diff --git a/README.md b/README.md
index 8e33ef2..84b33c0 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,23 @@ Go package for automated evaluation of academic papers using LLM-based criteria
 go get gitea.r8z.us/stwhite/paperprocessor
 ```
 
+## API Reference
+
+### ProcessFile
+`func ProcessFile(inputPath, outputPath, criteriaPath string, config Config, debug bool) error`
+
+Processes papers from input JSON file and writes results to output JSON file
+
+Parameters:
+- inputPath: Path to input JSON file containing papers array
+- outputPath: Path to write processing results JSON
+- criteriaPath: Path to text file with evaluation criteria
+- config: Configuration settings for API and processing
+- debug: Enable debug logging when true
+
+Returns:
+- error: Processing error or nil if successful
+
 ## Usage
 
 ### Basic Configuration
@@ -37,7 +54,11 @@ err := paperprocessor.ProcessFile(
     "output/results.json",
     "criteria.txt",
     config,
+    true, // debug mode
 )
+if err != nil {
+    log.Fatal("Processing failed:", err)
+}
 ```
 
 ## Input Formats