feat: add tri-state support for disable-image-generation configuration

- Introduced `DisableImageGenerationMode` with support for `false`, `true`, and `chat` values.
- Updated payload handling to preserve `image_generation` on images endpoints when `chat` mode is enabled.
- Modified OpenAI image handlers (`ImagesGenerations`, `ImagesEdits`) to respect tri-state logic.
- Added unit tests for `DisableImageGenerationMode` behavior and endpoint-specific handling.
- Enhanced configuration diff logging to support `DisableImageGenerationMode`.

internal/api/server.go

@@ -1014,7 +1014,7 @@ func (s *Server) UpdateClients(cfg *config.Config) {
 	}
 
 	if oldCfg != nil && oldCfg.DisableImageGeneration != cfg.DisableImageGeneration {
-		log.Infof("disable-image-generation updated: %t -> %t", oldCfg.DisableImageGeneration, cfg.DisableImageGeneration)
+		log.Infof("disable-image-generation updated: %v -> %v", oldCfg.DisableImageGeneration, cfg.DisableImageGeneration)
 	}
 
 	applySignatureCacheConfig(oldCfg, cfg)

internal/config/config.go

@@ -610,7 +610,7 @@ func LoadConfigOptional(configFile string, optional bool) (*Config, error) {
 	cfg.ErrorLogsMaxFiles = 10
 	cfg.UsageStatisticsEnabled = false
 	cfg.DisableCooling = false
-	cfg.DisableImageGeneration = false
+	cfg.DisableImageGeneration = DisableImageGenerationOff
 	cfg.Pprof.Enable = false
 	cfg.Pprof.Addr = DefaultPprofAddr
 	cfg.AmpCode.RestrictManagementToLocalhost = false // Default to false: API key auth is sufficient

internal/config/disable_image_generation_mode.go

@@ -0,0 +1,136 @@
+package config
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"gopkg.in/yaml.v3"
+)
+
+// DisableImageGenerationMode is a tri-state config value for disable-image-generation.
+//
+// It supports:
+//   - false: enabled
+//   - true: disabled everywhere (including /v1/images/* endpoints)
+//   - "chat": disabled for all non-images endpoints, but enabled for /v1/images/generations and /v1/images/edits
+type DisableImageGenerationMode int
+
+const (
+	DisableImageGenerationOff DisableImageGenerationMode = iota
+	DisableImageGenerationAll
+	DisableImageGenerationChat
+)
+
+func (m DisableImageGenerationMode) String() string {
+	switch m {
+	case DisableImageGenerationOff:
+		return "false"
+	case DisableImageGenerationAll:
+		return "true"
+	case DisableImageGenerationChat:
+		return "chat"
+	default:
+		return "false"
+	}
+}
+
+func (m DisableImageGenerationMode) MarshalYAML() (any, error) {
+	switch m {
+	case DisableImageGenerationAll:
+		return true, nil
+	case DisableImageGenerationChat:
+		return "chat", nil
+	default:
+		return false, nil
+	}
+}
+
+func (m *DisableImageGenerationMode) UnmarshalYAML(value *yaml.Node) error {
+	mode, err := parseDisableImageGenerationNode(value)
+	if err != nil {
+		return err
+	}
+	*m = mode
+	return nil
+}
+
+func (m DisableImageGenerationMode) MarshalJSON() ([]byte, error) {
+	switch m {
+	case DisableImageGenerationAll:
+		return []byte("true"), nil
+	case DisableImageGenerationChat:
+		return json.Marshal("chat")
+	default:
+		return []byte("false"), nil
+	}
+}
+
+func (m *DisableImageGenerationMode) UnmarshalJSON(data []byte) error {
+	mode, err := parseDisableImageGenerationJSON(data)
+	if err != nil {
+		return err
+	}
+	*m = mode
+	return nil
+}
+
+func parseDisableImageGenerationNode(value *yaml.Node) (DisableImageGenerationMode, error) {
+	if value == nil {
+		return DisableImageGenerationOff, nil
+	}
+
+	// First try a typed bool decode (covers unquoted true/false and YAML 1.1 bools).
+	var b bool
+	if err := value.Decode(&b); err == nil && value.Kind == yaml.ScalarNode && value.ShortTag() == "!!bool" {
+		if b {
+			return DisableImageGenerationAll, nil
+		}
+		return DisableImageGenerationOff, nil
+	}
+
+	// Fall back to string decoding (covers quoted "true"/"false" and "chat").
+	var s string
+	if err := value.Decode(&s); err != nil {
+		return DisableImageGenerationOff, fmt.Errorf("invalid disable-image-generation value")
+	}
+	return parseDisableImageGenerationString(s)
+}
+
+func parseDisableImageGenerationJSON(data []byte) (DisableImageGenerationMode, error) {
+	trimmed := bytes.TrimSpace(data)
+	if len(trimmed) == 0 || bytes.Equal(trimmed, []byte("null")) {
+		return DisableImageGenerationOff, nil
+	}
+
+	// bool
+	var b bool
+	if err := json.Unmarshal(trimmed, &b); err == nil {
+		if b {
+			return DisableImageGenerationAll, nil
+		}
+		return DisableImageGenerationOff, nil
+	}
+
+	// string
+	var s string
+	if err := json.Unmarshal(trimmed, &s); err != nil {
+		return DisableImageGenerationOff, fmt.Errorf("invalid disable-image-generation value")
+	}
+	return parseDisableImageGenerationString(s)
+}
+
+func parseDisableImageGenerationString(s string) (DisableImageGenerationMode, error) {
+	s = strings.TrimSpace(strings.ToLower(s))
+	switch s {
+	case "", "false", "0", "off", "no":
+		return DisableImageGenerationOff, nil
+	case "true", "1", "on", "yes":
+		return DisableImageGenerationAll, nil
+	case "chat":
+		return DisableImageGenerationChat, nil
+	default:
+		return DisableImageGenerationOff, fmt.Errorf("invalid disable-image-generation value %q (allowed: true, false, chat)", s)
+	}
+}

