diff --git a/pkg/errorutil/errors.go b/pkg/errorutil/errors.go
index ad0dd20d18f..afc34f5d95c 100644
--- a/pkg/errorutil/errors.go
+++ b/pkg/errorutil/errors.go
@@ -2,7 +2,13 @@
 // returned by the GitHub API and gh CLI.
 package errorutil
 
-import "strings"
+import (
+	"strings"
+
+	"github.com/github/gh-aw/pkg/logger"
+)
+
+var errorutilLog = logger.New("errorutil:errors")
 
 // IsNotFoundError reports whether err represents an HTTP 404 / "not found" response.
 // It returns false when err is nil.
@@ -10,7 +16,11 @@ import "strings"
 // the phrase "not found", which covers all known forms returned by the GitHub API,
 // the gh CLI, and the go-gh library.
 func IsNotFoundError(err error) bool {
-	return containsErrorSubstring(err, "404", "not found")
+	matched := containsErrorSubstring(err, "404", "not found")
+	if matched {
+		errorutilLog.Printf("Classified error as not-found (404): %v", err)
+	}
+	return matched
 }
 
 // IsForbiddenError reports whether err represents an HTTP 403 / "forbidden" response.
@@ -19,7 +29,11 @@ func IsNotFoundError(err error) bool {
 // "HTTP 403" or "403 Forbidden", which avoids misclassifying unrelated errors
 // like "forbidden character".
 func IsForbiddenError(err error) bool {
-	return containsHTTPStatusSubstring(err, "403", "forbidden")
+	matched := containsHTTPStatusSubstring(err, "403", "forbidden")
+	if matched {
+		errorutilLog.Printf("Classified error as forbidden (403): %v", err)
+	}
+	return matched
 }
 
 // IsGoneError reports whether err represents an HTTP 410 / "gone" response.
@@ -28,7 +42,11 @@ func IsForbiddenError(err error) bool {
 // "HTTP 410" or "410 Gone", which avoids misclassifying unrelated errors like
 // "connection has gone away".
 func IsGoneError(err error) bool {
-	return containsHTTPStatusSubstring(err, "410", "gone")
+	matched := containsHTTPStatusSubstring(err, "410", "gone")
+	if matched {
+		errorutilLog.Printf("Classified error as gone (410): %v", err)
+	}
+	return matched
 }
 
 // containsErrorSubstring reports whether err contains any of the provided
diff --git a/pkg/jsonutil/json.go b/pkg/jsonutil/json.go
index 5b3397469f2..cecf3963ff6 100644
--- a/pkg/jsonutil/json.go
+++ b/pkg/jsonutil/json.go
@@ -4,8 +4,12 @@ import (
 	"bytes"
 	"encoding/json"
 	"strings"
+
+	"github.com/github/gh-aw/pkg/logger"
 )
 
+var jsonutilLog = logger.New("jsonutil:json")
+
 // MarshalCompactNoHTMLEscape marshals a value to compact JSON without HTML escaping.
 // It trims the trailing newline emitted by json.Encoder.
 func MarshalCompactNoHTMLEscape(v any) (string, error) {
@@ -13,8 +17,11 @@ func MarshalCompactNoHTMLEscape(v any) (string, error) {
 	encoder := json.NewEncoder(&buf)
 	encoder.SetEscapeHTML(false)
 	if err := encoder.Encode(v); err != nil {
+		jsonutilLog.Printf("MarshalCompactNoHTMLEscape encode failed: %v", err)
 		return "", err
 	}
 
-	return strings.TrimSuffix(buf.String(), "\n"), nil
+	result := strings.TrimSuffix(buf.String(), "\n")
+	jsonutilLog.Printf("MarshalCompactNoHTMLEscape produced %d bytes", len(result))
+	return result, nil
 }
diff --git a/pkg/syncutil/onceloader.go b/pkg/syncutil/onceloader.go
index 758391f2dcd..dcea16c21a6 100644
--- a/pkg/syncutil/onceloader.go
+++ b/pkg/syncutil/onceloader.go
@@ -1,6 +1,12 @@
 package syncutil
 
-import "sync"
+import (
+	"sync"
+
+	"github.com/github/gh-aw/pkg/logger"
+)
+
+var syncutilLog = logger.New("syncutil:onceloader")
 
 // OnceLoader caches the result of a fallible, expensive one-shot fetch.
 // Safe for concurrent use; loader is invoked at most once.
@@ -17,8 +23,14 @@ func (o *OnceLoader[T]) Get(loader func() (T, error)) (T, error) {
 	defer o.mu.Unlock()
 
 	if !o.done {
+		syncutilLog.Print("OnceLoader.Get: cache miss, invoking loader")
 		o.result, o.err = loader()
 		o.done = true
+		if o.err != nil {
+			syncutilLog.Printf("OnceLoader.Get: loader failed: %v", o.err)
+		} else {
+			syncutilLog.Print("OnceLoader.Get: loader succeeded, result cached")
+		}
 	}
 
 	return o.result, o.err
@@ -29,6 +41,7 @@ func (o *OnceLoader[T]) Reset() {
 	o.mu.Lock()
 	defer o.mu.Unlock()
 
+	syncutilLog.Print("OnceLoader.Reset: clearing cached state")
 	var zero T
 	o.result = zero
 	o.err = nil
@@ -42,6 +55,7 @@ func (o *OnceLoader[T]) Override(result T, err error) {
 	o.mu.Lock()
 	defer o.mu.Unlock()
 
