feat(translators): add token counting support for Claude and Gemini responses

- Implemented `TokenCount` transform method across translators to calculate token usage.
- Integrated token counting logic into executor pipelines for Claude, Gemini, and CLI translators.
- Added corresponding API endpoints and handlers (`/messages/count_tokens`) for token usage retrieval.
- Enhanced translation registry to support `TokenCount` functionality alongside existing response types.

internal/api/handlers/claude/code_handlers.go

@@ -82,6 +82,43 @@ func (h *ClaudeCodeAPIHandler) ClaudeMessages(c *gin.Context) {
 	}
 }
 
+// ClaudeMessages handles Claude-compatible streaming chat completions.
+// This function implements a sophisticated client rotation and quota management system
+// to ensure high availability and optimal resource utilization across multiple backend clients.
+//
+// Parameters:
+//   - c: The Gin context for the request.
+func (h *ClaudeCodeAPIHandler) ClaudeCountTokens(c *gin.Context) {
+	// Extract raw JSON data from the incoming request
+	rawJSON, err := c.GetRawData()
+	// If data retrieval fails, return a 400 Bad Request error.
+	if err != nil {
+		c.JSON(http.StatusBadRequest, handlers.ErrorResponse{
+			Error: handlers.ErrorDetail{
+				Message: fmt.Sprintf("Invalid request: %v", err),
+				Type:    "invalid_request_error",
+			},
+		})
+		return
+	}
+
+	c.Header("Content-Type", "application/json")
+
+	alt := h.GetAlt(c)
+	cliCtx, cliCancel := h.GetContextWithCancel(h, c, context.Background())
+
+	modelName := gjson.GetBytes(rawJSON, "model").String()
+
+	resp, errMsg := h.ExecuteCountWithAuthManager(cliCtx, h.HandlerType(), modelName, rawJSON, alt)
+	if errMsg != nil {
+		h.WriteErrorResponse(c, errMsg)
+		cliCancel(errMsg.Error)
+		return
+	}
+	_, _ = c.Writer.Write(resp)
+	cliCancel()
+}
+
 // ClaudeModels handles the Claude models listing endpoint.
 // It returns a JSON response containing available Claude models and their specifications.
 //

internal/api/server.go

@@ -198,6 +198,7 @@ func (s *Server) setupRoutes() {
 		v1.POST("/chat/completions", openaiHandlers.ChatCompletions)
 		v1.POST("/completions", openaiHandlers.Completions)
 		v1.POST("/messages", claudeCodeHandlers.ClaudeMessages)
+		v1.POST("/messages/count_tokens", claudeCodeHandlers.ClaudeCountTokens)
 		v1.POST("/responses", openaiResponsesHandlers.Responses)
 	}
 

internal/runtime/executor/claude_executor.go

@@ -18,6 +18,7 @@ import (
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
 	log "github.com/sirupsen/logrus"
+	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
 
 	"github.com/gin-gonic/gin"
@@ -175,7 +176,68 @@ func (e *ClaudeExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.A
 }
 