internal/config/disable_image_generation_mode_test.go

@@ -0,0 +1,76 @@
+package config
+
+import (
+	"encoding/json"
+	"testing"
+
+	"gopkg.in/yaml.v3"
+)
+
+func TestDisableImageGenerationMode_UnmarshalYAML(t *testing.T) {
+	type wrapper struct {
+		V DisableImageGenerationMode `yaml:"disable-image-generation"`
+	}
+
+	{
+		var w wrapper
+		if err := yaml.Unmarshal([]byte("disable-image-generation: false\n"), &w); err != nil {
+			t.Fatalf("unmarshal false: %v", err)
+		}
+		if w.V != DisableImageGenerationOff {
+			t.Fatalf("false => %v, want %v", w.V, DisableImageGenerationOff)
+		}
+	}
+
+	{
+		var w wrapper
+		if err := yaml.Unmarshal([]byte("disable-image-generation: true\n"), &w); err != nil {
+			t.Fatalf("unmarshal true: %v", err)
+		}
+		if w.V != DisableImageGenerationAll {
+			t.Fatalf("true => %v, want %v", w.V, DisableImageGenerationAll)
+		}
+	}
+
+	{
+		var w wrapper
+		if err := yaml.Unmarshal([]byte("disable-image-generation: chat\n"), &w); err != nil {
+			t.Fatalf("unmarshal chat: %v", err)
+		}
+		if w.V != DisableImageGenerationChat {
+			t.Fatalf("chat => %v, want %v", w.V, DisableImageGenerationChat)
+		}
+	}
+}
+
+func TestDisableImageGenerationMode_UnmarshalJSON(t *testing.T) {
+	{
+		var v DisableImageGenerationMode
+		if err := json.Unmarshal([]byte("false"), &v); err != nil {
+			t.Fatalf("unmarshal false: %v", err)
+		}
+		if v != DisableImageGenerationOff {
+			t.Fatalf("false => %v, want %v", v, DisableImageGenerationOff)
+		}
+	}
+
+	{
+		var v DisableImageGenerationMode
+		if err := json.Unmarshal([]byte("true"), &v); err != nil {
+			t.Fatalf("unmarshal true: %v", err)
+		}
+		if v != DisableImageGenerationAll {
+			t.Fatalf("true => %v, want %v", v, DisableImageGenerationAll)
+		}
+	}
+
+	{
+		var v DisableImageGenerationMode
+		if err := json.Unmarshal([]byte(`"chat"`), &v); err != nil {
+			t.Fatalf("unmarshal chat: %v", err)
+		}
+		if v != DisableImageGenerationChat {
+			t.Fatalf("chat => %v, want %v", v, DisableImageGenerationChat)
+		}
+	}
+}

internal/config/sdk_config.go

@@ -9,11 +9,15 @@ type SDKConfig struct {
 	// ProxyURL is the URL of an optional proxy server to use for outbound requests.
 	ProxyURL string `yaml:"proxy-url" json:"proxy-url"`
 
