feat(models): add hardcoded GPT-Image-2 model support in Codex

- Added `GPT-Image-2` as a built-in model to avoid dependency on remote updates for Codex.
- Updated model tier functions (`CodexFree`, `CodexTeam`, etc.) to include built-in models via `WithCodexBuiltins`.
- Introduced new handlers for image generation and edit operations under `OpenAIAPIHandler`.
- Extended tests to validate 503 response for unsupported image model requests.

internal/api/server.go

@@ -344,6 +344,8 @@ func (s *Server) setupRoutes() {
 		v1.GET("/models", s.unifiedModelsHandler(openaiHandlers, claudeCodeHandlers))
 		v1.POST("/chat/completions", openaiHandlers.ChatCompletions)
 		v1.POST("/completions", openaiHandlers.Completions)
+		v1.POST("/images/generations", openaiHandlers.ImagesGenerations)
+		v1.POST("/images/edits", openaiHandlers.ImagesEdits)
 		v1.POST("/messages", claudeCodeHandlers.ClaudeMessages)
 		v1.POST("/messages/count_tokens", claudeCodeHandlers.ClaudeCountTokens)
 		v1.GET("/responses", openaiResponsesHandlers.ResponsesWebsocket)

internal/registry/model_definitions.go

@@ -6,6 +6,8 @@ import (
 	"strings"
 )
 
+const codexBuiltinImageModelID = "gpt-image-2"
+
 // staticModelsJSON mirrors the top-level structure of models.json.
 type staticModelsJSON struct {
 	Claude      []*ModelInfo `json:"claude"`
@@ -48,22 +50,22 @@ func GetAIStudioModels() []*ModelInfo {
 
 // GetCodexFreeModels returns model definitions for the Codex free plan tier.
 func GetCodexFreeModels() []*ModelInfo {
-	return cloneModelInfos(getModels().CodexFree)
+	return WithCodexBuiltins(cloneModelInfos(getModels().CodexFree))
 }
 
 // GetCodexTeamModels returns model definitions for the Codex team plan tier.
 func GetCodexTeamModels() []*ModelInfo {
-	return cloneModelInfos(getModels().CodexTeam)
+	return WithCodexBuiltins(cloneModelInfos(getModels().CodexTeam))
 }
 
 // GetCodexPlusModels returns model definitions for the Codex plus plan tier.
 func GetCodexPlusModels() []*ModelInfo {
-	return cloneModelInfos(getModels().CodexPlus)
+	return WithCodexBuiltins(cloneModelInfos(getModels().CodexPlus))
 }
 
 // GetCodexProModels returns model definitions for the Codex pro plan tier.
 func GetCodexProModels() []*ModelInfo {
-	return cloneModelInfos(getModels().CodexPro)
+	return WithCodexBuiltins(cloneModelInfos(getModels().CodexPro))
 }
 
 // GetKimiModels returns the standard Kimi (Moonshot AI) model definitions.
@@ -76,6 +78,71 @@ func GetAntigravityModels() []*ModelInfo {
 	return cloneModelInfos(getModels().Antigravity)
 }
 
+// WithCodexBuiltins injects hard-coded Codex-only model definitions that should
+// not depend on remote models.json updates. Built-ins replace any matching IDs
+// already present in the provided slice.
+func WithCodexBuiltins(models []*ModelInfo) []*ModelInfo {
+	return upsertModelInfos(models, codexBuiltinImageModelInfo())
+}
+
+func codexBuiltinImageModelInfo() *ModelInfo {
+	return &ModelInfo{
+		ID:          codexBuiltinImageModelID,
+		Object:      "model",
+		Created:     1704067200, // 2024-01-01
+		OwnedBy:     "openai",
+		Type:        "openai",
+		DisplayName: "GPT Image 2",
+		Version:     codexBuiltinImageModelID,
+	}
+}
+
+func upsertModelInfos(models []*ModelInfo, extras ...*ModelInfo) []*ModelInfo {
+	if len(extras) == 0 {
+		return models
+	}
+
+	extraIDs := make(map[string]struct{}, len(extras))
+	extraList := make([]*ModelInfo, 0, len(extras))
+	for _, extra := range extras {
+		if extra == nil {
+			continue
+		}
+		id := strings.TrimSpace(extra.ID)
+		if id == "" {
+			continue
+		}
+		key := strings.ToLower(id)
+		if _, exists := extraIDs[key]; exists {
+			continue
+		}
+		extraIDs[key] = struct{}{}
+		extraList = append(extraList, cloneModelInfo(extra))
+	}
+
+	if len(extraList) == 0 {
+		return models
+	}
+
+	filtered := make([]*ModelInfo, 0, len(models)+len(extraList))
+	for _, model := range models {
+		if model == nil {
+			continue
+		}
+		id := strings.TrimSpace(model.ID)
+		if id == "" {
+			continue
+		}
+		if _, exists := extraIDs[strings.ToLower(id)]; exists {
+			continue
+		}
+		filtered = append(filtered, model)
+	}
+
+	filtered = append(filtered, extraList...)
+	return filtered
+}
+
 // cloneModelInfos returns a shallow copy of the slice with each element deep-cloned.
 func cloneModelInfos(models []*ModelInfo) []*ModelInfo {
 	if len(models) == 0 {

sdk/api/handlers/handlers.go

@@ -795,6 +795,13 @@ func (h *BaseAPIHandler) getRequestDetails(modelName string) (providers []string
 	parsed := thinking.ParseSuffix(resolvedModelName)
 	baseModel := strings.TrimSpace(parsed.ModelName)
 
