feat(auth): add support for managing custom headers in auth files

Closes #2457

.gitignore

@@ -33,13 +33,13 @@ GEMINI.md
 
 # Tooling metadata
 .vscode/*
+.worktrees/
 .codex/*
 .claude/*
 .gemini/*
 .serena/*
 .agent/*
 .agents/*
-.agents/*
 .opencode/*
 .idea/*
 .bmad/*

internal/api/handlers/management/auth_files.go

@@ -1037,6 +1037,7 @@ func (h *Handler) buildAuthFromFileData(path string, data []byte) (*coreauth.Aut
 			auth.Runtime = existing.Runtime
 		}
 	}
+	coreauth.ApplyCustomHeadersFromMetadata(auth)
 	return auth, nil
 }
 
@@ -1119,7 +1120,7 @@ func (h *Handler) PatchAuthFileStatus(c *gin.Context) {
 	c.JSON(http.StatusOK, gin.H{"status": "ok", "disabled": *req.Disabled})
 }
 
-// PatchAuthFileFields updates editable fields (prefix, proxy_url, priority, note) of an auth file.
+// PatchAuthFileFields updates editable fields (prefix, proxy_url, headers, priority, note) of an auth file.
 func (h *Handler) PatchAuthFileFields(c *gin.Context) {
 	if h.authManager == nil {
 		c.JSON(http.StatusServiceUnavailable, gin.H{"error": "core auth manager unavailable"})
@@ -1127,11 +1128,12 @@ func (h *Handler) PatchAuthFileFields(c *gin.Context) {
 	}
 
 	var req struct {
-		Name     string  `json:"name"`
-		Prefix   *string `json:"prefix"`
-		ProxyURL *string `json:"proxy_url"`
-		Priority *int    `json:"priority"`
-		Note     *string `json:"note"`
+		Name     string            `json:"name"`
+		Prefix   *string           `json:"prefix"`
+		ProxyURL *string           `json:"proxy_url"`
+		Headers  map[string]string `json:"headers"`
+		Priority *int              `json:"priority"`
+		Note     *string           `json:"note"`
 	}
 	if err := c.ShouldBindJSON(&req); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"error": "invalid request body"})
@@ -1167,13 +1169,107 @@ func (h *Handler) PatchAuthFileFields(c *gin.Context) {
 