-	// DisableImageGeneration disables the built-in image_generation tool when true.
-	// When enabled, the server will avoid injecting image_generation into request payloads,
-	// will remove any existing image_generation tool entries from tools arrays, and will
-	// return 404 for /v1/images/generations and /v1/images/edits.
-	DisableImageGeneration bool `yaml:"disable-image-generation" json:"disable-image-generation"`
+	// DisableImageGeneration controls whether the built-in image_generation tool is injected/allowed.
+	//
+	// Supported values:
+	//   - false (default): image_generation is enabled everywhere (normal behavior).
+	//   - true: image_generation is disabled everywhere. The server stops injecting it, removes it from request payloads,
+	//     and returns 404 for /v1/images/generations and /v1/images/edits.
+	//   - "chat": disable image_generation injection for all non-images endpoints (e.g. /v1/responses, /v1/chat/completions),
+	//     while keeping /v1/images/generations and /v1/images/edits enabled and preserving image_generation there.
+	DisableImageGeneration DisableImageGenerationMode `yaml:"disable-image-generation" json:"disable-image-generation"`
 
 	// EnableGeminiCLIEndpoint controls whether Gemini CLI internal endpoints (/v1internal:*) are enabled.
 	// Default is false for safety; when false, /v1internal:* requests are rejected.

internal/runtime/executor/aistudio_executor.go

@@ -428,7 +428,8 @@ func (e *AIStudioExecutor) translateRequest(req cliproxyexecutor.Request, opts c
 	}
 	payload = fixGeminiImageAspectRatio(baseModel, payload)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	payload = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", payload, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	payload = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", payload, originalTranslated, requestedModel, requestPath)
 	payload, _ = sjson.DeleteBytes(payload, "generationConfig.maxOutputTokens")
 	payload, _ = sjson.DeleteBytes(payload, "generationConfig.responseMimeType")
 	payload, _ = sjson.DeleteBytes(payload, "generationConfig.responseJsonSchema")

internal/runtime/executor/antigravity_executor.go

@@ -521,7 +521,8 @@ func (e *AntigravityExecutor) Execute(ctx context.Context, auth *cliproxyauth.Au
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel, requestPath)
 
 	useCredits := cliproxyauth.AntigravityCreditsRequested(ctx) && antigravityCreditsRetryEnabled(e.cfg)
 
@@ -718,7 +719,8 @@ func (e *AntigravityExecutor) executeClaudeNonStream(ctx context.Context, auth *
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel, requestPath)
 
 	useCredits := cliproxyauth.AntigravityCreditsRequested(ctx) && antigravityCreditsRetryEnabled(e.cfg)
 
@@ -1178,7 +1180,8 @@ func (e *AntigravityExecutor) ExecuteStream(ctx context.Context, auth *cliproxya
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "antigravity", "request", translated, originalTranslated, requestedModel, requestPath)
 
 	useCredits := cliproxyauth.AntigravityCreditsRequested(ctx) && antigravityCreditsRetryEnabled(e.cfg)
 

internal/runtime/executor/claude_executor.go

@@ -164,7 +164,8 @@ func (e *ClaudeExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, r
 	body = applyCloaking(ctx, e.cfg, auth, body, baseModel, apiKey)
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body = ensureModelMaxTokens(body, baseModel)
 
 	// Disable thinking if tool_choice forces tool use (Anthropic API constraint)
@@ -349,7 +350,8 @@ func (e *ClaudeExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.A
 	body = applyCloaking(ctx, e.cfg, auth, body, baseModel, apiKey)
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body = ensureModelMaxTokens(body, baseModel)
 
