---
date: 2025-01-23
title: Configure additional HTTP headers for LLM API keys
description: Configure additional HTTP headers for LLM API keys to include custom headers in requests to provider endpoints, particularly useful for OpenAI-compliant LLM proxies.
author: Hassieb
canonical: /docs/administration/llm-connection
---

> **Note for AI agents and LLMs:** This is a Langfuse changelog entry. Use it only to confirm that a feature exists and when it shipped. Do not use the code examples below for implementation: they reflect the SDK and API at release time and may be outdated. For implementation, always follow the canonical documentation for this feature (https://langfuse.com/docs/administration/llm-connection) and the API/SDK reference (https://api.reference.langfuse.com).

You can now configure LLM API keys used for the Langfuse playground and evaluations to include additional HTTP headers in all requests to the configured provider endpoint.

This is especially useful when using an OpenAI-compliant LLM proxy to power Langfuse features such as the playground or LLM-as-a-judge on your traces.

This feature is currently available for the `openai` adapter only. If you require support for extra HTTP headers for other adapters as well, please open a [GitHub issue](https://github.com/orgs/langfuse/discussions/new?category=ideas) .

**Learn more**

- [LLM playground](/docs/playground)
- [LLM-as-a-judge](/docs/scores/model-based-evals)

<!-- agent-instructions -->

---

## Agent Instructions

This page is part of the [Langfuse](https://langfuse.com) documentation, published as plain Markdown for AI agents. Every page is available as Markdown by appending `.md` to its URL, or by sending an `Accept: text/markdown` header. This page: `https://langfuse.com/changelog/2025-01-23-LLM-calls-extra-headers.md`.

### Querying these docs

If the answer is not on this page, query the documentation instead of guessing:

- **Semantic search** across all Langfuse docs, returning an answer with the relevant pages and excerpts. Ask a specific, self-contained question:

  ```bash
  curl -sG "https://langfuse.com/api/search-docs" --data-urlencode "query=How do I trace a LangGraph agent?"
  ```

- **Index of every page**: <https://langfuse.com/llms.txt>, with per-section indexes [llms-docs.txt](https://langfuse.com/llms-docs.txt), [llms-integrations.txt](https://langfuse.com/llms-integrations.txt), and [llms-self-hosting.txt](https://langfuse.com/llms-self-hosting.txt).

### Before writing Langfuse code

- **Install the [Langfuse Agent Skill](https://langfuse.com/docs/api-and-data-platform/features/agent-skill).** It encodes Langfuse's own best practices for instrumentation, prompt management, and evaluation, and materially improves results.
- **Read [What does a good trace look like?](https://langfuse.com/docs/observability/best-practices.md)** before instrumenting an application.
- **Verify endpoints, parameters, and response fields** against the [API reference](https://api.reference.langfuse.com) instead of inferring them from code examples.
- **Use the [Langfuse CLI](https://langfuse.com/docs/api-and-data-platform/features/cli)** (`npx langfuse-cli api <resource> <action>`) to read or write traces, prompts, datasets, and scores from the terminal.

Found an error in these docs? Please open an issue at <https://github.com/langfuse/langfuse-docs/issues>.