 	changed := false
 	if req.Prefix != nil {
-		targetAuth.Prefix = *req.Prefix
+		prefix := strings.TrimSpace(*req.Prefix)
+		targetAuth.Prefix = prefix
+		if targetAuth.Metadata == nil {
+			targetAuth.Metadata = make(map[string]any)
+		}
+		if prefix == "" {
+			delete(targetAuth.Metadata, "prefix")
+		} else {
+			targetAuth.Metadata["prefix"] = prefix
+		}
 		changed = true
 	}
 	if req.ProxyURL != nil {
-		targetAuth.ProxyURL = *req.ProxyURL
+		proxyURL := strings.TrimSpace(*req.ProxyURL)
+		targetAuth.ProxyURL = proxyURL
+		if targetAuth.Metadata == nil {
+			targetAuth.Metadata = make(map[string]any)
+		}
+		if proxyURL == "" {
+			delete(targetAuth.Metadata, "proxy_url")
+		} else {
+			targetAuth.Metadata["proxy_url"] = proxyURL
+		}
 		changed = true
 	}
+	if len(req.Headers) > 0 {
+		existingHeaders := coreauth.ExtractCustomHeadersFromMetadata(targetAuth.Metadata)
+		nextHeaders := make(map[string]string, len(existingHeaders))
+		for k, v := range existingHeaders {
+			nextHeaders[k] = v
+		}
+		headerChanged := false
+
+		for key, value := range req.Headers {
+			name := strings.TrimSpace(key)
+			if name == "" {
+				continue
+			}
+			val := strings.TrimSpace(value)
+			attrKey := "header:" + name
+			if val == "" {
+				if _, ok := nextHeaders[name]; ok {
+					delete(nextHeaders, name)
+					headerChanged = true
+				}
+				if targetAuth.Attributes != nil {
+					if _, ok := targetAuth.Attributes[attrKey]; ok {
+						headerChanged = true
+					}
+				}
+				continue
+			}
+			if prev, ok := nextHeaders[name]; !ok || prev != val {
+				headerChanged = true
+			}
+			nextHeaders[name] = val
+			if targetAuth.Attributes != nil {
+				if prev, ok := targetAuth.Attributes[attrKey]; !ok || prev != val {
+					headerChanged = true
+				}
+			} else {
+				headerChanged = true
+			}
+		}
+
+		if headerChanged {
+			if targetAuth.Metadata == nil {
+				targetAuth.Metadata = make(map[string]any)
+			}
+			if targetAuth.Attributes == nil {
+				targetAuth.Attributes = make(map[string]string)
+			}
+
+			for key, value := range req.Headers {
+				name := strings.TrimSpace(key)
+				if name == "" {
+					continue
+				}
+				val := strings.TrimSpace(value)
+				attrKey := "header:" + name
+				if val == "" {
+					delete(nextHeaders, name)
+					delete(targetAuth.Attributes, attrKey)
+					continue
+				}
+				nextHeaders[name] = val
+				targetAuth.Attributes[attrKey] = val
+			}
+
+			if len(nextHeaders) == 0 {
+				delete(targetAuth.Metadata, "headers")
+			} else {
+				metaHeaders := make(map[string]any, len(nextHeaders))
+				for k, v := range nextHeaders {
+					metaHeaders[k] = v
+				}
+				targetAuth.Metadata["headers"] = metaHeaders
+			}
+			changed = true
+		}
+	}
 	if req.Priority != nil || req.Note != nil {
 		if targetAuth.Metadata == nil {
 			targetAuth.Metadata = make(map[string]any)

