feat: add --debug flag with levels and centralized logging

CHANGES
- Add --debug flag controlling runtime logging verbosity levels
- Introduce internal/log package with Off, Basic, Detailed, Trace
- Replace ad-hoc Debugf and globals with centralized debug logger
- Wire debug level during early CLI argument parsing
- Add bash, zsh, fish completions for --debug levels
- Document debug levels in README with usage examples
- Add comprehensive STT guide covering models, flags, workflows
- Simplify splitAudioFile signature and log ffmpeg chunking operations
- Remove FABRIC_STT_DEBUG environment variable and related code
- Clean minor code paths in vendors and template modules

README.md

@@ -636,10 +636,20 @@ Application Options:
       --yt-dlp-args=                Additional arguments to pass to yt-dlp (e.g. '--cookies-from-browser brave')
       --thinking=                   Set reasoning/thinking level (e.g., off, low, medium, high, or
                                     numeric tokens for Anthropic or Google Gemini)
+      --debug=                     Set debug level (0: off, 1: basic, 2: detailed, 3: trace)
 Help Options:
   -h, --help                        Show this help message
 ```
 
+### Debug Levels
+
+Use the `--debug` flag to control runtime logging:
+
+- `0`: off (default)
+- `1`: basic debug info
+- `2`: detailed debugging
+- `3`: trace level
+
 ## Our approach to prompting
 
 Fabric _Patterns_ are different than most prompts you'll see.

cmd/generate_changelog/incoming/1718.txt

@@ -0,0 +1,7 @@
+### PR [#1718](https://github.com/danielmiessler/Fabric/pull/1718) by [ksylvan](https://github.com/ksylvan): Implement Configurable Debug Logging Levels
+
+- Add --debug flag controlling runtime logging verbosity levels
+- Introduce internal/log package with Off, Basic, Detailed, Trace
+- Replace ad-hoc Debugf and globals with centralized debug logger
+- Wire debug level during early CLI argument parsing
+- Add bash, zsh, fish completions for --debug levels

completions/_fabric

@@ -145,6 +145,7 @@ _fabric() {
     '(--transcribe-file)--transcribe-file[Audio or video file to transcribe]:audio file:_files -g "*.mp3 *.mp4 *.mpeg *.mpga *.m4a *.wav *.webm"' \
     '(--transcribe-model)--transcribe-model[Model to use for transcription (separate from chat model)]:transcribe model:_fabric_transcription_models' \
     '(--split-media-file)--split-media-file[Split audio/video files larger than 25MB using ffmpeg]' \
+    '(--debug)--debug[Set debug level (0=off, 1=basic, 2=detailed, 3=trace)]:debug level:(0 1 2 3)' \
     '(--notification)--notification[Send desktop notification when command completes]' \
     '(--notification-command)--notification-command[Custom command to run for notifications]:notification command:' \
     '(-h --help)'{-h,--help}'[Show this help message]' \

completions/fabric.bash

@@ -13,7 +13,7 @@ _fabric() {
   _get_comp_words_by_ref -n : cur prev words cword
 
   # Define all possible options/flags
-  local opts="--pattern -p --variable -v --context -C --session --attachment -a --setup -S --temperature -t --topp -T --stream -s --presencepenalty -P --raw -r --frequencypenalty -F --listpatterns -l --listmodels -L --listcontexts -x --listsessions -X --updatepatterns -U --copy -c --model -m --vendor -V --modelContextLength --output -o --output-session --latest -n --changeDefaultModel -d --youtube -y --playlist --transcript --transcript-with-timestamps --comments --metadata --yt-dlp-args --language -g --scrape_url -u --scrape_question -q --seed -e --thinking --wipecontext -w --wipesession -W --printcontext --printsession --readability --input-has-vars --no-variable-replacement --dry-run --serve --serveOllama --address --api-key --config --search --search-location --image-file --image-size --image-quality --image-compression --image-background --suppress-think --think-start-tag --think-end-tag --disable-responses-api --transcribe-file --transcribe-model --split-media-file --voice --list-gemini-voices --notification --notification-command --version --listextensions --addextension --rmextension --strategy --liststrategies --listvendors --shell-complete-list --help -h"
