> ## Documentation Index
> Fetch the complete documentation index at: https://docs.neuraltrust.ai/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> These docs cover three products: TrustGate (AI agent gateway), TrustGuard (runtime security), and TrustTest (AI red teaming). Start from each product overview for the definition and How it works. Prefer the .md URL next to a page in /llms.txt when you need the full article. Use /llms-full.txt for a single-file dump of the site.

# Models

> Point a provider's own client at the application's LLM plane with the same key, base URL included

If the application also fronts your models, the same key configures the
provider's own client, including the base URL. That is the one value no client
can work out for itself, because the LLM plane lives on a different host from
the MCP one.

<CodeGroup>
  ```python Python theme={null}
  from openai import OpenAI
  from trustgate import TrustGate

  llm = TrustGate().llm()
  openai = OpenAI(base_url=llm.base_url, api_key=llm.api_key)
  ```

  ```ts TypeScript theme={null}
  import OpenAI from "openai"
  import { TrustGate } from "@neuraltrust/trustgate"

  const llm = await new TrustGate().llm()
  const openai = new OpenAI({ baseURL: llm.baseUrl, apiKey: llm.apiKey })
  ```
</CodeGroup>

Nothing is wrapped. The SDK hands over the values and steps aside, so streaming
and every provider option work exactly as the provider's own client implements
them.

## What `llm()` returns

| Field              | Python               | TypeScript         | Use                                                      |
| ------------------ | -------------------- | ------------------ | -------------------------------------------------------- |
| Base URL           | `base_url`           | `baseUrl`          | The OpenAI client. It ends in `/v1`.                     |
| Anthropic base URL | `anthropic_base_url` | `anthropicBaseUrl` | Anthropic's client, which adds `/v1/messages` itself.    |
| API key            | `api_key`            | `apiKey`           | Any provider client's own key parameter.                 |
| Headers            | `headers`            | `headers`          | `X-AG-API-Key`, for a client that takes headers instead. |
| Consumer           | `consumer`           | `consumer`         | The LLM application's slug, for logs and errors.         |

<CodeGroup>
  ```python Python theme={null}
  from anthropic import Anthropic

  claude = Anthropic(base_url=llm.anthropic_base_url, api_key=llm.api_key)
  ```

  ```ts TypeScript theme={null}
  import Anthropic from "@anthropic-ai/sdk"

  const claude = new Anthropic({ baseURL: llm.anthropicBaseUrl, apiKey: llm.apiKey })
  ```
</CodeGroup>

What goes in `model` depends on how the application routes: `"auto"` when it
load-balances, otherwise a model name. See
[What goes in `model`](/trustgate/llm/connect#what-goes-in-model).

## Naming the user

The key identifies the application, not the person using it. To attribute a
model call to one, send `X-NeuralTrust-End-User` with it. The value lands on the
trace and in **Activity**, and grants nothing.

<CodeGroup>
  ```python Python theme={null}
  openai.chat.completions.create(
      model="auto",
      messages=[{"role": "user", "content": "Hello"}],
      extra_headers={"X-NeuralTrust-End-User": "user_123"},
  )
  ```

  ```ts TypeScript theme={null}
  await openai.chat.completions.create(
    { model: "auto", messages: [{ role: "user", content: "Hello" }] },
    { headers: { "X-NeuralTrust-End-User": "user_123" } },
  )
  ```
</CodeGroup>

A key that reaches no LLM application raises
[`PlaneUnavailableError`](/sdks/trustgate/errors). For the gateway side of the
LLM plane, see [Connect your application](/trustgate/llm/connect).