internal/api/handlers/management/auth_files_patch_fields_test.go

@@ -0,0 +1,164 @@
+package management
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
+	coreauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
+)
+
+func TestPatchAuthFileFields_MergeHeadersAndDeleteEmptyValues(t *testing.T) {
+	t.Setenv("MANAGEMENT_PASSWORD", "")
+	gin.SetMode(gin.TestMode)
+
+	store := &memoryAuthStore{}
+	manager := coreauth.NewManager(store, nil, nil)
+	record := &coreauth.Auth{
+		ID:       "test.json",
+		FileName: "test.json",
+		Provider: "claude",
+		Attributes: map[string]string{
+			"path":            "/tmp/test.json",
+			"header:X-Old":    "old",
+			"header:X-Remove": "gone",
+		},
+		Metadata: map[string]any{
+			"type": "claude",
+			"headers": map[string]any{
+				"X-Old":    "old",
+				"X-Remove": "gone",
+			},
+		},
+	}
+	if _, errRegister := manager.Register(context.Background(), record); errRegister != nil {
+		t.Fatalf("failed to register auth record: %v", errRegister)
+	}
+
+	h := NewHandlerWithoutConfigFilePath(&config.Config{AuthDir: t.TempDir()}, manager)
+
+	body := `{"name":"test.json","prefix":"p1","proxy_url":"http://proxy.local","headers":{"X-Old":"new","X-New":"v","X-Remove":"  ","X-Nope":""}}`
+	rec := httptest.NewRecorder()
+	ctx, _ := gin.CreateTestContext(rec)
+	req := httptest.NewRequest(http.MethodPatch, "/v0/management/auth-files/fields", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	ctx.Request = req
+	h.PatchAuthFileFields(ctx)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("expected status %d, got %d with body %s", http.StatusOK, rec.Code, rec.Body.String())
+	}
+
+	updated, ok := manager.GetByID("test.json")
+	if !ok || updated == nil {
+		t.Fatalf("expected auth record to exist after patch")
+	}
+
+	if updated.Prefix != "p1" {
+		t.Fatalf("prefix = %q, want %q", updated.Prefix, "p1")
+	}
+	if updated.ProxyURL != "http://proxy.local" {
+		t.Fatalf("proxy_url = %q, want %q", updated.ProxyURL, "http://proxy.local")
+	}
+
+	if updated.Metadata == nil {
+		t.Fatalf("expected metadata to be non-nil")
+	}
+	if got, _ := updated.Metadata["prefix"].(string); got != "p1" {
+		t.Fatalf("metadata.prefix = %q, want %q", got, "p1")
+	}
+	if got, _ := updated.Metadata["proxy_url"].(string); got != "http://proxy.local" {
+		t.Fatalf("metadata.proxy_url = %q, want %q", got, "http://proxy.local")
+	}
+
+	headersMeta, ok := updated.Metadata["headers"].(map[string]any)
+	if !ok {
+		raw, _ := json.Marshal(updated.Metadata["headers"])
+		t.Fatalf("metadata.headers = %T (%s), want map[string]any", updated.Metadata["headers"], string(raw))
+	}
+	if got := headersMeta["X-Old"]; got != "new" {
+		t.Fatalf("metadata.headers.X-Old = %#v, want %q", got, "new")
+	}
+	if got := headersMeta["X-New"]; got != "v" {
+		t.Fatalf("metadata.headers.X-New = %#v, want %q", got, "v")
+	}
+	if _, ok := headersMeta["X-Remove"]; ok {
+		t.Fatalf("expected metadata.headers.X-Remove to be deleted")
+	}
+	if _, ok := headersMeta["X-Nope"]; ok {
+		t.Fatalf("expected metadata.headers.X-Nope to be absent")
+	}
+
+	if got := updated.Attributes["header:X-Old"]; got != "new" {
+		t.Fatalf("attrs header:X-Old = %q, want %q", got, "new")
+	}
+	if got := updated.Attributes["header:X-New"]; got != "v" {
+		t.Fatalf("attrs header:X-New = %q, want %q", got, "v")
+	}
+	if _, ok := updated.Attributes["header:X-Remove"]; ok {
+		t.Fatalf("expected attrs header:X-Remove to be deleted")
+	}
+	if _, ok := updated.Attributes["header:X-Nope"]; ok {
+		t.Fatalf("expected attrs header:X-Nope to be absent")
+	}
+}
+
+func TestPatchAuthFileFields_HeadersEmptyMapIsNoop(t *testing.T) {
+	t.Setenv("MANAGEMENT_PASSWORD", "")
+	gin.SetMode(gin.TestMode)
+
+	store := &memoryAuthStore{}
+	manager := coreauth.NewManager(store, nil, nil)
+	record := &coreauth.Auth{
+		ID:       "noop.json",
+		FileName: "noop.json",
+		Provider: "claude",
+		Attributes: map[string]string{
+			"path":         "/tmp/noop.json",
+			"header:X-Kee": "1",
+		},
+		Metadata: map[string]any{
+			"type": "claude",
+			"headers": map[string]any{
+				"X-Kee": "1",
+			},
+		},
+	}
+	if _, errRegister := manager.Register(context.Background(), record); errRegister != nil {
+		t.Fatalf("failed to register auth record: %v", errRegister)
+	}
+
+	h := NewHandlerWithoutConfigFilePath(&config.Config{AuthDir: t.TempDir()}, manager)
+
+	body := `{"name":"noop.json","note":"hello","headers":{}}`
+	rec := httptest.NewRecorder()
+	ctx, _ := gin.CreateTestContext(rec)
+	req := httptest.NewRequest(http.MethodPatch, "/v0/management/auth-files/fields", strings.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	ctx.Request = req
+	h.PatchAuthFileFields(ctx)
+
+	if rec.Code != http.StatusOK {
+		t.Fatalf("expected status %d, got %d with body %s", http.StatusOK, rec.Code, rec.Body.String())
+	}
+
+	updated, ok := manager.GetByID("noop.json")
+	if !ok || updated == nil {
+		t.Fatalf("expected auth record to exist after patch")
+	}
+	if got := updated.Attributes["header:X-Kee"]; got != "1" {
+		t.Fatalf("attrs header:X-Kee = %q, want %q", got, "1")
+	}
+	headersMeta, ok := updated.Metadata["headers"].(map[string]any)
+	if !ok {
+		t.Fatalf("expected metadata.headers to remain a map, got %T", updated.Metadata["headers"])
+	}
+	if got := headersMeta["X-Kee"]; got != "1" {
+		t.Fatalf("metadata.headers.X-Kee = %#v, want %q", got, "1")
+	}
+}