 func (e *ClaudeExecutor) CountTokens(ctx context.Context, auth *cliproxyauth.Auth, req cliproxyexecutor.Request, opts cliproxyexecutor.Options) (cliproxyexecutor.Response, error) {
-	return cliproxyexecutor.Response{Payload: []byte{}}, fmt.Errorf("not implemented")
+	apiKey, baseURL := claudeCreds(auth)
+	if apiKey == "" {
+		return NewClientAdapter("claude").Execute(ctx, auth, req, opts)
+	}
+	if baseURL == "" {
+		baseURL = "https://api.anthropic.com"
+	}
+
+	from := opts.SourceFormat
+	to := sdktranslator.FromString("claude")
+	// Use streaming translation to preserve function calling, except for claude.
+	stream := from != to
+	body := sdktranslator.TranslateRequest(from, to, req.Model, bytes.Clone(req.Payload), stream)
+
+	if !strings.HasPrefix(req.Model, "claude-3-5-haiku") {
+		body, _ = sjson.SetRawBytes(body, "system", []byte(misc.ClaudeCodeInstructions))
+	}
+
+	url := fmt.Sprintf("%s/v1/messages/count_tokens?beta=true", baseURL)
+	recordAPIRequest(ctx, e.cfg, body)
+	httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
+	if err != nil {
+		return cliproxyexecutor.Response{}, err
+	}
+	applyClaudeHeaders(httpReq, apiKey, false)
+
+	httpClient := &http.Client{}
+	if rt, ok := ctx.Value("cliproxy.roundtripper").(http.RoundTripper); ok && rt != nil {
+		httpClient.Transport = rt
+	}
+	resp, err := httpClient.Do(httpReq)
+	if err != nil {
+		return cliproxyexecutor.Response{}, err
+	}
+	defer func() {
+		if errClose := resp.Body.Close(); errClose != nil {
+			log.Errorf("response body close error: %v", errClose)
+		}
+	}()
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		b, _ := io.ReadAll(resp.Body)
+		appendAPIResponseChunk(ctx, e.cfg, b)
+		return cliproxyexecutor.Response{}, statusErr{code: resp.StatusCode, msg: string(b)}
+	}
+	reader := io.Reader(resp.Body)
+	var decoder *zstd.Decoder
+	if hasZSTDEcoding(resp.Header.Get("Content-Encoding")) {
+		decoder, err = zstd.NewReader(resp.Body)
+		if err != nil {
+			return cliproxyexecutor.Response{}, fmt.Errorf("failed to initialize zstd decoder: %w", err)
+		}
+		reader = decoder
+		defer decoder.Close()
+	}
+	data, err := io.ReadAll(reader)
+	if err != nil {
+		return cliproxyexecutor.Response{}, err
+	}
+	appendAPIResponseChunk(ctx, e.cfg, data)
+	count := gjson.GetBytes(data, "input_tokens").Int()
+	out := sdktranslator.TranslateTokenCount(ctx, to, from, count, data)
+	return cliproxyexecutor.Response{Payload: []byte(out)}, nil
 }
 
 func (e *ClaudeExecutor) Refresh(ctx context.Context, auth *cliproxyauth.Auth) (*cliproxyauth.Auth, error) {

internal/runtime/executor/codex_executor.go

@@ -53,9 +53,11 @@ func (e *CodexExecutor) Execute(ctx context.Context, auth *cliproxyauth.Auth, re
 	to := sdktranslator.FromString("codex")
 	body := sdktranslator.TranslateRequest(from, to, req.Model, bytes.Clone(req.Payload), false)
 
-	if util.InArray([]string{"gpt-5-minimal", "gpt-5-low", "gpt-5-medium", "gpt-5-high"}, req.Model) {
+	if util.InArray([]string{"gpt-5", "gpt-5-minimal", "gpt-5-low", "gpt-5-medium", "gpt-5-high"}, req.Model) {
 		body, _ = sjson.SetBytes(body, "model", "gpt-5")
 		switch req.Model {
+		case "gpt-5":
+			body, _ = sjson.DeleteBytes(body, "reasoning.effort")
 		case "gpt-5-minimal":
 			body, _ = sjson.SetBytes(body, "reasoning.effort", "minimal")
 		case "gpt-5-low":
@@ -146,9 +148,11 @@ func (e *CodexExecutor) ExecuteStream(ctx context.Context, auth *cliproxyauth.Au
 	to := sdktranslator.FromString("codex")
 	body := sdktranslator.TranslateRequest(from, to, req.Model, bytes.Clone(req.Payload), true)
 
-	if util.InArray([]string{"gpt-5-minimal", "gpt-5-low", "gpt-5-medium", "gpt-5-high"}, req.Model) {
+	if util.InArray([]string{"gpt-5", "gpt-5-minimal", "gpt-5-low", "gpt-5-medium", "gpt-5-high"}, req.Model) {
 		body, _ = sjson.SetBytes(body, "model", "gpt-5")
 		switch req.Model {
+		case "gpt-5":
+			body, _ = sjson.DeleteBytes(body, "reasoning.effort")
 		case "gpt-5-minimal":
 			body, _ = sjson.SetBytes(body, "reasoning.effort", "minimal")
 		case "gpt-5-low":

internal/runtime/executor/gemini_cli_executor.go

@@ -18,6 +18,7 @@ import (
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
 	log "github.com/sirupsen/logrus"
+	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
 	"golang.org/x/oauth2"
 	"golang.org/x/oauth2/google"
@@ -156,7 +157,6 @@ func (e *GeminiCLIExecutor) ExecuteStream(ctx context.Context, auth *cliproxyaut
 
 	httpClient := newHTTPClient(ctx, 0)
 	respCtx := context.WithValue(ctx, "alt", opts.Alt)
-	dataTag := []byte("data:")
 