+	if strings.EqualFold(baseModel, "gpt-image-2") {
+		return nil, "", &interfaces.ErrorMessage{
+			StatusCode: http.StatusServiceUnavailable,
+			Error:      fmt.Errorf("model %s is only supported on /v1/images/generations and /v1/images/edits", baseModel),
+		}
+	}
+
 	providers = util.GetProviderName(baseModel)
 	// Fallback: if baseModel has no provider but differs from resolvedModelName,
 	// try using the full model name. This handles edge cases where custom models

sdk/api/handlers/handlers_request_details_test.go

@@ -1,7 +1,9 @@
 package handlers
 
 import (
+	"net/http"
 	"reflect"
+	"strings"
 	"testing"
 	"time"
 
@@ -116,3 +118,22 @@ func TestGetRequestDetails_PreservesSuffix(t *testing.T) {
 		})
 	}
 }
+
+func TestGetRequestDetails_ImageModelReturns503(t *testing.T) {
+	handler := NewBaseAPIHandlers(&sdkconfig.SDKConfig{}, coreauth.NewManager(nil, nil, nil))
+
+	_, _, errMsg := handler.getRequestDetails("gpt-image-2")
+	if errMsg == nil {
+		t.Fatalf("expected error for gpt-image-2, got nil")
+	}
+	if errMsg.StatusCode != http.StatusServiceUnavailable {
+		t.Fatalf("unexpected status code: got %d want %d", errMsg.StatusCode, http.StatusServiceUnavailable)
+	}
+	if errMsg.Error == nil {
+		t.Fatalf("expected error message, got nil")
+	}
+	msg := errMsg.Error.Error()
+	if !strings.Contains(msg, "/v1/images/generations") || !strings.Contains(msg, "/v1/images/edits") {
+		t.Fatalf("unexpected error message: %q", msg)
+	}
+}