+  local opts="--pattern -p --variable -v --context -C --session --attachment -a --setup -S --temperature -t --topp -T --stream -s --presencepenalty -P --raw -r --frequencypenalty -F --listpatterns -l --listmodels -L --listcontexts -x --listsessions -X --updatepatterns -U --copy -c --model -m --vendor -V --modelContextLength --output -o --output-session --latest -n --changeDefaultModel -d --youtube -y --playlist --transcript --transcript-with-timestamps --comments --metadata --yt-dlp-args --language -g --scrape_url -u --scrape_question -q --seed -e --thinking --wipecontext -w --wipesession -W --printcontext --printsession --readability --input-has-vars --no-variable-replacement --dry-run --serve --serveOllama --address --api-key --config --search --search-location --image-file --image-size --image-quality --image-compression --image-background --suppress-think --think-start-tag --think-end-tag --disable-responses-api --transcribe-file --transcribe-model --split-media-file --voice --list-gemini-voices --notification --notification-command --debug --version --listextensions --addextension --rmextension --strategy --liststrategies --listvendors --shell-complete-list --help -h"
 
   # Helper function for dynamic completions
   _fabric_get_list() {
@@ -78,6 +78,10 @@ _fabric() {
     COMPREPLY=($(compgen -W "$(_fabric_get_list --list-transcription-models)" -- "${cur}"))
     return 0
     ;;
+  --debug)
+    COMPREPLY=($(compgen -W "0 1 2 3" -- "${cur}"))
+    return 0
+    ;;
   # Options requiring file/directory paths
   -a | --attachment | -o | --output | --config | --addextension | --image-file | --transcribe-file)
     _filedir

completions/fabric.fish

@@ -99,6 +99,7 @@ function __fabric_register_completions
         complete -c $cmd -l voice -d "TTS voice name for supported models (e.g., Kore, Charon, Puck)" -a "(__fabric_get_gemini_voices)"
         complete -c $cmd -l transcribe-file -d "Audio or video file to transcribe" -r -a "*.mp3 *.mp4 *.mpeg *.mpga *.m4a *.wav *.webm"
         complete -c $cmd -l transcribe-model -d "Model to use for transcription (separate from chat model)" -a "(__fabric_get_transcription_models)"
+        complete -c $cmd -l debug -d "Set debug level (0=off, 1=basic, 2=detailed, 3=trace)" -a "0 1 2 3"
         complete -c $cmd -l notification-command -d "Custom command to run for notifications (overrides built-in notifications)"
 
         # Boolean flags (no arguments)

docs/Using-Speech-To-Text.md

@@ -0,0 +1,139 @@
+# Using Speech-To-Text (STT) with Fabric
+
+Fabric supports speech-to-text transcription of audio and video files using OpenAI's transcription models. This feature allows you to convert spoken content into text that can then be processed through Fabric's patterns.
+
+## Overview
+
+The STT feature integrates OpenAI's Whisper and GPT-4o transcription models to convert audio/video files into text. The transcribed text is automatically passed as input to your chosen pattern or chat session.
+
+## Requirements
+
+- OpenAI API key configured in Fabric
+- For files larger than 25MB: `ffmpeg` installed on your system
+- Supported audio/video formats: `.mp3`, `.mp4`, `.mpeg`, `.mpga`, `.m4a`, `.wav`, `.webm`
+
+## Basic Usage
+
+### Simple Transcription
+
+To transcribe an audio file and send the result to a pattern:
+
+```bash
+fabric --transcribe-file /path/to/audio.mp3 --transcribe-model whisper-1 --pattern summarize
+```
+
+### Transcription Only
+
+To just transcribe a file without applying a pattern:
+
+```bash
+fabric --transcribe-file /path/to/audio.mp3 --transcribe-model whisper-1
+```
+
+## Command Line Flags
+
+### Required Flags
+
+- `--transcribe-file`: Path to the audio or video file to transcribe
+- `--transcribe-model`: Model to use for transcription (required when using transcription)
+
+### Optional Flags
+
+- `--split-media-file`: Automatically split files larger than 25MB into chunks using ffmpeg
+
+## Available Models
+
+You can list all available transcription models with:
+
+```bash
+fabric --list-transcription-models
+```
+
+Currently supported models:
+
+- `whisper-1`: OpenAI's Whisper model
+- `gpt-4o-mini-transcribe`: GPT-4o Mini transcription model
+- `gpt-4o-transcribe`: GPT-4o transcription model
+
+## File Size Handling
+
+### Files Under 25MB
+
+Files under the 25MB limit are processed directly without any special handling.