 	// Disable thinking if tool_choice forces tool use (Anthropic API constraint)

internal/runtime/executor/codex_executor.go

@@ -173,7 +173,8 @@ func (e *CodexExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, re
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 	body, _ = sjson.SetBytes(body, "stream", true)
 	body, _ = sjson.DeleteBytes(body, "previous_response_id")
@@ -181,7 +182,7 @@ func (e *CodexExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, re
 	body, _ = sjson.DeleteBytes(body, "safety_identifier")
 	body, _ = sjson.DeleteBytes(body, "stream_options")
 	body = normalizeCodexInstructions(body)
-	if e.cfg == nil || !e.cfg.DisableImageGeneration {
+	if e.cfg == nil || e.cfg.DisableImageGeneration == config.DisableImageGenerationOff {
 		body = ensureImageGenerationTool(body, baseModel, auth)
 	}
 
@@ -327,11 +328,12 @@ func (e *CodexExecutor) executeCompact(ctx context.Context, auth *cliproxyauth.A
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 	body, _ = sjson.DeleteBytes(body, "stream")
 	body = normalizeCodexInstructions(body)
-	if e.cfg == nil || !e.cfg.DisableImageGeneration {
+	if e.cfg == nil || e.cfg.DisableImageGeneration == config.DisableImageGenerationOff {
 		body = ensureImageGenerationTool(body, baseModel, auth)
 	}
 
@@ -421,14 +423,15 @@ func (e *CodexExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Au
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.DeleteBytes(body, "previous_response_id")
 	body, _ = sjson.DeleteBytes(body, "prompt_cache_retention")
 	body, _ = sjson.DeleteBytes(body, "safety_identifier")
 	body, _ = sjson.DeleteBytes(body, "stream_options")
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 	body = normalizeCodexInstructions(body)
-	if e.cfg == nil || !e.cfg.DisableImageGeneration {
+	if e.cfg == nil || e.cfg.DisableImageGeneration == config.DisableImageGenerationOff {
 		body = ensureImageGenerationTool(body, baseModel, auth)
 	}
 

internal/runtime/executor/codex_websockets_executor.go

@@ -184,14 +184,16 @@ func (e *CodexWebsocketsExecutor) Execute(ctx context.Context, auth *cliproxyaut
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 	body, _ = sjson.SetBytes(body, "stream", true)
 	body, _ = sjson.DeleteBytes(body, "previous_response_id")
 	body, _ = sjson.DeleteBytes(body, "prompt_cache_retention")
 	body, _ = sjson.DeleteBytes(body, "safety_identifier")
-	if !gjson.GetBytes(body, "instructions").Exists() {
-		body, _ = sjson.SetBytes(body, "instructions", "")
+	body = normalizeCodexInstructions(body)
+	if e.cfg == nil || e.cfg.DisableImageGeneration == config.DisableImageGenerationOff {
+		body = ensureImageGenerationTool(body, baseModel, auth)
 	}
 
 	httpURL := strings.TrimSuffix(baseURL, "/") + "/responses"
@@ -387,7 +389,12 @@ func (e *CodexWebsocketsExecutor) ExecuteStream(ctx context.Context, auth *clipr
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, body, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, body, requestedModel, requestPath)
+	body = normalizeCodexInstructions(body)
+	if e.cfg == nil || e.cfg.DisableImageGeneration == config.DisableImageGenerationOff {
+		body = ensureImageGenerationTool(body, baseModel, auth)
+	}
 
 	httpURL := strings.TrimSuffix(baseURL, "/") + "/responses"
 	wsURL, err := buildCodexResponsesWebsocketURL(httpURL)

internal/runtime/executor/gemini_cli_executor.go

@@ -139,7 +139,8 @@ func (e *GeminiCLIExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth
 
 	basePayload = fixGeminiCLIImageAspectRatio(baseModel, basePayload)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	basePayload = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "gemini", "request", basePayload, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	basePayload = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "gemini", "request", basePayload, originalTranslated, requestedModel, requestPath)
 
 	action := "generateContent"
 	if req.Metadata != nil {
@@ -294,7 +295,8 @@ func (e *GeminiCLIExecutor) ExecuteStream(ctx context.Context, auth *cliproxyaut
 
 	basePayload = fixGeminiCLIImageAspectRatio(baseModel, basePayload)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	basePayload = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "gemini", "request", basePayload, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	basePayload = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, "gemini", "request", basePayload, originalTranslated, requestedModel, requestPath)
 
 	projectID := resolveGeminiProjectID(auth)
 

internal/runtime/executor/gemini_executor.go

@@ -132,7 +132,8 @@ func (e *GeminiExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, r
 