sdk/api/handlers/openai/openai_images_handlers.go

@@ -0,0 +1,904 @@
+package openai
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"mime/multipart"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/interfaces"
+	"github.com/router-for-me/CLIProxyAPI/v6/sdk/api/handlers"
+	log "github.com/sirupsen/logrus"
+	"github.com/tidwall/gjson"
+	"github.com/tidwall/sjson"
+)
+
+const (
+	defaultImagesMainModel = "gpt-5.4-mini"
+	defaultImagesToolModel = "gpt-image-2"
+)
+
+type imageCallResult struct {
+	Result        string
+	RevisedPrompt string
+	OutputFormat  string
+	Size          string
+	Background    string
+	Quality       string
+}
+
+type sseFrameAccumulator struct {
+	pending []byte
+}
+
+func (a *sseFrameAccumulator) AddChunk(chunk []byte) [][]byte {
+	if len(chunk) == 0 {
+		return nil
+	}
+
+	if responsesSSENeedsLineBreak(a.pending, chunk) {
+		a.pending = append(a.pending, '\n')
+	}
+	a.pending = append(a.pending, chunk...)
+
+	var frames [][]byte
+	for {
+		frameLen := responsesSSEFrameLen(a.pending)
+		if frameLen == 0 {
+			break
+		}
+		frames = append(frames, a.pending[:frameLen])
+		copy(a.pending, a.pending[frameLen:])
+		a.pending = a.pending[:len(a.pending)-frameLen]
+	}
+
+	if len(bytes.TrimSpace(a.pending)) == 0 {
+		a.pending = a.pending[:0]
+		return frames
+	}
+	if len(a.pending) == 0 || !responsesSSECanEmitWithoutDelimiter(a.pending) {
+		return frames
+	}
+	frames = append(frames, a.pending)
+	a.pending = a.pending[:0]
+	return frames
+}
+
+func (a *sseFrameAccumulator) Flush() [][]byte {
+	if len(a.pending) == 0 {
+		return nil
+	}
+
+	var frames [][]byte
+	for {
+		frameLen := responsesSSEFrameLen(a.pending)
+		if frameLen == 0 {
+			break
+		}
+		frames = append(frames, a.pending[:frameLen])
+		copy(a.pending, a.pending[frameLen:])
+		a.pending = a.pending[:len(a.pending)-frameLen]
+	}
+
+	if len(bytes.TrimSpace(a.pending)) == 0 {
+		a.pending = nil
+		return frames
+	}
+	if responsesSSECanEmitWithoutDelimiter(a.pending) {
+		frames = append(frames, a.pending)
+	}
+	a.pending = nil
+	return frames
+}
+
+func mimeTypeFromOutputFormat(outputFormat string) string {
+	if outputFormat == "" {
+		return "image/png"
+	}
+	if strings.Contains(outputFormat, "/") {
+		return outputFormat
+	}
+	switch strings.ToLower(strings.TrimSpace(outputFormat)) {
+	case "png":
+		return "image/png"
+	case "jpg", "jpeg":
+		return "image/jpeg"
+	case "webp":
+		return "image/webp"
+	default:
+		return "image/png"
+	}
+}
+
+func multipartFileToDataURL(fileHeader *multipart.FileHeader) (string, error) {
+	if fileHeader == nil {
+		return "", fmt.Errorf("upload file is nil")
+	}
+	f, err := fileHeader.Open()
+	if err != nil {
+		return "", fmt.Errorf("open upload file failed: %w", err)
+	}
+	defer func() {
+		if errClose := f.Close(); errClose != nil {
+			log.Errorf("openai images: close upload file error: %v", errClose)
+		}
+	}()
+
+	data, err := io.ReadAll(f)
+	if err != nil {
+		return "", fmt.Errorf("read upload file failed: %w", err)
+	}
+
+	mediaType := strings.TrimSpace(fileHeader.Header.Get("Content-Type"))
+	if mediaType == "" {
+		mediaType = http.DetectContentType(data)
+	}
+
+	b64 := base64.StdEncoding.EncodeToString(data)
+	return "data:" + mediaType + ";base64," + b64, nil
+}
+
+func parseIntField(raw string, fallback int64) int64 {
+	raw = strings.TrimSpace(raw)
+	if raw == "" {
+		return fallback
+	}
+	v, err := strconv.ParseInt(raw, 10, 64)
+	if err != nil {
+		return fallback
+	}
+	return v
+}
+
+func parseBoolField(raw string, fallback bool) bool {
+	raw = strings.TrimSpace(strings.ToLower(raw))
+	if raw == "" {
+		return fallback
+	}
+	switch raw {
+	case "1", "true", "yes", "on":
+		return true
+	case "0", "false", "no", "off":
+		return false
+	default:
+		return fallback
+	}
+}
+
+func (h *OpenAIAPIHandler) ImagesGenerations(c *gin.Context) {
+	rawJSON, err := c.GetRawData()
+	if err != nil {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: fmt.Sprintf("Invalid request: %v", err),
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+	if !json.Valid(rawJSON) {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: body must be valid JSON",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	prompt := strings.TrimSpace(gjson.GetBytes(rawJSON, "prompt").String())
+	if prompt == "" {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: prompt is required",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	imageModel := strings.TrimSpace(gjson.GetBytes(rawJSON, "model").String())
+	if imageModel == "" {