+	syncutilLog.Printf("OnceLoader.Override: storing cached value (err=%v)", err)
 	o.result = result
 	o.err = err
 	o.done = true
diff --git a/pkg/workflow/safe_outputs_workflow_helpers.go b/pkg/workflow/safe_outputs_workflow_helpers.go
index 732786e1cc9..e3ac4de9e99 100644
--- a/pkg/workflow/safe_outputs_workflow_helpers.go
+++ b/pkg/workflow/safe_outputs_workflow_helpers.go
@@ -4,9 +4,12 @@ import (
 	"fmt"
 	"sort"
 
+	"github.com/github/gh-aw/pkg/logger"
 	"github.com/github/gh-aw/pkg/stringutil"
 )
 
+var safeOutputsWorkflowHelpersLog = logger.New("workflow:safe_outputs_workflow_helpers")
+
 type workflowToolDefinitionOptions struct {
 	workflowName      string
 	workflowInputs    map[string]any
@@ -16,6 +19,7 @@ type workflowToolDefinitionOptions struct {
 
 func generateWorkflowToolDefinition(opts workflowToolDefinitionOptions) map[string]any {
 	toolName := stringutil.NormalizeSafeOutputIdentifier(opts.workflowName)
+	safeOutputsWorkflowHelpersLog.Printf("Generating workflow tool definition: workflow=%s, tool=%s, inputs=%d", opts.workflowName, toolName, len(opts.workflowInputs))
 	description := fmt.Sprintf(opts.descriptionFormat, opts.workflowName)
 	properties, required := buildInputSchema(opts.workflowInputs, func(inputName string) string {
 		return fmt.Sprintf("Input parameter '%s' for workflow %s", inputName, opts.workflowName)
@@ -35,6 +39,7 @@ func generateWorkflowToolDefinition(opts workflowToolDefinitionOptions) map[stri
 	if len(required) > 0 {
 		sort.Strings(required)
 		tool["inputSchema"].(map[string]any)["required"] = required
+		safeOutputsWorkflowHelpersLog.Printf("Workflow tool %s has %d required inputs", toolName, len(required))
 	}
 
 	return tool
@@ -42,15 +47,19 @@ func generateWorkflowToolDefinition(opts workflowToolDefinitionOptions) map[stri
 
 func resolveWorkflowExtension(fileResult *findWorkflowFileResult) (string, bool) {
 	if fileResult.lockExists {
+		safeOutputsWorkflowHelpersLog.Print("Resolved workflow extension: .lock.yml (lock file exists)")
 		return ".lock.yml", true
 	}
 	if fileResult.ymlExists {
+		safeOutputsWorkflowHelpersLog.Print("Resolved workflow extension: .yml (yml file exists)")
 		return ".yml", true
 	}
 	if fileResult.mdExists {
 		// .md-only: the workflow is a same-batch compilation target that will produce a .lock.yml
+		safeOutputsWorkflowHelpersLog.Print("Resolved workflow extension: .lock.yml (md-only, same-batch target)")
 		return ".lock.yml", true
 	}
 
+	safeOutputsWorkflowHelpersLog.Print("Failed to resolve workflow extension: no candidate files exist")
 	return "", false
 }
diff --git a/pkg/workflow/workflow_inputs_extractor.go b/pkg/workflow/workflow_inputs_extractor.go
index 074f75513f6..2ea0b0979e0 100644
--- a/pkg/workflow/workflow_inputs_extractor.go
+++ b/pkg/workflow/workflow_inputs_extractor.go
@@ -3,12 +3,17 @@ package workflow
 import (
 	"os"
 
+	"github.com/github/gh-aw/pkg/logger"
 	"github.com/github/gh-aw/pkg/parser"
 )
 
+var workflowInputsExtractorLog = logger.New("workflow:workflow_inputs_extractor")
+
 func extractInputsFromYAML(workflowPath, trigger string) (map[string]any, error) {
+	workflowInputsExtractorLog.Printf("Extracting inputs from YAML: path=%s, trigger=%s", workflowPath, trigger)
 	workflow, err := readWorkflowYAML(workflowPath)
 	if err != nil {
+		workflowInputsExtractorLog.Printf("Failed to read workflow YAML: %v", err)
 		return nil, err
 	}
 
@@ -16,13 +21,16 @@ func extractInputsFromYAML(workflowPath, trigger string) (map[string]any, error)
 }
 
 func extractInputsFromMarkdown(mdPath, trigger string) (map[string]any, error) {
+	workflowInputsExtractorLog.Printf("Extracting inputs from markdown: path=%s, trigger=%s", mdPath, trigger)
 	content, err := os.ReadFile(mdPath) // #nosec G304 -- mdPath is validated via isPathWithinDir in findWorkflowFile
 	if err != nil {
+		workflowInputsExtractorLog.Printf("Failed to read markdown file: %v", err)
 		return nil, err
 	}
 
 	result, err := parser.ExtractFrontmatterFromContent(string(content))
 	if err != nil || result == nil {
+		workflowInputsExtractorLog.Printf("No frontmatter extracted (err=%v), returning empty inputs", err)
 		return make(map[string]any), nil
 	}
 
@@ -60,5 +68,6 @@ func extractInputsFromParsedWorkflow(workflow map[string]any, trigger string) ma
 		return make(map[string]any)
 	}
 
+	workflowInputsExtractorLog.Printf("Found %d inputs for trigger %s", len(inputsMap), trigger)
 	return inputsMap
 }