 	body = fixGeminiImageAspectRatio(baseModel, body)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 
 	action := "generateContent"
@@ -239,7 +240,8 @@ func (e *GeminiExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.A
 
 	body = fixGeminiImageAspectRatio(baseModel, body)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 
 	baseURL := resolveGeminiBaseURL(auth)

internal/runtime/executor/gemini_vertex_executor.go

@@ -335,7 +335,8 @@ func (e *GeminiVertexExecutor) executeWithServiceAccount(ctx context.Context, au
 
 		body = fixGeminiImageAspectRatio(baseModel, body)
 		requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-		body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+		requestPath := helps.PayloadRequestPath(opts)
+		body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 		body, _ = sjson.SetBytes(body, "model", baseModel)
 	}
 
@@ -455,7 +456,8 @@ func (e *GeminiVertexExecutor) executeWithAPIKey(ctx context.Context, auth *clip
 
 	body = fixGeminiImageAspectRatio(baseModel, body)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 
 	action := getVertexAction(baseModel, false)
@@ -565,7 +567,8 @@ func (e *GeminiVertexExecutor) executeStreamWithServiceAccount(ctx context.Conte
 
 	body = fixGeminiImageAspectRatio(baseModel, body)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 
 	action := getVertexAction(baseModel, true)
@@ -694,7 +697,8 @@ func (e *GeminiVertexExecutor) executeStreamWithAPIKey(ctx context.Context, auth
 
 	body = fixGeminiImageAspectRatio(baseModel, body)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, _ = sjson.SetBytes(body, "model", baseModel)
 
 	action := getVertexAction(baseModel, true)

internal/runtime/executor/helps/payload_helpers.go

@@ -16,7 +16,8 @@ import (
 // and restricts matches to the given protocol when supplied. Defaults are checked
 // against the original payload when provided. requestedModel carries the client-visible
 // model name before alias resolution so payload rules can target aliases precisely.
-func ApplyPayloadConfigWithRoot(cfg *config.Config, model, protocol, root string, payload, original []byte, requestedModel string) []byte {
+// requestPath is the inbound HTTP request path (when available) used for endpoint-scoped gates.
+func ApplyPayloadConfigWithRoot(cfg *config.Config, model, protocol, root string, payload, original []byte, requestedModel string, requestPath string) []byte {
 	if cfg == nil || len(payload) == 0 {
 		return payload
 	}
@@ -149,13 +150,34 @@ func ApplyPayloadConfigWithRoot(cfg *config.Config, model, protocol, root string
 		}
 	}
 
-	if cfg.DisableImageGeneration {
+	if cfg.DisableImageGeneration != config.DisableImageGenerationOff {
+		if cfg.DisableImageGeneration == config.DisableImageGenerationChat && isImagesEndpointRequestPath(requestPath) {
+			return out
+		}
 		out = removeToolTypeFromPayloadWithRoot(out, root, "image_generation")
 		out = removeToolChoiceFromPayloadWithRoot(out, root, "image_generation")
 	}
 	return out
 }
 
+func isImagesEndpointRequestPath(path string) bool {
+	path = strings.TrimSpace(path)
+	if path == "" {
+		return false
+	}
+	if path == "/v1/images/generations" || path == "/v1/images/edits" {
+		return true
+	}
+	// Be tolerant of prefix routers that may report a longer matched route.
+	if strings.HasSuffix(path, "/v1/images/generations") || strings.HasSuffix(path, "/v1/images/edits") {
+		return true
+	}
+	if strings.HasSuffix(path, "/images/generations") || strings.HasSuffix(path, "/images/edits") {
+		return true
+	}
+	return false
+}
+
 func payloadModelRulesMatch(rules []config.PayloadModelRule, protocol string, models []string) bool {
 	if len(rules) == 0 || len(models) == 0 {
 		return false
@@ -367,6 +389,24 @@ func PayloadRequestedModel(opts cliproxyexecutor.Options, fallback string) strin
 	}
 }
 