+		imageModel = defaultImagesToolModel
+	}
+	responseFormat := strings.TrimSpace(gjson.GetBytes(rawJSON, "response_format").String())
+	if responseFormat == "" {
+		responseFormat = "b64_json"
+	}
+	stream := gjson.GetBytes(rawJSON, "stream").Bool()
+
+	tool := []byte(`{"type":"image_generation","action":"generate"}`)
+	tool, _ = sjson.SetBytes(tool, "model", imageModel)
+
+	if v := strings.TrimSpace(gjson.GetBytes(rawJSON, "size").String()); v != "" {
+		tool, _ = sjson.SetBytes(tool, "size", v)
+	}
+	if v := strings.TrimSpace(gjson.GetBytes(rawJSON, "quality").String()); v != "" {
+		tool, _ = sjson.SetBytes(tool, "quality", v)
+	}
+	if v := strings.TrimSpace(gjson.GetBytes(rawJSON, "background").String()); v != "" {
+		tool, _ = sjson.SetBytes(tool, "background", v)
+	}
+	if v := strings.TrimSpace(gjson.GetBytes(rawJSON, "output_format").String()); v != "" {
+		tool, _ = sjson.SetBytes(tool, "output_format", v)
+	}
+	if v := gjson.GetBytes(rawJSON, "output_compression"); v.Exists() {
+		if v.Type == gjson.Number {
+			tool, _ = sjson.SetBytes(tool, "output_compression", v.Int())
+		}
+	}
+	if v := gjson.GetBytes(rawJSON, "partial_images"); v.Exists() {
+		if v.Type == gjson.Number {
+			tool, _ = sjson.SetBytes(tool, "partial_images", v.Int())
+		}
+	}
+	if v := gjson.GetBytes(rawJSON, "n"); v.Exists() {
+		if v.Type == gjson.Number {
+			tool, _ = sjson.SetBytes(tool, "n", v.Int())
+		}
+	}
+	if v := strings.TrimSpace(gjson.GetBytes(rawJSON, "moderation").String()); v != "" {
+		tool, _ = sjson.SetBytes(tool, "moderation", v)
+	}
+
+	responsesReq := buildImagesResponsesRequest(prompt, nil, tool)
+	if stream {
+		h.streamImagesFromResponses(c, responsesReq, responseFormat, "image_generation")
+		return
+	}
+	h.collectImagesFromResponses(c, responsesReq, responseFormat)
+}
+
+func (h *OpenAIAPIHandler) ImagesEdits(c *gin.Context) {
+	contentType := strings.ToLower(strings.TrimSpace(c.GetHeader("Content-Type")))
+	if strings.HasPrefix(contentType, "application/json") {
+		h.imagesEditsFromJSON(c)
+		return
+	}
+	if strings.HasPrefix(contentType, "multipart/form-data") || contentType == "" {
+		h.imagesEditsFromMultipart(c)
+		return
+	}
+
+	c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+		Error: handlers.ErrorDetail{
+			Message: fmt.Sprintf("Invalid request: unsupported Content-Type %q", contentType),
+			Type:    "invalid_request_error",
+		},
+	})
+}
+
+func (h *OpenAIAPIHandler) imagesEditsFromMultipart(c *gin.Context) {
+	form, err := c.MultipartForm()
+	if err != nil {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: fmt.Sprintf("Invalid request: %v", err),
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	prompt := strings.TrimSpace(c.PostForm("prompt"))
+	if prompt == "" {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: prompt is required",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	var imageFiles []*multipart.FileHeader
+	if files := form.File["image[]"]; len(files) > 0 {
+		imageFiles = files
+	} else if files := form.File["image"]; len(files) > 0 {
+		imageFiles = files
+	}
+	if len(imageFiles) == 0 {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: image is required",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	images := make([]string, 0, len(imageFiles))
+	for _, fh := range imageFiles {
+		dataURL, err := multipartFileToDataURL(fh)
+		if err != nil {
+			c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+				Error: handlers.ErrorDetail{
+					Message: fmt.Sprintf("Invalid request: %v", err),
+					Type:    "invalid_request_error",
+				},
+			})
+			return
+		}
+		images = append(images, dataURL)
+	}
+
+	var maskDataURL *string
+	if maskFiles := form.File["mask"]; len(maskFiles) > 0 && maskFiles[0] != nil {
+		dataURL, err := multipartFileToDataURL(maskFiles[0])
+		if err != nil {
+			c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+				Error: handlers.ErrorDetail{
+					Message: fmt.Sprintf("Invalid request: %v", err),
+					Type:    "invalid_request_error",
+				},
+			})
+			return
+		}
+		maskDataURL = &dataURL
+	}
+
+	imageModel := strings.TrimSpace(c.PostForm("model"))
+	if imageModel == "" {
+		imageModel = defaultImagesToolModel
+	}
+	responseFormat := strings.TrimSpace(c.PostForm("response_format"))
+	if responseFormat == "" {
+		responseFormat = "b64_json"
+	}
+	stream := parseBoolField(c.PostForm("stream"), false)
+
+	tool := []byte(`{"type":"image_generation","action":"edit"}`)
+	tool, _ = sjson.SetBytes(tool, "model", imageModel)
+