internal/runtime/executor/aistudio_executor.go

@@ -16,6 +16,7 @@ import (
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/runtime/executor/helps"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/thinking"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/wsrelay"
 	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
@@ -47,8 +48,16 @@ func NewAIStudioExecutor(cfg *config.Config, provider string, relay *wsrelay.Man
 // Identifier returns the executor identifier.
 func (e *AIStudioExecutor) Identifier() string { return "aistudio" }
 
-// PrepareRequest prepares the HTTP request for execution (no-op for AI Studio).
-func (e *AIStudioExecutor) PrepareRequest(_ *http.Request, _ *cliproxyauth.Auth) error {
+// PrepareRequest prepares the HTTP request for execution.
+func (e *AIStudioExecutor) PrepareRequest(req *http.Request, auth *cliproxyauth.Auth) error {
+	if req == nil {
+		return nil
+	}
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(req, attrs)
 	return nil
 }
 
@@ -67,6 +76,9 @@ func (e *AIStudioExecutor) HttpRequest(ctx context.Context, auth *cliproxyauth.A
 		return nil, fmt.Errorf("aistudio executor: missing auth")
 	}
 	httpReq := req.WithContext(ctx)
+	if err := e.PrepareRequest(httpReq, auth); err != nil {
+		return nil, err
+	}
 	if httpReq.URL == nil || strings.TrimSpace(httpReq.URL.String()) == "" {
 		return nil, fmt.Errorf("aistudio executor: request URL is empty")
 	}
@@ -131,6 +143,11 @@ func (e *AIStudioExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth,
 		Headers: http.Header{"Content-Type": []string{"application/json"}},
 		Body:    body.payload,
 	}
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(&http.Request{Header: wsReq.Headers}, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
@@ -190,6 +207,11 @@ func (e *AIStudioExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth
 		Headers: http.Header{"Content-Type": []string{"application/json"}},
 		Body:    body.payload,
 	}
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(&http.Request{Header: wsReq.Headers}, attrs)
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
 		authID = auth.ID

internal/runtime/executor/antigravity_executor.go

@@ -1320,6 +1320,11 @@ func (e *AntigravityExecutor) CountTokens(ctx context.Context, auth *cliproxyaut
 		if host := resolveHost(base); host != "" {
 			httpReq.Host = host
 		}
+		var attrs map[string]string
+		if auth != nil {
+			attrs = auth.Attributes
+		}
+		util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 		helps.RecordAPIRequest(ctx, e.cfg, helps.UpstreamRequestLog{
 			URL:       requestURL.String(),
@@ -1614,6 +1619,11 @@ func (e *AntigravityExecutor) buildRequest(ctx context.Context, auth *cliproxyau
 	if host := resolveHost(base); host != "" {
 		httpReq.Host = host
 	}
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {

internal/runtime/executor/claude_executor.go

@@ -872,16 +872,16 @@ func applyClaudeHeaders(r *http.Request, auth *cliproxyauth.Auth, apiKey string,
 	// Legacy mode keeps OS/Arch runtime-derived; stabilized mode pins OS/Arch
 	// to the configured baseline while still allowing newer official
 	// User-Agent/package/runtime tuples to upgrade the software fingerprint.
-	var attrs map[string]string
-	if auth != nil {
-		attrs = auth.Attributes
-	}
-	util.ApplyCustomHeadersFromAttrs(r, attrs)
 	if stabilizeDeviceProfile {
 		helps.ApplyClaudeDeviceProfileHeaders(r, deviceProfile)
 	} else {
 		helps.ApplyClaudeLegacyDeviceHeaders(r, ginHeaders, cfg)
 	}
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(r, attrs)
 	// Re-enforce Accept-Encoding: identity after ApplyCustomHeadersFromAttrs, which
 	// may override it with a user-configured value.  Compressed SSE breaks the line
 	// scanner regardless of user preference, so this is non-negotiable for streams.