 	var lastStatus int
 	var lastBody []byte
@@ -321,8 +321,8 @@ func (e *GeminiCLIExecutor) CountTokens(ctx context.Context, auth *cliproxyauth.
 		_ = resp.Body.Close()
 		appendAPIResponseChunk(ctx, e.cfg, data)
 		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
-			var param any
-			translated := sdktranslator.TranslateNonStream(respCtx, to, from, attemptModel, bytes.Clone(opts.OriginalRequest), payload, data, &param)
+			count := gjson.GetBytes(data, "totalTokens").Int()
+			translated := sdktranslator.TranslateTokenCount(respCtx, to, from, count, data)
 			return cliproxyexecutor.Response{Payload: []byte(translated)}, nil
 		}
 		lastStatus = resp.StatusCode

internal/runtime/executor/gemini_executor.go

@@ -15,6 +15,7 @@ import (
 	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/executor"
 	sdktranslator "github.com/router-for-me/CLIProxyAPI/v6/sdk/translator"
 	log "github.com/sirupsen/logrus"
+	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
 	"golang.org/x/oauth2"
 	"golang.org/x/oauth2/google"
@@ -182,9 +183,11 @@ func (e *GeminiExecutor) CountTokens(ctx context.Context, auth *cliproxyauth.Aut
 	translatedReq := sdktranslator.TranslateRequest(from, to, req.Model, bytes.Clone(req.Payload), false)
 	respCtx := context.WithValue(ctx, "alt", opts.Alt)
 	translatedReq, _ = sjson.DeleteBytes(translatedReq, "tools")
+	translatedReq, _ = sjson.DeleteBytes(translatedReq, "generationConfig")
 
 	url := fmt.Sprintf("%s/%s/models/%s:%s", glEndpoint, glAPIVersion, req.Model, "countTokens")
 	recordAPIRequest(ctx, e.cfg, translatedReq)
+
 	requestBody := bytes.NewReader(translatedReq)
 
 	httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, url, requestBody)
@@ -218,8 +221,8 @@ func (e *GeminiExecutor) CountTokens(ctx context.Context, auth *cliproxyauth.Aut
 		return cliproxyexecutor.Response{}, statusErr{code: resp.StatusCode, msg: string(data)}
 	}
 
-	var param any
-	translated := sdktranslator.TranslateNonStream(respCtx, to, from, req.Model, bytes.Clone(opts.OriginalRequest), translatedReq, data, &param)
+	count := gjson.GetBytes(data, "totalTokens").Int()
+	translated := sdktranslator.TranslateTokenCount(respCtx, to, from, count, data)
 	return cliproxyexecutor.Response{Payload: []byte(translated)}, nil
 }
 

internal/translator/claude/gemini-cli/claude_gemini-cli_response.go

@@ -54,5 +54,8 @@ func ConvertClaudeResponseToGeminiCLINonStream(ctx context.Context, modelName st
 	json := `{"response": {}}`
 	strJSON, _ = sjson.SetRaw(json, "response", strJSON)
 	return strJSON
-
+}
+
+func GeminiCLITokenCount(ctx context.Context, count int64) string {
+	return GeminiTokenCount(ctx, count)
 }

internal/translator/claude/gemini-cli/init.go

@@ -12,8 +12,9 @@ func init() {
 		Claude,
 		ConvertGeminiCLIRequestToClaude,
 		interfaces.TranslateResponse{
-			Stream:    ConvertClaudeResponseToGeminiCLI,
-			NonStream: ConvertClaudeResponseToGeminiCLINonStream,
+			Stream:     ConvertClaudeResponseToGeminiCLI,
+			NonStream:  ConvertClaudeResponseToGeminiCLINonStream,
+			TokenCount: GeminiCLITokenCount,
 		},
 	)
 }

internal/translator/claude/gemini/claude_gemini_response.go

@@ -9,6 +9,7 @@ import (
 	"bufio"
 	"bytes"
 	"context"
+	"fmt"
 	"strings"
 	"time"
 
@@ -530,6 +531,10 @@ func ConvertClaudeResponseToGeminiNonStream(_ context.Context, modelName string,
 	return template
 }
 
+func GeminiTokenCount(ctx context.Context, count int64) string {
+	return fmt.Sprintf(`{"totalTokens":%d,"promptTokensDetails":[{"modality":"TEXT","tokenCount":%d}]}`, count, count)
+}
+
 // consolidateParts merges consecutive text parts and thinking parts to create a cleaner response.
 // This function processes the parts array to combine adjacent text elements and thinking elements
 // into single consolidated parts, which results in a more readable and efficient response structure.