+	if v := strings.TrimSpace(c.PostForm("size")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "size", v)
+	}
+	if v := strings.TrimSpace(c.PostForm("quality")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "quality", v)
+	}
+	if v := strings.TrimSpace(c.PostForm("background")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "background", v)
+	}
+	if v := strings.TrimSpace(c.PostForm("output_format")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "output_format", v)
+	}
+	if v := strings.TrimSpace(c.PostForm("input_fidelity")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "input_fidelity", v)
+	}
+	if v := strings.TrimSpace(c.PostForm("moderation")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "moderation", v)
+	}
+
+	if v := strings.TrimSpace(c.PostForm("output_compression")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "output_compression", parseIntField(v, 0))
+	}
+	if v := strings.TrimSpace(c.PostForm("partial_images")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "partial_images", parseIntField(v, 0))
+	}
+	if v := strings.TrimSpace(c.PostForm("n")); v != "" {
+		tool, _ = sjson.SetBytes(tool, "n", parseIntField(v, 0))
+	}
+
+	if maskDataURL != nil && strings.TrimSpace(*maskDataURL) != "" {
+		tool, _ = sjson.SetBytes(tool, "input_image_mask.image_url", strings.TrimSpace(*maskDataURL))
+	}
+
+	responsesReq := buildImagesResponsesRequest(prompt, images, tool)
+	if stream {
+		h.streamImagesFromResponses(c, responsesReq, responseFormat, "image_edit")
+		return
+	}
+	h.collectImagesFromResponses(c, responsesReq, responseFormat)
+}
+
+func (h *OpenAIAPIHandler) imagesEditsFromJSON(c *gin.Context) {
+	rawJSON, err := c.GetRawData()
+	if err != nil {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: fmt.Sprintf("Invalid request: %v", err),
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+	if !json.Valid(rawJSON) {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: body must be valid JSON",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	prompt := strings.TrimSpace(gjson.GetBytes(rawJSON, "prompt").String())
+	if prompt == "" {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: prompt is required",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	var images []string
+	imagesResult := gjson.GetBytes(rawJSON, "images")
+	if imagesResult.IsArray() {
+		for _, img := range imagesResult.Array() {
+			url := strings.TrimSpace(img.Get("image_url").String())
+			if url == "" {
+				continue
+			}
+			images = append(images, url)
+		}
+	}
+	if len(images) == 0 {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: images[].image_url is required (file_id is not supported)",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	var maskDataURL *string
+	if mask := gjson.GetBytes(rawJSON, "mask.image_url"); mask.Exists() {
+		url := strings.TrimSpace(mask.String())
+		if url != "" {
+			maskDataURL = &url
+		}
+	} else if mask := gjson.GetBytes(rawJSON, "mask.file_id"); mask.Exists() {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Invalid request: mask.file_id is not supported (use mask.image_url instead)",
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	imageModel := strings.TrimSpace(gjson.GetBytes(rawJSON, "model").String())
+	if imageModel == "" {
+		imageModel = defaultImagesToolModel
+	}
+	responseFormat := strings.TrimSpace(gjson.GetBytes(rawJSON, "response_format").String())
+	if responseFormat == "" {
+		responseFormat = "b64_json"
+	}
+	stream := gjson.GetBytes(rawJSON, "stream").Bool()
+
+	tool := []byte(`{"type":"image_generation","action":"edit"}`)
+	tool, _ = sjson.SetBytes(tool, "model", imageModel)
+
+	for _, field := range []string{"size", "quality", "background", "output_format", "input_fidelity", "moderation"} {
+		if v := strings.TrimSpace(gjson.GetBytes(rawJSON, field).String()); v != "" {
+			tool, _ = sjson.SetBytes(tool, field, v)
+		}
+	}
+
+	for _, field := range []string{"output_compression", "partial_images", "n"} {
+		if v := gjson.GetBytes(rawJSON, field); v.Exists() && v.Type == gjson.Number {
+			tool, _ = sjson.SetBytes(tool, field, v.Int())
+		}
+	}
+
+	if maskDataURL != nil && strings.TrimSpace(*maskDataURL) != "" {
+		tool, _ = sjson.SetBytes(tool, "input_image_mask.image_url", strings.TrimSpace(*maskDataURL))
+	}
+
+	responsesReq := buildImagesResponsesRequest(prompt, images, tool)
+	if stream {
+		h.streamImagesFromResponses(c, responsesReq, responseFormat, "image_edit")
+		return
+	}
+	h.collectImagesFromResponses(c, responsesReq, responseFormat)
+}
+
