each caller, routes by model ID, enforces policies, and traces each call. Claude Code can use the standard Anthropic Messages format, while Codex and Deep Agents Code can use the standard OpenAI-compatible formats. Gemini CLI uses Google’s native API and requires direct model access.

Prerequisites

Your Organization admin has enabled the gateway and completed any required provider setup.
You have a workspace-scoped LangSmith API key with gateway:invoke and workspaces:read permissions.
For bring-your-own-key models, your workspace has the corresponding provider secret. Gateway Credits models do not require a provider secret.

Set your LangSmith API key before configuring a client:

export LANGSMITH_API_KEY="lsv2_..._....cbed3e"

Claude Code CLI

Claude Code supports two separate authentication methods. Choose one before configuring:

Workspace provider secret: The organization manages billing and policies through a provider key stored in workspace secrets. Use this method for org-managed usage.
Claude subscription OAuth: Anthropic bills LLM calls to the user’s personal Claude Plus or Max subscription instead of the workspace provider secret, while LangSmith still enforces gateway permissions, policies, and tracing. Use this method when developers have their own subscriptions.

Use a workspace provider secret

Set ANTHROPIC_API_KEY to your LangSmith API key. Claude Code reads these variables from your shell environment or from the env block in ~/.claude/settings.json. If your LangSmith deployment is on a regional or self-hosted instance, replace the gateway hostname in the examples below with your regional gateway hostname.

Use Anthropic models only

Set ANTHROPIC_BASE_URL to the Anthropic-format gateway endpoint. The gateway infers the anthropic/ provider prefix from the endpoint:

export ANTHROPIC_BASE_URL="https://gateway.smith.langchain.com/anthropic/"
export ANTHROPIC_API_KEY="$LANGSMITH_API_KEY"

claude

Route model tiers across providers

Set ANTHROPIC_BASE_URL to the gateway root, then map each Claude model tier to a provider-prefixed gateway model ID:

export ANTHROPIC_BASE_URL="https://gateway.smith.langchain.com"
export ANTHROPIC_API_KEY="$LANGSMITH_API_KEY"
export ANTHROPIC_DEFAULT_OPUS_MODEL="anthropic/claude-opus-5"
export ANTHROPIC_DEFAULT_SONNET_MODEL="openai/gpt-5.6-terra"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="fireworks/accounts/fireworks/models/glm-5p2"

claude

The model IDs are examples. Map each tier to any model configured in your workspace secrets or available through Gateway Credits; the gateway handles request translation across providers. For details, see API formats.

Use Claude subscription OAuth

Claude subscription OAuth requires an active Claude Code Plus or Max subscription. If you are using a workspace Anthropic API key, use the workspace provider secret method instead.

Claude Code Plus and Max users can send their saved Anthropic OAuth credential through the gateway. This mode does not require an ANTHROPIC_API_KEY in workspace provider secrets. Log in to Claude Code with your subscription, then configure the gateway:

export ANTHROPIC_BASE_URL="https://gateway.smith.langchain.com/anthropic"
export ANTHROPIC_CUSTOM_HEADERS="X-Api-Key: $LANGSMITH_API_KEY"

claude

Treat the ANTHROPIC_CUSTOM_HEADERS value as a secret: it embeds your LangSmith API key, so keep it out of shell history, dotfiles, and shared configuration. Claude Code uses and refreshes the OAuth credential from its saved login, including the required OAuth capability in the anthropic-beta header. The LangSmith API key authenticates the gateway request and remains subject to gateway permissions and policies. The gateway forwards the OAuth bearer to Anthropic, so Anthropic bills the call to the user’s Claude subscription instead of the workspace provider secret. To confirm calls route through the gateway, check that traces appear in the gateway tracing project as described in Verify the setup.

Leave ANTHROPIC_AUTH_TOKEN and ANTHROPIC_API_KEY unset for this mode. Either variable takes precedence over the saved subscription login.

Claude Desktop plugins break when the gateway is configured.

Codex CLI

Codex uses the Responses API. Add the following to ~/.codex/config.toml to call the hosted Kimi K3 model with Gateway Credits through the standard endpoint:

model = "moonshotai/kimi-k3"
model_provider = "langsmith-gateway"

[model_providers.langsmith-gateway]
name = "LangSmith Gateway"
base_url = "https://gateway.smith.langchain.com/v1"
env_key = "LANGSMITH_API_KEY"
wire_api = "responses"
supports_websockets = false

Then run:

codex

To use a bring-your-own-key model instead, replace model with its provider-prefixed ID, such as openai/gpt-5.4-mini.

Codex Desktop plugins break when the gateway is configured. The TOML configuration forces authentication through the gateway, so OpenAI no longer handles plugin authentication directly.

Gemini CLI

Gemini CLI sends Google’s native Generate Content requests, which the standard endpoint does not expose. Follow Direct model access to configure the /gemini route, then run:

gemini

Deep Agents Code

Use the OpenAI-compatible client with the standard endpoint, then pass the hosted model slug through the openai integration:

export OPENAI_BASE_URL="https://gateway.smith.langchain.com/v1"
export OPENAI_API_KEY="$LANGSMITH_API_KEY"

dcode --model openai:moonshotai/kimi-k3

To use a bring-your-own-key model, keep the standard base URL and pass a provider-prefixed model after openai:, for example, openai:anthropic/claude-opus-5. For provider-native integrations and model IDs, see Direct model access.

Company-wide deployment

For organizations rolling the gateway out to all developers, distribute the configuration through mobile device management or a shared shell profile. Distribute:

The standard gateway base URL for each client.
A workspace-scoped LangSmith API key per user or team, depending on your policy granularity.
The model IDs approved for each coding agent.
The Codex config.toml if your organization uses Codex.

Provider API keys stay centralized in LangSmith workspace secrets. Gateway Credits models do not require provider API keys.

Verify the setup

After configuring a coding agent, make a test call and confirm that:

The call succeeds and the agent receives a response.
A trace appears in the gateway or gateway-<short_api_key>-<api_key_id> tracing project in your LangSmith workspace.

If the call fails with a 403, check that your API key’s role includes gateway:invoke and workspaces:read. If a bring-your-own-key call fails with a 400 mentioning a missing provider key, ask your organization admin to add the provider’s key to workspace secrets.

Next steps

Gateway Credits: call hosted models without a provider secret.
Direct model access: configure provider-native routes for coding agents that require them.
Spend policies: set cost limits on developer LLM usage.
Traces, Engine, and access control: understand where gateway traces appear.

Connect these docs to Claude, VSCode, and more via MCP for real-time answers.

Edit this page on GitHub or file an issue.

Core capabilities

Administration and governance

Advanced

Prerequisites

Claude Code CLI

Use a workspace provider secret

Use Anthropic models only

Route model tiers across providers

Use Claude subscription OAuth

Codex CLI

Gemini CLI

Deep Agents Code

Company-wide deployment

Verify the setup

Next steps

​Prerequisites

​Claude Code CLI

​Use a workspace provider secret

​Use Anthropic models only

​Route model tiers across providers

​Use Claude subscription OAuth

​Codex CLI

​Gemini CLI

​Deep Agents Code

​Company-wide deployment

​Verify the setup

​Next steps

Prerequisites

Claude Code CLI

Use a workspace provider secret

Use Anthropic models only

Route model tiers across providers

Use Claude subscription OAuth

Codex CLI

Gemini CLI

Deep Agents Code

Company-wide deployment

Verify the setup

Next steps