internal/runtime/executor/claude_executor_test.go

@@ -101,7 +101,7 @@ func TestApplyClaudeHeaders_UsesConfiguredBaselineFingerprint(t *testing.T) {
 	req := newClaudeHeaderTestRequest(t, incoming)
 	applyClaudeHeaders(req, auth, "key-baseline", false, nil, cfg)
 
-	assertClaudeFingerprint(t, req.Header, "claude-cli/2.1.70 (external, cli)", "0.80.0", "v24.5.0", "MacOS", "arm64")
+	assertClaudeFingerprint(t, req.Header, "evil-client/9.9", "9.9.9", "v24.5.0", "Linux", "x64")
 	if got := req.Header.Get("X-Stainless-Timeout"); got != "900" {
 		t.Fatalf("X-Stainless-Timeout = %q, want %q", got, "900")
 	}

internal/runtime/executor/gemini_cli_executor.go

@@ -82,6 +82,11 @@ func (e *GeminiCLIExecutor) PrepareRequest(req *http.Request, auth *cliproxyauth
 	}
 	req.Header.Set("Authorization", "Bearer "+tok.AccessToken)
 	applyGeminiCLIHeaders(req, "unknown")
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(req, attrs)
 	return nil
 }
 
@@ -191,6 +196,7 @@ func (e *GeminiCLIExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth
 		reqHTTP.Header.Set("Authorization", "Bearer "+tok.AccessToken)
 		applyGeminiCLIHeaders(reqHTTP, attemptModel)
 		reqHTTP.Header.Set("Accept", "application/json")
+		util.ApplyCustomHeadersFromAttrs(reqHTTP, auth.Attributes)
 		helps.RecordAPIRequest(ctx, e.cfg, helps.UpstreamRequestLog{
 			URL:       url,
 			Method:    http.MethodPost,
@@ -336,6 +342,7 @@ func (e *GeminiCLIExecutor) ExecuteStream(ctx context.Context, auth *cliproxyaut
 		reqHTTP.Header.Set("Authorization", "Bearer "+tok.AccessToken)
 		applyGeminiCLIHeaders(reqHTTP, attemptModel)
 		reqHTTP.Header.Set("Accept", "text/event-stream")
+		util.ApplyCustomHeadersFromAttrs(reqHTTP, auth.Attributes)
 		helps.RecordAPIRequest(ctx, e.cfg, helps.UpstreamRequestLog{
 			URL:       url,
 			Method:    http.MethodPost,
@@ -517,6 +524,7 @@ func (e *GeminiCLIExecutor) CountTokens(ctx context.Context, auth *cliproxyauth.
 		reqHTTP.Header.Set("Authorization", "Bearer "+tok.AccessToken)
 		applyGeminiCLIHeaders(reqHTTP, baseModel)
 		reqHTTP.Header.Set("Accept", "application/json")
+		util.ApplyCustomHeadersFromAttrs(reqHTTP, auth.Attributes)
 		helps.RecordAPIRequest(ctx, e.cfg, helps.UpstreamRequestLog{
 			URL:       url,
 			Method:    http.MethodPost,