+func buildImagesResponsesRequest(prompt string, images []string, toolJSON []byte) []byte {
+	req := []byte(`{"instructions":"","stream":true,"reasoning":{"effort":"medium","summary":"auto"},"parallel_tool_calls":true,"include":["reasoning.encrypted_content"],"model":"","store":false,"tool_choice":{"type":"image_generation"}}`)
+	req, _ = sjson.SetBytes(req, "model", defaultImagesMainModel)
+
+	input := []byte(`[{"type":"message","role":"user","content":[{"type":"input_text","text":""}]}]`)
+	input, _ = sjson.SetBytes(input, "0.content.0.text", prompt)
+	contentIndex := 1
+	for _, img := range images {
+		if strings.TrimSpace(img) == "" {
+			continue
+		}
+		part := []byte(`{"type":"input_image","image_url":""}`)
+		part, _ = sjson.SetBytes(part, "image_url", img)
+		path := fmt.Sprintf("0.content.%d", contentIndex)
+		input, _ = sjson.SetRawBytes(input, path, part)
+		contentIndex++
+	}
+	req, _ = sjson.SetRawBytes(req, "input", input)
+
+	req, _ = sjson.SetRawBytes(req, "tools", []byte(`[]`))
+	if len(toolJSON) > 0 && json.Valid(toolJSON) {
+		req, _ = sjson.SetRawBytes(req, "tools.-1", toolJSON)
+	}
+	return req
+}
+
+func (h *OpenAIAPIHandler) collectImagesFromResponses(c *gin.Context, responsesReq []byte, responseFormat string) {
+	c.Header("Content-Type", "application/json")
+
+	cliCtx, cliCancel := h.GetContextWithCancel(h, c, context.Background())
+	stopKeepAlive := h.StartNonStreamingKeepAlive(c, cliCtx)
+
+	dataChan, upstreamHeaders, errChan := h.ExecuteStreamWithAuthManager(cliCtx, "openai-response", defaultImagesMainModel, responsesReq, "")
+
+	out, errMsg := collectImagesFromResponsesStream(cliCtx, dataChan, errChan, responseFormat)
+	stopKeepAlive()
+	if errMsg != nil {
+		h.WriteErrorResponse(c, errMsg)
+		if errMsg.Error != nil {
+			cliCancel(errMsg.Error)
+		} else {
+			cliCancel(nil)
+		}
+		return
+	}
+	handlers.WriteUpstreamHeaders(c.Writer.Header(), upstreamHeaders)
+	_, _ = c.Writer.Write(out)
+	cliCancel()
+}
+
+func collectImagesFromResponsesStream(ctx context.Context, data <-chan []byte, errs <-chan *interfaces.ErrorMessage, responseFormat string) ([]byte, *interfaces.ErrorMessage) {
+	acc := &sseFrameAccumulator{}
+
+	processFrame := func(frame []byte) ([]byte, bool, *interfaces.ErrorMessage) {
+		for _, line := range bytes.Split(frame, []byte("\n")) {
+			trimmed := bytes.TrimSpace(bytes.TrimRight(line, "\r"))
+			if len(trimmed) == 0 {
+				continue
+			}
+			if !bytes.HasPrefix(trimmed, []byte("data:")) {
+				continue
+			}
+			payload := bytes.TrimSpace(trimmed[len("data:"):])
+			if len(payload) == 0 || bytes.Equal(payload, []byte("[DONE]")) {
+				continue
+			}
+			if !json.Valid(payload) {
+				return nil, false, &interfaces.ErrorMessage{StatusCode: http.StatusBadGateway, Error: fmt.Errorf("invalid SSE data JSON")}
+			}
+
+			if gjson.GetBytes(payload, "type").String() != "response.completed" {
+				continue
+			}
+
+			results, createdAt, usageRaw, firstMeta, err := extractImagesFromResponsesCompleted(payload)
+			if err != nil {
+				return nil, false, &interfaces.ErrorMessage{StatusCode: http.StatusBadGateway, Error: err}
+			}
+			if len(results) == 0 {
+				return nil, false, &interfaces.ErrorMessage{StatusCode: http.StatusBadGateway, Error: fmt.Errorf("upstream did not return image output")}
+			}
+			out, err := buildImagesAPIResponse(results, createdAt, usageRaw, firstMeta, responseFormat)
+			if err != nil {
+				return nil, false, &interfaces.ErrorMessage{StatusCode: http.StatusInternalServerError, Error: err}
+			}
+			return out, true, nil
+		}
+		return nil, false, nil
+	}
+
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, &interfaces.ErrorMessage{StatusCode: http.StatusRequestTimeout, Error: ctx.Err()}
+		case errMsg, ok := <-errs:
+			if ok && errMsg != nil {
+				return nil, errMsg
+			}
+			errs = nil
+		case chunk, ok := <-data:
+			if !ok {
+				for _, frame := range acc.Flush() {
+					if out, done, errMsg := processFrame(frame); errMsg != nil {
+						return nil, errMsg
+					} else if done {
+						return out, nil
+					}
+				}
+				return nil, &interfaces.ErrorMessage{StatusCode: http.StatusBadGateway, Error: fmt.Errorf("stream disconnected before completion")}
+			}
+			for _, frame := range acc.AddChunk(chunk) {
+				if out, done, errMsg := processFrame(frame); errMsg != nil {
+					return nil, errMsg
+				} else if done {
+					return out, nil
+				}
+			}
+		}
+	}
+}
+
+func extractImagesFromResponsesCompleted(payload []byte) (results []imageCallResult, createdAt int64, usageRaw []byte, firstMeta imageCallResult, err error) {