internal/translator/claude/gemini/init.go

@@ -12,8 +12,9 @@ func init() {
 		Claude,
 		ConvertGeminiRequestToClaude,
 		interfaces.TranslateResponse{
-			Stream:    ConvertClaudeResponseToGemini,
-			NonStream: ConvertClaudeResponseToGeminiNonStream,
+			Stream:     ConvertClaudeResponseToGemini,
+			NonStream:  ConvertClaudeResponseToGeminiNonStream,
+			TokenCount: GeminiTokenCount,
 		},
 	)
 }

internal/translator/gemini-cli/claude/gemini-cli_claude_response.go

@@ -376,3 +376,7 @@ func ConvertGeminiCLIResponseToClaudeNonStream(_ context.Context, _ string, orig
 	}
 	return string(encoded)
 }
+
+func ClaudeTokenCount(ctx context.Context, count int64) string {
+	return fmt.Sprintf(`{"input_tokens":%d}`, count)
+}

internal/translator/gemini-cli/claude/init.go

@@ -12,8 +12,9 @@ func init() {
 		GeminiCLI,
 		ConvertClaudeRequestToCLI,
 		interfaces.TranslateResponse{
-			Stream:    ConvertGeminiCLIResponseToClaude,
-			NonStream: ConvertGeminiCLIResponseToClaudeNonStream,
+			Stream:     ConvertGeminiCLIResponseToClaude,
+			NonStream:  ConvertGeminiCLIResponseToClaudeNonStream,
+			TokenCount: ClaudeTokenCount,
 		},
 	)
 }

internal/translator/gemini-cli/gemini/gemini_gemini-cli_request.go

@@ -7,6 +7,7 @@ package gemini
 
 import (
 	"context"
+	"fmt"
 
 	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
@@ -74,3 +75,7 @@ func ConvertGeminiCliRequestToGeminiNonStream(_ context.Context, _ string, origi
 	}
 	return string(rawJSON)
 }
+
+func GeminiTokenCount(ctx context.Context, count int64) string {
+	return fmt.Sprintf(`{"totalTokens":%d,"promptTokensDetails":[{"modality":"TEXT","tokenCount":%d}]}`, count, count)
+}

internal/translator/gemini-cli/gemini/init.go

@@ -12,8 +12,9 @@ func init() {
 		GeminiCLI,
 		ConvertGeminiRequestToGeminiCLI,
 		interfaces.TranslateResponse{
-			Stream:    ConvertGeminiCliRequestToGemini,
-			NonStream: ConvertGeminiCliRequestToGeminiNonStream,
+			Stream:     ConvertGeminiCliRequestToGemini,
+			NonStream:  ConvertGeminiCliRequestToGeminiNonStream,
+			TokenCount: GeminiTokenCount,
 		},
 	)
 }

internal/translator/gemini/claude/gemini_claude_response.go

@@ -370,3 +370,7 @@ func ConvertGeminiResponseToClaudeNonStream(_ context.Context, _ string, origina
 	}
 	return string(encoded)
 }
+
+func ClaudeTokenCount(ctx context.Context, count int64) string {
+	return fmt.Sprintf(`{"input_tokens":%d}`, count)
+}

internal/translator/gemini/claude/init.go

@@ -12,8 +12,9 @@ func init() {
 		Gemini,
 		ConvertClaudeRequestToGemini,
 		interfaces.TranslateResponse{
-			Stream:    ConvertGeminiResponseToClaude,
-			NonStream: ConvertGeminiResponseToClaudeNonStream,
+			Stream:     ConvertGeminiResponseToClaude,
+			NonStream:  ConvertGeminiResponseToClaudeNonStream,
+			TokenCount: ClaudeTokenCount,
 		},
 	)
 }

internal/translator/gemini/gemini-cli/gemini_gemini-cli_response.go

@@ -7,6 +7,8 @@ package geminiCLI
 import (
 	"bytes"
 	"context"
+	"fmt"
+
 	"github.com/tidwall/sjson"
 )
 