+
+### Files Over 25MB
+
+For files exceeding OpenAI's 25MB limit, you have two options:
+
+1. **Manual handling**: The command will fail with an error message suggesting to use `--split-media-file`
+2. **Automatic splitting**: Use the `--split-media-file` flag to automatically split the file into chunks
+
+```bash
+fabric --transcribe-file large_recording.mp4 --transcribe-model whisper-1 --split-media-file --pattern summarize
+```
+
+When splitting is enabled:
+
+- Fabric uses `ffmpeg` to split the file into 10-minute segments initially
+- If segments are still too large, it reduces the segment time by half repeatedly
+- All segments are transcribed and the results are concatenated
+- Temporary files are automatically cleaned up after processing
+
+## Integration with Patterns
+
+The transcribed text is seamlessly integrated into Fabric's workflow:
+
+1. File is transcribed using the specified model
+2. Transcribed text becomes the input message
+3. Text is sent to the specified pattern or chat session
+
+### Example Workflows
+
+**Meeting transcription and summarization:**
+
+```bash
+fabric --transcribe-file meeting.mp4 --transcribe-model gpt-4o-transcribe --pattern summarize
+```
+
+**Interview analysis:**
+
+```bash
+fabric --transcribe-file interview.mp3 --transcribe-model whisper-1 --pattern extract_insights
+```
+
+**Large video file processing:**
+
+```bash
+fabric --transcribe-file presentation.mp4 --transcribe-model gpt-4o-transcribe --split-media-file --pattern create_summary
+```
+
+## Error Handling
+
+Common error scenarios:
+
+- **Unsupported format**: Only the listed audio/video formats are supported
+- **File too large**: Use `--split-media-file` for files over 25MB
+- **Missing ffmpeg**: Install ffmpeg for automatic file splitting
+- **Invalid model**: Use `--list-transcription-models` to see available models
+- **Missing model**: The `--transcribe-model` flag is required when using `--transcribe-file`
+
+## Technical Details
+
+### Implementation
+
+- Transcription is handled in `internal/cli/transcribe.go:14`
+- OpenAI-specific implementation in `internal/plugins/ai/openai/openai_audio.go:41`
+- File splitting uses ffmpeg with configurable segment duration
+- Supports any vendor that implements the `transcriber` interface
+
+### Processing Pipeline
+
+1. CLI validates file format and size
+2. If file > 25MB and splitting enabled, file is split using ffmpeg
+3. Each file/segment is sent to OpenAI's transcription API
+4. Results are concatenated with spaces between segments
+5. Transcribed text is passed as input to the main Fabric pipeline
+
+### Vendor Support
+
+Currently, only OpenAI is supported for transcription, but the interface allows for future expansion to other vendors that provide transcription capabilities.

internal/cli/flags.go

@@ -13,6 +13,7 @@ import (
 
 	"github.com/danielmiessler/fabric/internal/chat"
 	"github.com/danielmiessler/fabric/internal/domain"
+	debuglog "github.com/danielmiessler/fabric/internal/log"
 	"github.com/danielmiessler/fabric/internal/util"
 	"github.com/jessevdk/go-flags"
 	"golang.org/x/text/language"
@@ -101,18 +102,12 @@ type Flags struct {
 	Notification                    bool                 `long:"notification" yaml:"notification" description:"Send desktop notification when command completes"`
 	NotificationCommand             string               `long:"notification-command" yaml:"notificationCommand" description:"Custom command to run for notifications (overrides built-in notifications)"`
 	Thinking                        domain.ThinkingLevel `long:"thinking" yaml:"thinking" description:"Set reasoning/thinking level (e.g., off, low, medium, high, or numeric tokens for Anthropic or Google Gemini)"`
-}
-
-var debug = false
-
-func Debugf(format string, a ...interface{}) {
-	if debug {
-		fmt.Printf("DEBUG: "+format, a...)
