diff --git a/cmd/sketch/main.go b/cmd/sketch/main.go
index 0594778..7bfcf38 100644
--- a/cmd/sketch/main.go
+++ b/cmd/sketch/main.go
@@ -294,6 +294,8 @@
 	bashSlowTimeout       string
 	bashBackgroundTimeout string
 	passthroughUpstream   bool
+	// Claude debugging
+	dumpAntCalls bool
 }
 
 // parseCLIFlags parses all command-line flags and returns a CLIFlags struct
@@ -369,6 +371,7 @@
 	// Internal flags for development/debugging
 	internalFlags.StringVar(&flags.dumpDist, "dump-dist", "", "(internal) dump embedded /dist/ filesystem to specified directory and exit")
 	internalFlags.StringVar(&flags.subtraceToken, "subtrace-token", "", "(development) run sketch under subtrace.dev with the provided token")
+	internalFlags.BoolVar(&flags.dumpAntCalls, "dump-ant-calls", false, "(debugging) dump raw communications with Claude to files in ~/.cache/sketch/")
 
 	// Custom usage function that shows only user-visible flags by default
 	userFlags.Usage = func() {
@@ -518,6 +521,7 @@
 		SubtraceToken:       flags.subtraceToken,
 		MCPServers:          flags.mcpServers,
 		PassthroughUpstream: flags.passthroughUpstream,
+		DumpAntCalls:        flags.dumpAntCalls,
 	}
 
 	if err := dockerimg.LaunchContainer(ctx, config); err != nil {
@@ -628,7 +632,7 @@
 		}
 	}
 
-	llmService, err := selectLLMService(nil, flags.modelName, modelURL, apiKey)
+	llmService, err := selectLLMService(nil, flags, modelURL, apiKey)
 	if err != nil {
 		return fmt.Errorf("failed to initialize LLM service: %w", err)
 	}
@@ -895,19 +899,20 @@
 // If modelName is "gemini", it uses the Gemini service.
 // Otherwise, it tries to use the OpenAI service with the specified model.
 // Returns an error if the model name is not recognized or if required configuration is missing.
-func selectLLMService(client *http.Client, modelName string, modelURL, apiKey string) (llm.Service, error) {
-	if modelName == "" || modelName == "claude" {
+func selectLLMService(client *http.Client, flags CLIFlags, modelURL, apiKey string) (llm.Service, error) {
+	if flags.modelName == "" || flags.modelName == "claude" {
 		if apiKey == "" {
 			return nil, fmt.Errorf("missing ANTHROPIC_API_KEY")
 		}
 		return &ant.Service{
-			HTTPC:  client,
-			URL:    modelURL,
-			APIKey: apiKey,
+			HTTPC:        client,
+			URL:          modelURL,
+			APIKey:       apiKey,
+			DumpAntCalls: flags.dumpAntCalls,
 		}, nil
 	}
 
-	if modelName == "gemini" {
+	if flags.modelName == "gemini" {
 		if apiKey == "" {
 			return nil, fmt.Errorf("missing %s", gem.GeminiAPIKeyEnv)
 		}
@@ -919,9 +924,9 @@
 		}, nil
 	}
 
-	model := oai.ModelByUserName(modelName)
+	model := oai.ModelByUserName(flags.modelName)
 	if model == nil {
-		return nil, fmt.Errorf("unknown model '%s', use -list-models to see available models", modelName)
+		return nil, fmt.Errorf("unknown model '%s', use -list-models to see available models", flags.modelName)
 	}
 
 	// Verify we have an API key, if necessary.
diff --git a/dockerimg/dockerimg.go b/dockerimg/dockerimg.go
index abf3421..d545a68 100644
--- a/dockerimg/dockerimg.go
+++ b/dockerimg/dockerimg.go
@@ -139,6 +139,9 @@
 
 	// PassthroughUpstream configures upstream remote for passthrough to innie
 	PassthroughUpstream bool
+
+	// DumpAntCalls enables dumping raw communications with Claude to files
+	DumpAntCalls bool
 }
 
 // LaunchContainer creates a docker container for a project, installs sketch and opens a connection to it.
@@ -645,6 +648,9 @@
 	if config.PassthroughUpstream {
 		cmdArgs = append(cmdArgs, "-passthrough-upstream")
 	}
+	if config.DumpAntCalls {
+		cmdArgs = append(cmdArgs, "-dump-ant-calls")
+	}
 
 	// Add additional docker arguments if provided
 	if config.DockerArgs != "" {
diff --git a/llm/ant/ant.go b/llm/ant/ant.go
index 2afc69f..0b65d48 100644
--- a/llm/ant/ant.go
+++ b/llm/ant/ant.go
@@ -59,11 +59,12 @@
 // Service provides Claude completions.
 // Fields should not be altered concurrently with calling any method on Service.
 type Service struct {
-	HTTPC     *http.Client // defaults to http.DefaultClient if nil
-	URL       string       // defaults to DefaultURL if empty
-	APIKey    string       // must be non-empty
-	Model     string       // defaults to DefaultModel if empty
-	MaxTokens int          // defaults to DefaultMaxTokens if zero
+	HTTPC        *http.Client // defaults to http.DefaultClient if nil
+	URL          string       // defaults to DefaultURL if empty
+	APIKey       string       // must be non-empty
+	Model        string       // defaults to DefaultModel if empty
+	MaxTokens    int          // defaults to DefaultMaxTokens if zero
+	DumpAntCalls bool         // whether to dump request/response text to files for debugging; defaults to false
 }
 
 var _ llm.Service = (*Service)(nil)
@@ -209,13 +210,8 @@
 	TokenEfficientToolUse bool `json:"-"` // DO NOT USE, broken on Anthropic's side as of 2025-02-28
 }
 
-const dumpText = false // debugging toggle to dump raw communications with Claude using dumpToFile
-
 // dumpToFile writes the content to a timestamped file in ~/.cache/sketch/, with typ in the filename.
 func dumpToFile(typ string, content []byte) error {
-	if !dumpText {
-		return nil
-	}
 	homeDir, err := os.UserHomeDir()
 	if err != nil {
 		return err
@@ -444,7 +440,7 @@
 
 	var payload []byte
 	var err error
-	if dumpText || testing.Testing() {
+	if s.DumpAntCalls || testing.Testing() {
 		payload, err = json.MarshalIndent(request, "", " ")
 	} else {
 		payload, err = json.Marshal(request)
@@ -476,8 +472,10 @@
 			slog.WarnContext(ctx, "anthropic request sleep before retry", "sleep", sleep, "attempts", attempts)
 			time.Sleep(sleep)
 		}
-		if err := dumpToFile("request", payload); err != nil {
-			slog.WarnContext(ctx, "failed to dump request to file", "error", err)
+		if s.DumpAntCalls {
+			if err := dumpToFile("request", payload); err != nil {
+				slog.WarnContext(ctx, "failed to dump request to file", "error", err)
+			}
 		}
 		req, err := http.NewRequestWithContext(ctx, "POST", url, bytes.NewReader(payload))
 		if err != nil {
@@ -518,8 +516,10 @@
 
 		switch {
 		case resp.StatusCode == http.StatusOK:
-			if err := dumpToFile("response", buf); err != nil {
-				slog.WarnContext(ctx, "failed to dump response to file", "error", err)
+			if s.DumpAntCalls {
+				if err := dumpToFile("response", buf); err != nil {
+					slog.WarnContext(ctx, "failed to dump response to file", "error", err)
+				}
 			}
 			var response response
 			err = json.NewDecoder(bytes.NewReader(buf)).Decode(&response)