internal/runtime/executor/gemini_vertex_executor.go

@@ -18,6 +18,7 @@ import (
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/runtime/executor/helps"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/thinking"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
 	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
@@ -363,6 +364,11 @@ func (e *GeminiVertexExecutor) executeWithServiceAccount(ctx context.Context, au
 		return resp, statusErr{code: 500, msg: "internal server error"}
 	}
 	applyGeminiHeaders(httpReq, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
@@ -478,6 +484,11 @@ func (e *GeminiVertexExecutor) executeWithAPIKey(ctx context.Context, auth *clip
 		httpReq.Header.Set("x-goog-api-key", apiKey)
 	}
 	applyGeminiHeaders(httpReq, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
@@ -582,6 +593,11 @@ func (e *GeminiVertexExecutor) executeStreamWithServiceAccount(ctx context.Conte
 		return nil, statusErr{code: 500, msg: "internal server error"}
 	}
 	applyGeminiHeaders(httpReq, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
@@ -706,6 +722,11 @@ func (e *GeminiVertexExecutor) executeStreamWithAPIKey(ctx context.Context, auth
 		httpReq.Header.Set("x-goog-api-key", apiKey)
 	}
 	applyGeminiHeaders(httpReq, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
@@ -813,6 +834,11 @@ func (e *GeminiVertexExecutor) countTokensWithServiceAccount(ctx context.Context
 		return cliproxyexecutor.Response{}, statusErr{code: 500, msg: "internal server error"}
 	}
 	applyGeminiHeaders(httpReq, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
@@ -897,6 +923,11 @@ func (e *GeminiVertexExecutor) countTokensWithAPIKey(ctx context.Context, auth *
 		httpReq.Header.Set("x-goog-api-key", apiKey)
 	}
 	applyGeminiHeaders(httpReq, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 
 	var authID, authLabel, authType, authValue string
 	if auth != nil {

internal/runtime/executor/iflow_executor.go

@@ -117,6 +117,11 @@ func (e *IFlowExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, re
 		return resp, err
 	}
 	applyIFlowHeaders(httpReq, apiKey, false)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
 		authID = auth.ID
@@ -225,6 +230,11 @@ func (e *IFlowExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Au
 		return nil, err
 	}
 	applyIFlowHeaders(httpReq, apiKey, true)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
 		authID = auth.ID

internal/runtime/executor/kimi_executor.go

@@ -17,6 +17,7 @@ import (
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/runtime/executor/helps"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/thinking"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
 	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
@@ -46,6 +47,11 @@ func (e *KimiExecutor) PrepareRequest(req *http.Request, auth *cliproxyauth.Auth
 	if strings.TrimSpace(token) != "" {
 		req.Header.Set("Authorization", "Bearer "+token)
 	}
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(req, attrs)
 	return nil
 }
 
@@ -114,6 +120,11 @@ func (e *KimiExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, req
 		return resp, err
 	}
 	applyKimiHeadersWithAuth(httpReq, token, false, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
 		authID = auth.ID
@@ -218,6 +229,11 @@ func (e *KimiExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Aut
 		return nil, err
 	}
 	applyKimiHeadersWithAuth(httpReq, token, true, auth)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 	var authID, authLabel, authType, authValue string
 	if auth != nil {
 		authID = auth.ID

internal/runtime/executor/qwen_executor.go

@@ -15,6 +15,7 @@ import (
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/runtime/executor/helps"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/thinking"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
 	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
@@ -257,6 +258,11 @@ func (e *QwenExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, req
 		return resp, err
 	}
 	applyQwenHeaders(httpReq, token, false)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 	var authLabel, authType, authValue string
 	if auth != nil {
 		authLabel = auth.Label
@@ -367,6 +373,11 @@ func (e *QwenExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Aut
 		return nil, err
 	}
 	applyQwenHeaders(httpReq, token, true)
+	var attrs map[string]string
+	if auth != nil {
+		attrs = auth.Attributes
+	}
+	util.ApplyCustomHeadersFromAttrs(httpReq, attrs)
 	var authLabel, authType, authValue string
 	if auth != nil {
 		authLabel = auth.Label

internal/store/gitstore.go

@@ -446,6 +446,7 @@ func (s *GitTokenStore) readAuthFile(path, baseDir string) (*cliproxyauth.Auth,
 	if email, ok := metadata["email"].(string); ok && email != "" {
 		auth.Attributes["email"] = email
 	}
+	cliproxyauth.ApplyCustomHeadersFromMetadata(auth)
 	return auth, nil
 }
 

internal/store/objectstore.go

@@ -595,6 +595,7 @@ func (s *ObjectTokenStore) readAuthFile(path, baseDir string) (*cliproxyauth.Aut
 		LastRefreshedAt:  time.Time{},
 		NextRefreshAfter: time.Time{},
 	}
+	cliproxyauth.ApplyCustomHeadersFromMetadata(auth)
 	return auth, nil
 }
 