-	}
+	Debug                           int                  `long:"debug" description:"Set debug level (0=off, 1=basic, 2=detailed, 3=trace)" default:"0"`
 }
 
 // Init Initialize flags. returns a Flags struct and an error
 func Init() (ret *Flags, err error) {
+	debuglog.SetLevel(debuglog.LevelFromInt(parseDebugLevel(os.Args[1:])))
 	// Track which yaml-configured flags were set on CLI
 	usedFlags := make(map[string]bool)
 	yamlArgsScan := os.Args[1:]
@@ -128,11 +123,11 @@ func Init() (ret *Flags, err error) {
 			shortTag := field.Tag.Get("short")
 			if longTag != "" {
 				flagToYamlTag[longTag] = yamlTag
-				Debugf("Mapped long flag %s to yaml tag %s\n", longTag, yamlTag)
+				debuglog.Debug(debuglog.Detailed, "Mapped long flag %s to yaml tag %s\n", longTag, yamlTag)
 			}
 			if shortTag != "" {
 				flagToYamlTag[shortTag] = yamlTag
-				Debugf("Mapped short flag %s to yaml tag %s\n", shortTag, yamlTag)
+				debuglog.Debug(debuglog.Detailed, "Mapped short flag %s to yaml tag %s\n", shortTag, yamlTag)
 			}
 		}
 	}
@@ -144,7 +139,7 @@ func Init() (ret *Flags, err error) {
 		if flag != "" {
 			if yamlTag, exists := flagToYamlTag[flag]; exists {
 				usedFlags[yamlTag] = true
-				Debugf("CLI flag used: %s (yaml: %s)\n", flag, yamlTag)
+				debuglog.Debug(debuglog.Detailed, "CLI flag used: %s (yaml: %s)\n", flag, yamlTag)
 			}
 		}
 	}
@@ -156,6 +151,7 @@ func Init() (ret *Flags, err error) {
 	if args, err = parser.Parse(); err != nil {
 		return
 	}
+	debuglog.SetLevel(debuglog.LevelFromInt(ret.Debug))
 
 	// Check to see if a ~/.config/fabric/config.yaml config file exists (only when user didn't specify a config)
 	if ret.Config == "" {
@@ -163,7 +159,7 @@ func Init() (ret *Flags, err error) {
 		if defaultConfigPath, err := util.GetDefaultConfigPath(); err == nil && defaultConfigPath != "" {
 			ret.Config = defaultConfigPath
 		} else if err != nil {
-			Debugf("Could not determine default config path: %v\n", err)
+			debuglog.Debug(debuglog.Detailed, "Could not determine default config path: %v\n", err)
 		}
 	}
 
@@ -188,13 +184,13 @@ func Init() (ret *Flags, err error) {
 					if flagField.CanSet() {
 						if yamlField.Type() != flagField.Type() {
 							if err := assignWithConversion(flagField, yamlField); err != nil {
-								Debugf("Type conversion failed for %s: %v\n", yamlTag, err)
+								debuglog.Debug(debuglog.Detailed, "Type conversion failed for %s: %v\n", yamlTag, err)
 								continue
 							}
 						} else {
 							flagField.Set(yamlField)
 						}
-						Debugf("Applied YAML value for %s: %v\n", yamlTag, yamlField.Interface())
+						debuglog.Debug(debuglog.Detailed, "Applied YAML value for %s: %v\n", yamlTag, yamlField.Interface())
 					}
 				}
 			}
@@ -220,6 +216,22 @@ func Init() (ret *Flags, err error) {
 	return
 }
 
+func parseDebugLevel(args []string) int {
+	for i := 0; i < len(args); i++ {
+		arg := args[i]
+		if arg == "--debug" && i+1 < len(args) {
+			if lvl, err := strconv.Atoi(args[i+1]); err == nil {
+				return lvl
+			}
+		} else if strings.HasPrefix(arg, "--debug=") {
+			if lvl, err := strconv.Atoi(strings.TrimPrefix(arg, "--debug=")); err == nil {
+				return lvl
+			}
+		}
+	}
+	return 0
+}
+
 func extractFlag(arg string) string {
 	var flag string
 	if strings.HasPrefix(arg, "--") {
@@ -289,7 +301,7 @@ func loadYAMLConfig(configPath string) (*Flags, error) {
 		return nil, fmt.Errorf("error parsing config file: %w", err)
 	}
 
-	Debugf("Config: %v\n", config)
+	debuglog.Debug(debuglog.Detailed, "Config: %v\n", config)
 
 	return config, nil
 }

internal/log/log.go

@@ -0,0 +1,69 @@
+package log
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"sync"
+)
+
+// Level represents the debug verbosity.
