Windows startup fails with ModuleNotFoundError: No module named 'fcnt…

README.md

@@ -150,6 +150,7 @@ OpenHarness is an open-source Python implementation designed for **researchers,
   <strong>Start here:</strong>
   <a href="#-quick-start">Quick Start</a> ·
   <a href="#-provider-compatibility">Provider Compatibility</a> ·
+  <a href="README_PROVIDERS.md">LLM Providers</a> ·
   <a href="docs/SHOWCASE.md">Showcase</a> ·
   <a href="CONTRIBUTING.md">Contributing</a> ·
   <a href="CHANGELOG.md">Changelog</a>
@@ -242,8 +243,55 @@ oh -p "Fix the bug" --output-format stream-json
 
 ## 🔌 Provider Compatibility
 
+OpenHarness supports a wide variety of LLM providers through its extensible provider registry system. The system automatically detects providers based on API keys, base URLs, and model names.
+
+**📖 [Complete Provider Guide](README_PROVIDERS.md)** | **🚀 [Interactive Demo](scripts/demo_providers.py)**
+
 OpenHarness supports three API formats: **Anthropic** (default), **OpenAI-compatible** (`--api-format openai`), and **GitHub Copilot** (`--api-format copilot`). The OpenAI format covers a wide range of providers.
 
+### Quick Provider Setup
+
+```bash
+# OpenRouter (100+ models)
+export OPENROUTER_API_KEY="sk-or-v1-..."
+oh --model anthropic/claude-3-haiku
+
+# DeepSeek
+export DEEPSEEK_API_KEY="your-key"
+oh --model deepseek-chat
+
+# Groq (fast inference)
+export GROQ_API_KEY="gsk_..."
+oh --model llama3-70b-8192
+
+# Ollama (local)
+oh --base-url http://localhost:11434/v1 --model llama2
+```
+
+### Adding New Providers
+
+To add support for a new LLM provider:
+
+1. Edit `src/openharness/api/registry.py`
+2. Add a `ProviderSpec` to the `PROVIDERS` tuple
+3. Test with `python scripts/demo_providers.py`
+
+Example:
+```python
+ProviderSpec(
+    name="myprovider",
+    keywords=("myprovider", "myai"),
+    env_key="MYPROVIDER_API_KEY",
+    display_name="MyProvider",
+    backend_type="openai_compat",
+    default_base_url="https://api.myprovider.com/v1",
+    detect_by_key_prefix="mp_",  # optional
+    detect_by_base_keyword="myprovider",  # optional
+),
+```
+
+### Anthropic Format (default)
+
 ### Anthropic Format (default)
 
 | Provider profile | Detection signal | Notes |

README_PROVIDERS.md

@@ -0,0 +1,103 @@
+# Adding LLM Providers to OpenHarness
+
+OpenHarness supports a wide variety of LLM providers through its extensible provider registry system. This guide shows you how to add new providers and configure them.
+
+## Quick Start
+
+### For Users: Using Existing Providers
+
+OpenHarness already supports many popular providers. Here's how to use them:
+
+```bash
+# OpenRouter (access to 100+ models)
+export OPENROUTER_API_KEY="sk-or-v1-..."
+oh --model anthropic/claude-3-haiku "Hello world"
+
+# DeepSeek
+export DEEPSEEK_API_KEY="your-key"
+oh --model deepseek-chat "Code review this function"
+
+# Groq (fast inference)
+export GROQ_API_KEY="gsk_..."
+oh --model llama3-70b-8192 "Analyze this code"
+
+# Ollama (local models)
+oh --base-url http://localhost:11434/v1 --model llama2 "Local AI chat"
+```
+
+### For Developers: Adding New Providers
+
+To add a new LLM provider:
+
+1. **Edit the registry** (`src/openharness/api/registry.py`)
+2. **Add your provider spec** to the `PROVIDERS` tuple
+3. **Test the configuration**
+
+Example provider spec:
+```python
+ProviderSpec(
+    name="myprovider",
+    keywords=("myprovider", "myai"),
+    env_key="MYPROVIDER_API_KEY",
+    display_name="MyProvider",
+    backend_type="openai_compat",  # or "anthropic"
+    default_base_url="https://api.myprovider.com/v1",
+    detect_by_key_prefix="mp_",    # optional
+    detect_by_base_keyword="myprovider",  # optional
+    is_gateway=False,
+    is_local=False,
+    is_oauth=False,
+),
+```
+
+## Demo
+
+Run the interactive demo to see how providers work:
+
+```bash
+python scripts/demo_providers.py
+```
+
+This shows:
+- How provider detection works
+- How to add new providers
+- Configuration examples
+- CLI usage patterns
+
+## Supported Providers
+
+OpenHarness currently supports:
+
+- **Anthropic** (Claude models)
+- **OpenAI** (GPT models)
+- **OpenRouter** (100+ models via gateway)
+- **DeepSeek**
+- **Groq** (fast inference)
+- **GitHub Copilot** (OAuth)
+- **Ollama** (local models)
+- And many more...
+
+See `docs/LLM_PROVIDERS.md` for the complete list and detailed configuration instructions.
+
+## Key Concepts
+
+### Provider Detection Priority
+1. API key prefix (e.g., `sk-or-` → OpenRouter)
+2. Base URL keywords (e.g., `deepseek.com` → DeepSeek)
+3. Model name keywords (e.g., `claude` → Anthropic)
+
+### Backend Types
+- `anthropic`: Native Anthropic SDK (best for Claude)
+- `openai_compat`: OpenAI SDK (works with most providers)
+- `copilot`: GitHub Copilot OAuth
+
+### Configuration Methods
+- Environment variables: `export PROVIDER_API_KEY="..."`
+- Command line: `oh --model model-name --base-url https://...`
+- Settings file: `~/.openharness/settings.json`
+
+## Need Help?
+
+- Check the [full documentation](docs/LLM_PROVIDERS.md)
+- Run the demo: `python scripts/demo_providers.py`
+- Test detection: `oh --model your-model-name --dry-run`