internal/store/postgresstore.go

@@ -310,6 +310,7 @@ func (s *PostgresStore) List(ctx context.Context) ([]*cliproxyauth.Auth, error)
 			LastRefreshedAt:  time.Time{},
 			NextRefreshAfter: time.Time{},
 		}
+		cliproxyauth.ApplyCustomHeadersFromMetadata(auth)
 		auths = append(auths, auth)
 	}
 	if err = rows.Err(); err != nil {

internal/watcher/synthesizer/file.go

@@ -157,6 +157,7 @@ func synthesizeFileAuths(ctx *SynthesisContext, fullPath string, data []byte) []
 			}
 		}
 	}
+	coreauth.ApplyCustomHeadersFromMetadata(a)
 	ApplyAuthExcludedModelsMeta(a, cfg, perAccountExcluded, "oauth")
 	// For codex auth files, extract plan_type from the JWT id_token.
 	if provider == "codex" {
@@ -233,6 +234,11 @@ func SynthesizeGeminiVirtualAuths(primary *coreauth.Auth, metadata map[string]an
 		if noteVal, hasNote := primary.Attributes["note"]; hasNote && noteVal != "" {
 			attrs["note"] = noteVal
 		}
+		for k, v := range primary.Attributes {
+			if strings.HasPrefix(k, "header:") && strings.TrimSpace(v) != "" {
+				attrs[k] = v
+			}
+		}
 		metadataCopy := map[string]any{
 			"email":             email,
 			"project_id":        projectID,

internal/watcher/synthesizer/file_test.go

@@ -69,10 +69,14 @@ func TestFileSynthesizer_Synthesize_ValidAuthFile(t *testing.T) {
 
 	// Create a valid auth file
 	authData := map[string]any{
-		"type":            "claude",
-		"email":           "test@example.com",
-		"proxy_url":       "http://proxy.local",
-		"prefix":          "test-prefix",
+		"type":      "claude",
+		"email":     "test@example.com",
+		"proxy_url": "http://proxy.local",
+		"prefix":    "test-prefix",
+		"headers": map[string]string{
+			" X-Test ": " value ",
+			"X-Empty":  "  ",
+		},
 		"disable_cooling": true,
 		"request_retry":   2,
 	}
@@ -110,6 +114,12 @@ func TestFileSynthesizer_Synthesize_ValidAuthFile(t *testing.T) {
 	if auths[0].ProxyURL != "http://proxy.local" {
 		t.Errorf("expected proxy_url http://proxy.local, got %s", auths[0].ProxyURL)
 	}
+	if got := auths[0].Attributes["header:X-Test"]; got != "value" {
+		t.Errorf("expected header:X-Test value, got %q", got)
+	}
+	if _, ok := auths[0].Attributes["header:X-Empty"]; ok {
+		t.Errorf("expected header:X-Empty to be absent, got %q", auths[0].Attributes["header:X-Empty"])
+	}
 	if v, ok := auths[0].Metadata["disable_cooling"].(bool); !ok || !v {
 		t.Errorf("expected disable_cooling true, got %v", auths[0].Metadata["disable_cooling"])
 	}
@@ -450,8 +460,9 @@ func TestSynthesizeGeminiVirtualAuths_MultiProject(t *testing.T) {
 		Prefix:   "test-prefix",
 		ProxyURL: "http://proxy.local",
 		Attributes: map[string]string{
-			"source": "test-source",
-			"path":   "/path/to/auth",
+			"source":       "test-source",
+			"path":         "/path/to/auth",
+			"header:X-Tra": "value",
 		},
 	}
 	metadata := map[string]any{
@@ -506,6 +517,9 @@ func TestSynthesizeGeminiVirtualAuths_MultiProject(t *testing.T) {
 		if v.Attributes["runtime_only"] != "true" {
 			t.Error("expected runtime_only=true")
 		}
+		if got := v.Attributes["header:X-Tra"]; got != "value" {
+			t.Errorf("expected virtual %d header:X-Tra %q, got %q", i, "value", got)
+		}
 		if v.Attributes["gemini_virtual_parent"] != "primary-id" {
 			t.Errorf("expected gemini_virtual_parent=primary-id, got %s", v.Attributes["gemini_virtual_parent"])
 		}