+type Level int
+
+const (
+	// Off disables all debug output.
+	Off Level = iota
+	// Basic provides minimal debugging information.
+	Basic
+	// Detailed provides more verbose debugging.
+	Detailed
+	// Trace is the most verbose level.
+	Trace
+)
+
+var (
+	mu     sync.RWMutex
+	level  Level     = Off
+	output io.Writer = os.Stderr
+)
+
+// SetLevel sets the global debug level.
+func SetLevel(l Level) {
+	mu.Lock()
+	level = l
+	mu.Unlock()
+}
+
+// LevelFromInt converts an int to a Level.
+func LevelFromInt(i int) Level {
+	switch {
+	case i <= 0:
+		return Off
+	case i == 1:
+		return Basic
+	case i == 2:
+		return Detailed
+	case i >= 3:
+		return Trace
+	default:
+		return Off
+	}
+}
+
+// Debug writes a debug message if the global level permits.
+func Debug(l Level, format string, a ...interface{}) {
+	mu.RLock()
+	current := level
+	w := output
+	mu.RUnlock()
+	if current >= l {
+		fmt.Fprintf(w, "DEBUG: "+format, a...)
+	}
+}
+
+// SetOutput allows overriding the output destination for debug logs.
+func SetOutput(w io.Writer) {
+	mu.Lock()
+	output = w
+	mu.Unlock()
+}

internal/plugins/ai/openai/openai_audio.go

@@ -11,6 +11,8 @@ import (
 	"sort"
 	"strings"
 
+	debuglog "github.com/danielmiessler/fabric/internal/log"
+
 	openai "github.com/openai/openai-go"
 )
 
@@ -56,18 +58,14 @@ func (o *Client) TranscribeFile(ctx context.Context, filePath, model string, spl
 		return "", err
 	}
 
-	debug := os.Getenv("FABRIC_STT_DEBUG") != ""
-
 	var files []string
 	var cleanup func()
 	if info.Size() > MaxAudioFileSize {
 		if !split {
 			return "", fmt.Errorf("file %s exceeds 25MB limit; use --split-media-file to enable automatic splitting", filePath)
 		}
-		if debug {
-			fmt.Fprintf(os.Stderr, "File %s is larger than the size limit... breaking it up into chunks...\n", filePath)
-		}
-		if files, cleanup, err = splitAudioFile(filePath, ext, MaxAudioFileSize, debug); err != nil {
+		debuglog.Debug(debuglog.Basic, "File %s is larger than the size limit... breaking it up into chunks...\n", filePath)
+		if files, cleanup, err = splitAudioFile(filePath, ext, MaxAudioFileSize); err != nil {
 			return "", err
 		}
 		defer cleanup()
@@ -77,9 +75,7 @@ func (o *Client) TranscribeFile(ctx context.Context, filePath, model string, spl
 
 	var builder strings.Builder
 	for i, f := range files {
-		if debug {
-			fmt.Fprintf(os.Stderr, "Using model %s to transcribe part %d (file name: %s)...\n", model, i+1, f)
-		}
+		debuglog.Debug(debuglog.Basic, "Using model %s to transcribe part %d (file name: %s)...\n", model, i+1, f)
 		var chunk *os.File
 		if chunk, err = os.Open(f); err != nil {
 			return "", err
@@ -105,7 +101,7 @@ func (o *Client) TranscribeFile(ctx context.Context, filePath, model string, spl
 
 // splitAudioFile splits the source file into chunks smaller than maxSize using ffmpeg.