+	if gjson.GetBytes(payload, "type").String() != "response.completed" {
+		return nil, 0, nil, imageCallResult{}, fmt.Errorf("unexpected event type")
+	}
+
+	createdAt = gjson.GetBytes(payload, "response.created_at").Int()
+	if createdAt <= 0 {
+		createdAt = time.Now().Unix()
+	}
+
+	output := gjson.GetBytes(payload, "response.output")
+	if output.IsArray() {
+		for _, item := range output.Array() {
+			if item.Get("type").String() != "image_generation_call" {
+				continue
+			}
+			res := strings.TrimSpace(item.Get("result").String())
+			if res == "" {
+				continue
+			}
+			entry := imageCallResult{
+				Result:        res,
+				RevisedPrompt: strings.TrimSpace(item.Get("revised_prompt").String()),
+				OutputFormat:  strings.TrimSpace(item.Get("output_format").String()),
+				Size:          strings.TrimSpace(item.Get("size").String()),
+				Background:    strings.TrimSpace(item.Get("background").String()),
+				Quality:       strings.TrimSpace(item.Get("quality").String()),
+			}
+			if len(results) == 0 {
+				firstMeta = entry
+			}
+			results = append(results, entry)
+		}
+	}
+
+	if usage := gjson.GetBytes(payload, "response.tool_usage.image_gen"); usage.Exists() && usage.IsObject() {
+		usageRaw = []byte(usage.Raw)
+	}
+
+	return results, createdAt, usageRaw, firstMeta, nil
+}
+
+func buildImagesAPIResponse(results []imageCallResult, createdAt int64, usageRaw []byte, firstMeta imageCallResult, responseFormat string) ([]byte, error) {
+	out := []byte(`{"created":0,"data":[]}`)
+	out, _ = sjson.SetBytes(out, "created", createdAt)
+
+	responseFormat = strings.ToLower(strings.TrimSpace(responseFormat))
+	if responseFormat == "" {
+		responseFormat = "b64_json"
+	}
+
+	for _, img := range results {
+		item := []byte(`{}`)
+		if responseFormat == "url" {
+			mt := mimeTypeFromOutputFormat(img.OutputFormat)
+			item, _ = sjson.SetBytes(item, "url", "data:"+mt+";base64,"+img.Result)
+		} else {
+			item, _ = sjson.SetBytes(item, "b64_json", img.Result)
+		}
+		if img.RevisedPrompt != "" {
+			item, _ = sjson.SetBytes(item, "revised_prompt", img.RevisedPrompt)
+		}
+		out, _ = sjson.SetRawBytes(out, "data.-1", item)
+	}
+
+	if firstMeta.Background != "" {
+		out, _ = sjson.SetBytes(out, "background", firstMeta.Background)
+	}
+	if firstMeta.OutputFormat != "" {
+		out, _ = sjson.SetBytes(out, "output_format", firstMeta.OutputFormat)
+	}
+	if firstMeta.Quality != "" {
+		out, _ = sjson.SetBytes(out, "quality", firstMeta.Quality)
+	}
+	if firstMeta.Size != "" {
+		out, _ = sjson.SetBytes(out, "size", firstMeta.Size)
+	}
+
+	if len(usageRaw) > 0 && json.Valid(usageRaw) {
+		out, _ = sjson.SetRawBytes(out, "usage", usageRaw)
+	}
+
+	return out, nil
+}
+
+func (h *OpenAIAPIHandler) streamImagesFromResponses(c *gin.Context, responsesReq []byte, responseFormat string, streamPrefix string) {
+	flusher, ok := c.Writer.(http.Flusher)
+	if !ok {
+		c.JSON(http.StatusInternalServerError, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: "Streaming not supported",
+				Type:    "server_error",
+			},
+		})
+		return
+	}
+
+	cliCtx, cliCancel := h.GetContextWithCancel(h, c, context.Background())
+	dataChan, upstreamHeaders, errChan := h.ExecuteStreamWithAuthManager(cliCtx, "openai-response", defaultImagesMainModel, responsesReq, "")
+
+	setSSEHeaders := func() {
+		c.Header("Content-Type", "text/event-stream")
+		c.Header("Cache-Control", "no-cache")
+		c.Header("Connection", "keep-alive")
+		c.Header("Access-Control-Allow-Origin", "*")
+	}
+
+	writeEvent := func(eventName string, dataJSON []byte) {
+		if strings.TrimSpace(eventName) != "" {
+			_, _ = fmt.Fprintf(c.Writer, "event: %s\n", eventName)
+		}
+		_, _ = fmt.Fprintf(c.Writer, "data: %s\n\n", string(dataJSON))
+		flusher.Flush()
+	}
+
+	// Peek for first chunk/error so we can still return a JSON error body.
+	for {
+		select {
+		case <-c.Request.Context().Done():
+			cliCancel(c.Request.Context().Err())
+			return
+		case errMsg, ok := <-errChan:
+			if !ok {
+				errChan = nil
+				continue
+			}
+			h.WriteErrorResponse(c, errMsg)
+			if errMsg != nil {
+				cliCancel(errMsg.Error)
+			} else {
+				cliCancel(nil)
+			}
+			return
+		case chunk, ok := <-dataChan:
+			if !ok {
+				setSSEHeaders()
+				handlers.WriteUpstreamHeaders(c.Writer.Header(), upstreamHeaders)
+				_, _ = c.Writer.Write([]byte("\n"))
+				flusher.Flush()
+				cliCancel(nil)
+				return
+			}
+
+			setSSEHeaders()
+			handlers.WriteUpstreamHeaders(c.Writer.Header(), upstreamHeaders)
+