@@ -47,3 +49,7 @@ func ConvertGeminiResponseToGeminiCLINonStream(_ context.Context, _ string, orig
 	rawJSON, _ = sjson.SetRawBytes([]byte(json), "response", rawJSON)
 	return string(rawJSON)
 }
+
+func GeminiCLITokenCount(ctx context.Context, count int64) string {
+	return fmt.Sprintf(`{"totalTokens":%d,"promptTokensDetails":[{"modality":"TEXT","tokenCount":%d}]}`, count, count)
+}

internal/translator/gemini/gemini-cli/init.go

@@ -12,8 +12,9 @@ func init() {
 		Gemini,
 		ConvertGeminiCLIRequestToGemini,
 		interfaces.TranslateResponse{
-			Stream:    ConvertGeminiResponseToGeminiCLI,
-			NonStream: ConvertGeminiResponseToGeminiCLINonStream,
+			Stream:     ConvertGeminiResponseToGeminiCLI,
+			NonStream:  ConvertGeminiResponseToGeminiCLINonStream,
+			TokenCount: GeminiCLITokenCount,
 		},
 	)
 }

internal/translator/gemini/gemini/gemini_gemini_response.go

@@ -3,6 +3,7 @@ package gemini
 import (
 	"bytes"
 	"context"
+	"fmt"
 )
 
 // PassthroughGeminiResponseStream forwards Gemini responses unchanged.
@@ -22,3 +23,7 @@ func PassthroughGeminiResponseStream(_ context.Context, _ string, originalReques
 func PassthroughGeminiResponseNonStream(_ context.Context, _ string, originalRequestRawJSON, requestRawJSON, rawJSON []byte, _ *any) string {
 	return string(rawJSON)
 }
+
+func GeminiTokenCount(ctx context.Context, count int64) string {
+	return fmt.Sprintf(`{"totalTokens":%d,"promptTokensDetails":[{"modality":"TEXT","tokenCount":%d}]}`, count, count)
+}

internal/translator/gemini/gemini/init.go

@@ -14,8 +14,9 @@ func init() {
 		Gemini,
 		ConvertGeminiRequestToGemini,
 		interfaces.TranslateResponse{
-			Stream:    PassthroughGeminiResponseStream,
-			NonStream: PassthroughGeminiResponseNonStream,
+			Stream:     PassthroughGeminiResponseStream,
+			NonStream:  PassthroughGeminiResponseNonStream,
+			TokenCount: GeminiTokenCount,
 		},
 	)
 }

sdk/translator/registry.go

@@ -91,6 +91,19 @@ func (r *Registry) TranslateNonStream(ctx context.Context, from, to Format, mode
 	return string(rawJSON)
 }
 
+// TranslateNonStream applies the registered non-stream response translator.
+func (r *Registry) TranslateTokenCount(ctx context.Context, from, to Format, count int64, rawJSON []byte) string {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+
+	if byTarget, ok := r.responses[to]; ok {
+		if fn, isOk := byTarget[from]; isOk && fn.TokenCount != nil {
+			return fn.TokenCount(ctx, count)
+		}
+	}
+	return string(rawJSON)
+}
+
 var defaultRegistry = NewRegistry()
 
 // Default exposes the package-level registry for shared use.
@@ -122,3 +135,8 @@ func TranslateStream(ctx context.Context, from, to Format, model string, origina
 func TranslateNonStream(ctx context.Context, from, to Format, model string, originalRequestRawJSON, requestRawJSON, rawJSON []byte, param *any) string {
 	return defaultRegistry.TranslateNonStream(ctx, from, to, model, originalRequestRawJSON, requestRawJSON, rawJSON, param)
 }
+
+// TranslateTokenCount is a helper on the default registry.
+func TranslateTokenCount(ctx context.Context, from, to Format, count int64, rawJSON []byte) string {
+	return defaultRegistry.TranslateTokenCount(ctx, from, to, count, rawJSON)
+}

sdk/translator/types.go

@@ -11,8 +11,11 @@ type ResponseStreamTransform func(ctx context.Context, model string, originalReq
 // ResponseNonStreamTransform converts non-stream responses between schemas.
 type ResponseNonStreamTransform func(ctx context.Context, model string, originalRequestRawJSON, requestRawJSON, rawJSON []byte, param *any) string
 
+type ResponseTokenCountTransform func(ctx context.Context, count int64) string
+
 // ResponseTransform groups streaming and non-streaming transforms.
 type ResponseTransform struct {
-	Stream    ResponseStreamTransform
-	NonStream ResponseNonStreamTransform
+	Stream     ResponseStreamTransform
+	NonStream  ResponseNonStreamTransform
+	TokenCount ResponseTokenCountTransform
 }