+func PayloadRequestPath(opts cliproxyexecutor.Options) string {
+	if len(opts.Metadata) == 0 {
+		return ""
+	}
+	raw, ok := opts.Metadata[cliproxyexecutor.RequestPathMetadataKey]
+	if !ok || raw == nil {
+		return ""
+	}
+	switch v := raw.(type) {
+	case string:
+		return strings.TrimSpace(v)
+	case []byte:
+		return strings.TrimSpace(string(v))
+	default:
+		return ""
+	}
+}
+
 // matchModelPattern performs simple wildcard matching where '*' matches zero or more characters.
 // Examples:
 //

internal/runtime/executor/helps/payload_helpers_disable_image_generation_test.go

@@ -9,11 +9,11 @@ import (
 
 func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolsEntry(t *testing.T) {
 	cfg := &config.Config{
-		SDKConfig: config.SDKConfig{DisableImageGeneration: true},
+		SDKConfig: config.SDKConfig{DisableImageGeneration: config.DisableImageGenerationAll},
 	}
 	payload := []byte(`{"tools":[{"type":"image_generation","output_format":"png"},{"type":"function","name":"f1"}]}`)
 
-	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "openai-response", "", payload, nil, "")
+	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "openai-response", "", payload, nil, "", "")
 
 	tools := gjson.GetBytes(out, "tools")
 	if !tools.Exists() || !tools.IsArray() {
@@ -30,11 +30,11 @@ func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolsEntry(t *
 
 func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolsEntryWithRoot(t *testing.T) {
 	cfg := &config.Config{
-		SDKConfig: config.SDKConfig{DisableImageGeneration: true},
+		SDKConfig: config.SDKConfig{DisableImageGeneration: config.DisableImageGenerationAll},
 	}
 	payload := []byte(`{"request":{"tools":[{"type":"image_generation"},{"type":"web_search"}]}}`)
 
-	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "gemini-cli", "request", payload, nil, "")
+	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "gemini-cli", "request", payload, nil, "", "")
 
 	tools := gjson.GetBytes(out, "request.tools")
 	if !tools.Exists() || !tools.IsArray() {
@@ -51,11 +51,11 @@ func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolsEntryWith
 
 func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolChoiceByType(t *testing.T) {
 	cfg := &config.Config{
-		SDKConfig: config.SDKConfig{DisableImageGeneration: true},
+		SDKConfig: config.SDKConfig{DisableImageGeneration: config.DisableImageGenerationAll},
 	}
 	payload := []byte(`{"tools":[{"type":"image_generation"},{"type":"function","name":"f1"}],"tool_choice":{"type":"image_generation"}}`)
 
-	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "openai-response", "", payload, nil, "")
+	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "openai-response", "", payload, nil, "", "")
 
 	if gjson.GetBytes(out, "tool_choice").Exists() {
 		t.Fatalf("expected tool_choice to be removed")
@@ -64,13 +64,34 @@ func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolChoiceByTy
 
 func TestApplyPayloadConfigWithRoot_DisableImageGeneration_RemovesToolChoiceByNameWithRoot(t *testing.T) {
 	cfg := &config.Config{
-		SDKConfig: config.SDKConfig{DisableImageGeneration: true},
+		SDKConfig: config.SDKConfig{DisableImageGeneration: config.DisableImageGenerationAll},
 	}
 	payload := []byte(`{"request":{"tools":[{"type":"image_generation"},{"type":"web_search"}],"tool_choice":{"type":"tool","name":"image_generation"}}}`)
 
-	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "gemini-cli", "request", payload, nil, "")
+	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "gemini-cli", "request", payload, nil, "", "")
 
 	if gjson.GetBytes(out, "request.tool_choice").Exists() {
 		t.Fatalf("expected request.tool_choice to be removed")
 	}
 }
+
+func TestApplyPayloadConfigWithRoot_DisableImageGenerationChat_KeepsImageGenerationOnImagesEndpoints(t *testing.T) {
+	cfg := &config.Config{
+		SDKConfig: config.SDKConfig{DisableImageGeneration: config.DisableImageGenerationChat},
+	}
+	payload := []byte(`{"tools":[{"type":"image_generation"},{"type":"function","name":"f1"}],"tool_choice":{"type":"image_generation"}}`)
+
+	out := ApplyPayloadConfigWithRoot(cfg, "gpt-5.4", "openai-response", "", payload, nil, "", "/v1/images/generations")
+
+	tools := gjson.GetBytes(out, "tools")
+	if !tools.Exists() || !tools.IsArray() {
+		t.Fatalf("expected tools array, got %v", tools.Type)
+	}
+	arr := tools.Array()
+	if len(arr) != 2 {
+		t.Fatalf("expected 2 tools (no removal), got %d", len(arr))
+	}
+	if !gjson.GetBytes(out, "tool_choice").Exists() {
+		t.Fatalf("expected tool_choice to be kept on images endpoint")
+	}
+}

internal/runtime/executor/kimi_executor.go

@@ -108,7 +108,8 @@ func (e *KimiExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, req
 	}
 