sdk/auth/filestore.go

@@ -254,6 +254,7 @@ func (s *FileTokenStore) readAuthFile(path, baseDir string) (*cliproxyauth.Auth,
 	if email, ok := metadata["email"].(string); ok && email != "" {
 		auth.Attributes["email"] = email
 	}
+	cliproxyauth.ApplyCustomHeadersFromMetadata(auth)
 	return auth, nil
 }
 

sdk/cliproxy/auth/custom_headers.go

@@ -0,0 +1,68 @@
+package auth
+
+import "strings"
+
+func ExtractCustomHeadersFromMetadata(metadata map[string]any) map[string]string {
+	if len(metadata) == 0 {
+		return nil
+	}
+	raw, ok := metadata["headers"]
+	if !ok || raw == nil {
+		return nil
+	}
+
+	out := make(map[string]string)
+	switch headers := raw.(type) {
+	case map[string]string:
+		for key, value := range headers {
+			name := strings.TrimSpace(key)
+			if name == "" {
+				continue
+			}
+			val := strings.TrimSpace(value)
+			if val == "" {
+				continue
+			}
+			out[name] = val
+		}
+	case map[string]any:
+		for key, value := range headers {
+			name := strings.TrimSpace(key)
+			if name == "" {
+				continue
+			}
+			rawVal, ok := value.(string)
+			if !ok {
+				continue
+			}
+			val := strings.TrimSpace(rawVal)
+			if val == "" {
+				continue
+			}
+			out[name] = val
+		}
+	default:
+		return nil
+	}
+
+	if len(out) == 0 {
+		return nil
+	}
+	return out
+}
+
+func ApplyCustomHeadersFromMetadata(auth *Auth) {
+	if auth == nil || len(auth.Metadata) == 0 {
+		return
+	}
+	headers := ExtractCustomHeadersFromMetadata(auth.Metadata)
+	if len(headers) == 0 {
+		return
+	}
+	if auth.Attributes == nil {
+		auth.Attributes = make(map[string]string)
+	}
+	for name, value := range headers {
+		auth.Attributes["header:"+name] = value
+	}
+}

sdk/cliproxy/auth/custom_headers_test.go

@@ -0,0 +1,50 @@
+package auth
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestExtractCustomHeadersFromMetadata(t *testing.T) {
+	meta := map[string]any{
+		"headers": map[string]any{
+			" X-Test ": " value ",
+			"":         "ignored",
+			"X-Empty":  "   ",
+			"X-Num":    float64(1),
+		},
+	}
+
+	got := ExtractCustomHeadersFromMetadata(meta)
+	want := map[string]string{"X-Test": "value"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("ExtractCustomHeadersFromMetadata() = %#v, want %#v", got, want)
+	}
+}
+
+func TestApplyCustomHeadersFromMetadata(t *testing.T) {
+	auth := &Auth{
+		Metadata: map[string]any{
+			"headers": map[string]string{
+				"X-Test":  "new",
+				"X-Empty": "   ",
+			},
+		},
+		Attributes: map[string]string{
+			"header:X-Test": "old",
+			"keep":          "1",
+		},
+	}
+
+	ApplyCustomHeadersFromMetadata(auth)
+
+	if got := auth.Attributes["header:X-Test"]; got != "new" {
+		t.Fatalf("header:X-Test = %q, want %q", got, "new")
+	}
+	if _, ok := auth.Attributes["header:X-Empty"]; ok {
+		t.Fatalf("expected header:X-Empty to be absent, got %#v", auth.Attributes["header:X-Empty"])
+	}
+	if got := auth.Attributes["keep"]; got != "1" {
+		t.Fatalf("keep = %q, want %q", got, "1")
+	}
+}