Update contribution and setup docs for LLM configuration

CONTRIBUTING.md

@@ -6,8 +6,15 @@ Thank you for your interest in contributing to OpenEvolve! This document provide
 
 1. Fork the repository
 2. Clone your fork: `git clone https://github.com/codelion/openevolve.git`
-3. Install the package in development mode: `pip install -e .`
-4. Run the tests to ensure everything is working: `python -m unittest discover tests`
+3. Install the package in development mode: `pip install -e ".[dev]"`
+4. Set up environment for testing:
+   ```bash
+   # Unit tests don't require a real API key, but the environment variable must be set
+   export OPENAI_API_KEY=test-key-for-unit-tests
+   ```
+5. Run the tests to ensure everything is working: `python -m unittest discover tests`
+
+**Note**: The unit tests do not make actual API calls to OpenAI or any LLM provider. However, the `OPENAI_API_KEY` environment variable must be set to any non-empty value for the tests to run. You can use a placeholder value like `test-key-for-unit-tests`.
 
 ## Development Environment
 
@@ -17,14 +24,32 @@ We recommend using a virtual environment for development:
 python -m venv env
 source env/bin/activate  # On Windows: env\Scripts\activate
 pip install -e ".[dev]"
+
+# For running tests (no actual API calls are made)
+export OPENAI_API_KEY=test-key-for-unit-tests
+
+# For testing with real LLMs during development
+# export OPENAI_API_KEY=your-actual-api-key
 ```
 
+### LLM Configuration for Development
+
+When developing features that interact with LLMs:
+
+1. **Local Development**: Use a mock API key for unit tests
+2. **Integration Testing**: Use your actual API key and configure `api_base` if using alternative providers
+3. **Cost Management**: Consider using cheaper models or [optillm](https://github.com/codelion/optillm) for rate limiting during development
+
 ## Pull Request Process
 
 1. Create a new branch for your feature or bugfix: `git checkout -b feat-your-feature-name`
 2. Make your changes
 3. Add tests for your changes
-4. Run the tests to make sure everything passes: `python -m unittest discover tests`
+4. Run the tests to make sure everything passes:
+   ```bash
+   export OPENAI_API_KEY=test-key-for-unit-tests
+   python -m unittest discover tests
+   ```
 5. Commit your changes: `git commit -m "Add your descriptive commit message"`
 6. Push to your fork: `git push origin feature/your-feature-name`
 7. Submit a pull request to the main repository

README.md

@@ -42,13 +42,41 @@ pip install -e .
 
 ### Quick Start
 
-We use the OpenAI SDK, so you can use any LLM or provider that supports an OpenAI compatible API. Just set the `OPENAI_API_KEY` environment variable
-and update the `api_base` in config.yaml if you are using a provider other than OpenAI. For local models, you can use
-an inference server like [optillm](https://github.com/codelion/optillm).
+#### Setting up LLM Access
+
+OpenEvolve uses the OpenAI SDK, which means it works with any LLM provider that supports an OpenAI-compatible API:
+
+1. **Set the API Key**: Export the `OPENAI_API_KEY` environment variable:
+   ```bash
+   export OPENAI_API_KEY=your-api-key-here
+   ```
+
+2. **Using Alternative LLM Providers**: 
+   - For providers other than OpenAI (e.g., Anthropic, Cohere, local models), update the `api_base` in your config.yaml:
+   ```yaml
+   llm:
+     api_base: "https://your-provider-endpoint.com/v1"
+   ```
+
+3. **Maximum Flexibility with optillm**: 
+   - For advanced routing, rate limiting, or using multiple providers, we recommend [optillm](https://github.com/codelion/optillm)
+   - optillm acts as a proxy that can route requests to different LLMs based on your rules
+   - Simply point `api_base` to your optillm instance:
+   ```yaml
+   llm:
+     api_base: "http://localhost:8000/v1"
+   ```
+
+This setup ensures OpenEvolve can work with any LLM provider - OpenAI, Anthropic, Google, Cohere, local models via Ollama/vLLM, or any OpenAI-compatible endpoint.
 
 ```python
+import os
 from openevolve import OpenEvolve
 
+# Ensure API key is set
+if not os.environ.get("OPENAI_API_KEY"):
+    raise ValueError("Please set OPENAI_API_KEY environment variable")
+
 # Initialize the system
 evolve = OpenEvolve(
     initial_program_path="path/to/initial_program.py",