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, err = normalizeKimiToolMessageLinks(body)
 	if err != nil {
 		return resp, err
@@ -217,7 +218,8 @@ func (e *KimiExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Aut
 		return nil, fmt.Errorf("kimi executor: failed to set stream_options in payload: %w", err)
 	}
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	body = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", body, originalTranslated, requestedModel, requestPath)
 	body, err = normalizeKimiToolMessageLinks(body)
 	if err != nil {
 		return nil, err

internal/runtime/executor/openai_compat_executor.go

@@ -97,7 +97,8 @@ func (e *OpenAICompatExecutor) Execute(ctx context.Context, auth *cliproxyauth.A
 	originalTranslated := sdktranslator.TranslateRequest(from, to, baseModel, originalPayload, opts.Stream)
 	translated := sdktranslator.TranslateRequest(from, to, baseModel, req.Payload, opts.Stream)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", translated, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", translated, originalTranslated, requestedModel, requestPath)
 	if opts.Alt == "responses/compact" {
 		if updated, errDelete := sjson.DeleteBytes(translated, "stream"); errDelete == nil {
 			translated = updated
@@ -199,7 +200,8 @@ func (e *OpenAICompatExecutor) ExecuteStream(ctx context.Context, auth *cliproxy
 	originalTranslated := sdktranslator.TranslateRequest(from, to, baseModel, originalPayload, true)
 	translated := sdktranslator.TranslateRequest(from, to, baseModel, req.Payload, true)
 	requestedModel := helps.PayloadRequestedModel(opts, req.Model)
-	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", translated, originalTranslated, requestedModel)
+	requestPath := helps.PayloadRequestPath(opts)
+	translated = helps.ApplyPayloadConfigWithRoot(e.cfg, baseModel, to.String(), "", translated, originalTranslated, requestedModel, requestPath)
 
 	translated, err = thinking.ApplyThinking(translated, req.Model, from.String(), to.String(), e.Identifier())
 	if err != nil {

internal/watcher/diff/config_diff.go

@@ -43,7 +43,7 @@ func BuildConfigChangeDetails(oldCfg, newCfg *config.Config) []string {
 		changes = append(changes, fmt.Sprintf("disable-cooling: %t -> %t", oldCfg.DisableCooling, newCfg.DisableCooling))
 	}
 	if oldCfg.DisableImageGeneration != newCfg.DisableImageGeneration {
-		changes = append(changes, fmt.Sprintf("disable-image-generation: %t -> %t", oldCfg.DisableImageGeneration, newCfg.DisableImageGeneration))
+		changes = append(changes, fmt.Sprintf("disable-image-generation: %v -> %v", oldCfg.DisableImageGeneration, newCfg.DisableImageGeneration))
 	}
 	if oldCfg.RequestLog != newCfg.RequestLog {
 		changes = append(changes, fmt.Sprintf("request-log: %t -> %t", oldCfg.RequestLog, newCfg.RequestLog))

internal/watcher/diff/config_diff_test.go

@@ -279,7 +279,7 @@ func TestBuildConfigChangeDetails_FlagsAndKeys(t *testing.T) {
 			APIKeys:                    []string{" key-1 ", "key-2"},
 			ForceModelPrefix:           true,
 			NonStreamKeepAliveInterval: 5,
-			DisableImageGeneration:     true,
+			DisableImageGeneration:     config.DisableImageGenerationAll,
 		},
 	}
 
@@ -408,7 +408,7 @@ func TestBuildConfigChangeDetails_AllBranches(t *testing.T) {
 			RequestLog:             true,
 			ProxyURL:               "http://new-proxy",
 			APIKeys:                []string{"keyB"},
-			DisableImageGeneration: true,
+			DisableImageGeneration: config.DisableImageGenerationAll,
 		},
 		OAuthExcludedModels: map[string][]string{"p1": {"b", "c"}, "p2": {"d"}},
 		OpenAICompatibility: []config.OpenAICompatibility{