+			h.forwardImagesStream(cliCtx, c, flusher, func(err error) { cliCancel(err) }, dataChan, errChan, chunk, responseFormat, streamPrefix, writeEvent)
+			return
+		}
+	}
+}
+
+func (h *OpenAIAPIHandler) forwardImagesStream(ctx context.Context, c *gin.Context, flusher http.Flusher, cancel func(error), data <-chan []byte, errs <-chan *interfaces.ErrorMessage, firstChunk []byte, responseFormat string, streamPrefix string, writeEvent func(string, []byte)) {
+	acc := &sseFrameAccumulator{}
+
+	responseFormat = strings.ToLower(strings.TrimSpace(responseFormat))
+	if responseFormat == "" {
+		responseFormat = "b64_json"
+	}
+
+	emitError := func(errMsg *interfaces.ErrorMessage) {
+		if errMsg == nil {
+			return
+		}
+		status := http.StatusInternalServerError
+		if errMsg.StatusCode > 0 {
+			status = errMsg.StatusCode
+		}
+		errText := http.StatusText(status)
+		if errMsg.Error != nil && strings.TrimSpace(errMsg.Error.Error()) != "" {
+			errText = errMsg.Error.Error()
+		}
+		body := handlers.BuildErrorResponseBody(status, errText)
+		writeEvent("error", body)
+	}
+
+	processFrame := func(frame []byte) (done bool) {
+		for _, line := range bytes.Split(frame, []byte("\n")) {
+			trimmed := bytes.TrimSpace(bytes.TrimRight(line, "\r"))
+			if len(trimmed) == 0 || !bytes.HasPrefix(trimmed, []byte("data:")) {
+				continue
+			}
+			payload := bytes.TrimSpace(trimmed[len("data:"):])
+			if len(payload) == 0 || bytes.Equal(payload, []byte("[DONE]")) || !json.Valid(payload) {
+				continue
+			}
+
+			switch gjson.GetBytes(payload, "type").String() {
+			case "response.image_generation_call.partial_image":
+				b64 := strings.TrimSpace(gjson.GetBytes(payload, "partial_image_b64").String())
+				if b64 == "" {
+					continue
+				}
+				outputFormat := strings.TrimSpace(gjson.GetBytes(payload, "output_format").String())
+				index := gjson.GetBytes(payload, "partial_image_index").Int()
+				eventName := streamPrefix + ".partial_image"
+				data := []byte(`{"type":"","partial_image_index":0}`)
+				data, _ = sjson.SetBytes(data, "type", eventName)
+				data, _ = sjson.SetBytes(data, "partial_image_index", index)
+				if responseFormat == "url" {
+					mt := mimeTypeFromOutputFormat(outputFormat)
+					data, _ = sjson.SetBytes(data, "url", "data:"+mt+";base64,"+b64)
+				} else {
+					data, _ = sjson.SetBytes(data, "b64_json", b64)
+				}
+				writeEvent(eventName, data)
+			case "response.completed":
+				results, _, usageRaw, _, err := extractImagesFromResponsesCompleted(payload)
+				if err != nil {
+					emitError(&interfaces.ErrorMessage{StatusCode: http.StatusBadGateway, Error: err})
+					return true
+				}
+				if len(results) == 0 {
+					emitError(&interfaces.ErrorMessage{StatusCode: http.StatusBadGateway, Error: fmt.Errorf("upstream did not return image output")})
+					return true
+				}
+				eventName := streamPrefix + ".completed"
+				for _, img := range results {
+					data := []byte(`{"type":""}`)
+					data, _ = sjson.SetBytes(data, "type", eventName)
+					if responseFormat == "url" {
+						mt := mimeTypeFromOutputFormat(img.OutputFormat)
+						data, _ = sjson.SetBytes(data, "url", "data:"+mt+";base64,"+img.Result)
+					} else {
+						data, _ = sjson.SetBytes(data, "b64_json", img.Result)
+					}
+					if len(usageRaw) > 0 && json.Valid(usageRaw) {
+						data, _ = sjson.SetRawBytes(data, "usage", usageRaw)
+					}
+					writeEvent(eventName, data)
+				}
+				return true
+			}
+		}
+		return false
+	}
+
+	for _, frame := range acc.AddChunk(firstChunk) {
+		if processFrame(frame) {
+			cancel(nil)
+			return
+		}
+	}
+
+	for {
+		select {
+		case <-c.Request.Context().Done():
+			cancel(c.Request.Context().Err())
+			return
+		case errMsg, ok := <-errs:
+			if ok && errMsg != nil {
+				emitError(errMsg)
+				cancel(errMsg.Error)
+				return
+			}
+			errs = nil
+		case chunk, ok := <-data:
+			if !ok {
+				for _, frame := range acc.Flush() {
+					if processFrame(frame) {
+						cancel(nil)
+						return
+					}
+				}
+				cancel(nil)
+				return
+			}
+			for _, frame := range acc.AddChunk(chunk) {
+				if processFrame(frame) {
+					cancel(nil)
+					return
+				}
+			}
+		}
+	}
+}

sdk/cliproxy/service.go

@@ -1410,7 +1410,7 @@ func buildCodexConfigModels(entry *config.CodexKey) []*ModelInfo {
 	if entry == nil {
 		return nil
 	}
-	return buildConfigModels(entry.Models, "openai", "openai")
+	return registry.WithCodexBuiltins(buildConfigModels(entry.Models, "openai", "openai"))
 }
 
 func rewriteModelInfoName(name, oldID, newID string) string {