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-# To use CASSIA
+# CASSIA
 
-plesae 
+CASSIA (Collaborative Agent System for Single cell Interpretable Annotation) is a tool that enhances cell type annotation using multi-agent Large Language Models (LLMs).
 
+- [Refer to the paper for more detail and example]()
+
+## Quick Start
+
+### Installation
+
+```R
+# Install dependencies
 install.packages("devtools")
-and then 
+install.packages("reticulate")
+
+# Install CASSIA
+devtools::install_github("ElliotXie/CASSIA/CASSIA_R")
+```
+
+### Set Up API Keys
+
+- **API Provider Guides:**
+	- [How to get an OpenAI api key](https://platform.openai.com/api-keys)
+	- [How to get an Anthropic api key](https://console.anthropic.com/settings/keys)
+	- [How to get an OpenRouter api key](https://openrouter.ai/settings/keys)
+    - [OpenAI API Documentation](https://beta.openai.com/docs/)
+    - [Anthropic API Documentation](https://docs.anthropic.com/)
+    - [OpenRouter API documentatioon](https://openrouter.ai/docs/quick-start)
+
+
+We recommend starting with OpenRouter as it provides access to most models with a single API key. While slightly more expensive, it offers greater convenience. Direct access via OpenAI or Anthropic provides more stability for production use.
+
+```R
+# For OpenAI
+setLLMApiKey("your_openai_api_key", provider = "openai", persist = TRUE)
+
+# For Anthropic
+setLLMApiKey("your_anthropic_api_key", provider = "anthropic", persist = TRUE)
+
+# For OpenRouter
+setLLMApiKey("your_openrouter_api_key", provider = "openrouter", persist = TRUE)
+```
+
+## Example Data
+
+CASSIA includes example marker data in two formats:
+```R
+# Load example data
+markers_unprocessed <- loadExampleMarkers(processed = FALSE)  # Direct Seurat output
+markers_processed <- loadExampleMarkers(processed = TRUE)     # Processed format
+```
+
+## Pipeline Usage
+
+```R
+runCASSIA_pipeline(
+    output_file_name,     # Base name for output files
+    tissue,               # Tissue type (e.g., "brain")
+    species,              # Species (e.g., "human")
+    marker,               # Marker data from findallmarker
+    max_workers = 4,      # Number of parallel workers
+    annotation_model = "gpt-4o",                    # Model for annotation
+    annotation_provider = "openai",                 # Provider for annotation
+    score_model = "anthropic/claude-3.5-sonnet",    # Model for scoring
+    score_provider = "openrouter",                  # Provider for scoring
+    annotationboost_model="anthropic/claude-3.5-sonnet", #model for annotation boost
+    annotationboost_provider="openrouter", #provider for annotation boost
+    score_threshold = 75,                          # Minimum acceptable score
+    additional_info = NULL                         # Optional context information
+)
+```
+
+## Supported Models
+
+### OpenAI (Most Common)
+- `gpt-4o` (recommended): Balanced performance and cost
+- `gpt-4o-mini`: Faster, more economical option
+- `o1-mini`: Advanced reasoning capabilities (higher cost)
+
+### Anthropic
+- `claude-3-5-sonnet-20241022`: High-performance model
+
+### OpenRouter
+- `anthropic/claude-3.5-sonnet`: High rate limit access to Claude
+- `openai/gpt-4o-2024-11-20`: Alternative access to GPT-4o
+- `meta-llama/llama-3.2-90b-vision-instruct`: Cost-effective open-source option
+
+## Output
+
+The pipeline generates four key files:
+1. Initial annotation results
+2. Quality scores with reasoning
+3. Summary report
+4. Annotation boost report
+
+## Troubleshooting
+
+### Authentication (Error 401)
+```R
+# Check if API key is set correctly
+key <- Sys.getenv("ANTHROPIC_API_KEY")
+print(key)  # Should not be empty
+
+# Reset API key if needed
+setLLMApiKey("your_api_key", provider = "anthropic", persist = TRUE)
+```
+
+### File Errors
+- Use absolute paths when necessary
+- Check file permissions
+- Ensure files aren't open in other programs
+- Verify sufficient disk space
+
+### Best Practices
+- Keep API keys secure
+- Maintain sufficient API credits
+- Backup data before overwriting files
+- Double-check file paths and permissions
 
-devtools::install_github("ElliotXie/CASSIA")
+Note: This README covers basic CASSIA functionality. For a complete tutorial including advanced features and detailed examples, please visit:
+[CASSIA Complete Tutorial](https://cassia-true-final-4.vercel.app/)