 // It returns the list of chunk file paths and a cleanup function.
-func splitAudioFile(src, ext string, maxSize int64, debug bool) (files []string, cleanup func(), err error) {
+func splitAudioFile(src, ext string, maxSize int64) (files []string, cleanup func(), err error) {
 	if _, err = exec.LookPath("ffmpeg"); err != nil {
 		return nil, nil, fmt.Errorf("ffmpeg not found: please install it")
 	}
@@ -119,9 +115,7 @@ func splitAudioFile(src, ext string, maxSize int64, debug bool) (files []string,
 	segmentTime := 600 // start with 10 minutes
 	for {
 		pattern := filepath.Join(dir, "chunk-%03d"+ext)
-		if debug {
-			fmt.Fprintf(os.Stderr, "Running ffmpeg to split audio into %d-second chunks...\n", segmentTime)
-		}
+		debuglog.Debug(debuglog.Basic, "Running ffmpeg to split audio into %d-second chunks...\n", segmentTime)
 		cmd := exec.Command("ffmpeg", "-y", "-i", src, "-f", "segment", "-segment_time", fmt.Sprintf("%d", segmentTime), "-c", "copy", pattern)
 		var stderr bytes.Buffer
 		cmd.Stderr = &stderr

internal/plugins/ai/vendors.go

@@ -148,7 +148,6 @@ func (o *VendorsManager) setupVendorTo(vendor Vendor, configuredVendors map[stri
 		delete(configuredVendors, vendor.GetName())
 		fmt.Printf("[%v] skipped\n", vendor.GetName())
 	}
-	return
 }
 
 type modelResult struct {

internal/plugins/template/extension_registry.go

@@ -10,8 +10,9 @@ import (
 	"strings"
 	"time"
 
+	debuglog "github.com/danielmiessler/fabric/internal/log"
+
 	"gopkg.in/yaml.v3"
-	// Add this import
 )
 
 // ExtensionDefinition represents a single extension configuration
@@ -87,9 +88,7 @@ func NewExtensionRegistry(configDir string) *ExtensionRegistry {
 	r.ensureConfigDir()
 
 	if err := r.loadRegistry(); err != nil {
-		if Debug {
-			fmt.Printf("Warning: could not load extension registry: %v\n", err)
-		}
+		debuglog.Debug(debuglog.Basic, "Warning: could not load extension registry: %v\n", err)
 	}
 
 	return r

internal/plugins/template/template.go

@@ -6,6 +6,8 @@ import (
 	"path/filepath"
 	"regexp"
 	"strings"
+
+	debuglog "github.com/danielmiessler/fabric/internal/log"
 )
 
 var (
@@ -14,7 +16,6 @@ var (
 	filePlugin     = &FilePlugin{}
 	fetchPlugin    = &FetchPlugin{}
 	sysPlugin      = &SysPlugin{}
-	Debug          = false // Debug flag
 )
 
 var extensionManager *ExtensionManager
@@ -33,9 +34,7 @@ var pluginPattern = regexp.MustCompile(`\{\{plugin:([^:]+):([^:]+)(?::([^}]+))?\
 var extensionPattern = regexp.MustCompile(`\{\{ext:([^:]+):([^:]+)(?::([^}]+))?\}\}`)
 
 func debugf(format string, a ...interface{}) {
-	if Debug {
-		fmt.Printf(format, a...)
-	}
+	debuglog.Debug(debuglog.Trace, format, a...)
 }
 
 func ApplyTemplate(content string, variables map[string]string, input string) (string, error) {