feat: add OpenRouter providerv0.15.0

16 files changed, 463 insertions, 69 deletions

diff --git a/internal/appconfig/config.go b/internal/appconfig/config.go
index 96ac300..e5a8d5f 100644
--- a/internal/appconfig/config.go
+++ b/internal/appconfig/config.go
@@ -56,8 +56,12 @@ type App struct {
 	OpenAIModel   string `json:"openai_model" toml:"openai_model"`
 	// Default temperature for OpenAI requests (nil means use provider default)
 	OpenAITemperature *float64 `json:"openai_temperature" toml:"openai_temperature"`
-	OllamaBaseURL     string   `json:"ollama_base_url" toml:"ollama_base_url"`
-	OllamaModel       string   `json:"ollama_model" toml:"ollama_model"`
+	OpenRouterBaseURL string   `json:"openrouter_base_url" toml:"openrouter_base_url"`
+	OpenRouterModel   string   `json:"openrouter_model" toml:"openrouter_model"`
+	// Default temperature for OpenRouter requests (nil means use provider default)
+	OpenRouterTemperature *float64 `json:"openrouter_temperature" toml:"openrouter_temperature"`
+	OllamaBaseURL         string   `json:"ollama_base_url" toml:"ollama_base_url"`
+	OllamaModel           string   `json:"ollama_model" toml:"ollama_model"`
 	// Default temperature for Ollama requests (nil means use provider default)
 	OllamaTemperature *float64 `json:"ollama_temperature" toml:"ollama_temperature"`
 	CopilotBaseURL    string   `json:"copilot_base_url" toml:"copilot_base_url"`
@@ -228,6 +232,7 @@ type fileConfig struct {
 	Chat       sectionChat       `toml:"chat"`
 	Provider   sectionProvider   `toml:"provider"`
 	OpenAI     sectionOpenAI     `toml:"openai"`
+	OpenRouter sectionOpenRouter `toml:"openrouter"`
 	Copilot    sectionCopilot    `toml:"copilot"`
 	Ollama     sectionOllama     `toml:"ollama"`
 	Prompts    sectionPrompts    `toml:"prompts"`
@@ -308,6 +313,12 @@ func (s sectionOpenAI) resolvedModel() string {
 	return model
 }
 
+type sectionOpenRouter struct {
+	Model       string   `toml:"model"`
+	BaseURL     string   `toml:"base_url"`
+	Temperature *float64 `toml:"temperature"`
+}
+
 type sectionCopilot struct {
 	Model       string   `toml:"model"`
 	BaseURL     string   `toml:"base_url"`
@@ -445,6 +456,16 @@ func (fc *fileConfig) toApp() App {
 		out.mergeProviderFields(&tmp)
 	}
 
+	// openrouter
+	if (fc.OpenRouter != sectionOpenRouter{}) || fc.OpenRouter.Temperature != nil {
+		tmp := App{
+			OpenRouterBaseURL:     fc.OpenRouter.BaseURL,
+			OpenRouterModel:       fc.OpenRouter.Model,
+			OpenRouterTemperature: fc.OpenRouter.Temperature,
+		}
+		out.mergeProviderFields(&tmp)
+	}
+
 	// copilot
 	if (fc.Copilot != sectionCopilot{}) || fc.Copilot.Temperature != nil {
 		tmp := App{
@@ -1025,6 +1046,15 @@ func (a *App) mergeProviderFields(other *App) {
 	if other.OpenAITemperature != nil { // allow explicit 0.0
 		a.OpenAITemperature = other.OpenAITemperature
 	}
+	if s := strings.TrimSpace(other.OpenRouterBaseURL); s != "" {
+		a.OpenRouterBaseURL = s
+	}
+	if s := strings.TrimSpace(other.OpenRouterModel); s != "" {
+		a.OpenRouterModel = s
+	}
+	if other.OpenRouterTemperature != nil { // allow explicit 0.0
+		a.OpenRouterTemperature = other.OpenRouterTemperature
+	}
 	if s := strings.TrimSpace(other.OllamaBaseURL); s != "" {
 		a.OllamaBaseURL = s
 	}
@@ -1223,6 +1253,19 @@ func loadFromEnv(logger *log.Logger) *App {
 		any = true
 	}
 
+	if s := getenv("HEXAI_OPENROUTER_BASE_URL"); s != "" {
+		out.OpenRouterBaseURL = s
+		any = true
+	}
+	if model, ok := pickModel("openrouter", getenv("HEXAI_OPENROUTER_MODEL")); ok {
+		out.OpenRouterModel = model
+		any = true
+	}
+	if f, ok := parseFloatPtr("HEXAI_OPENROUTER_TEMPERATURE"); ok {
+		out.OpenRouterTemperature = f
+		any = true
+	}
+
 	if s := getenv("HEXAI_OLLAMA_BASE_URL"); s != "" {
 		out.OllamaBaseURL = s
 		any = true
diff --git a/internal/hexailsp/run.go b/internal/hexailsp/run.go
index 0e383ac..f0ab404 100644
--- a/internal/hexailsp/run.go
+++ b/internal/hexailsp/run.go
@@ -104,28 +104,36 @@ func buildClientIfNil(cfg appconfig.App, client llm.Client) llm.Client {
 		return client
 	}
 	llmCfg := llm.Config{
-		Provider:           cfg.Provider,
-		OpenAIBaseURL:      cfg.OpenAIBaseURL,
-		OpenAIModel:        cfg.OpenAIModel,
-		OpenAITemperature:  cfg.OpenAITemperature,
-		OllamaBaseURL:      cfg.OllamaBaseURL,
-		OllamaModel:        cfg.OllamaModel,
-		OllamaTemperature:  cfg.OllamaTemperature,
-		CopilotBaseURL:     cfg.CopilotBaseURL,
-		CopilotModel:       cfg.CopilotModel,
-		CopilotTemperature: cfg.CopilotTemperature,
+		Provider:              cfg.Provider,
+		OpenAIBaseURL:         cfg.OpenAIBaseURL,
+		OpenAIModel:           cfg.OpenAIModel,
+		OpenAITemperature:     cfg.OpenAITemperature,
+		OpenRouterBaseURL:     cfg.OpenRouterBaseURL,
+		OpenRouterModel:       cfg.OpenRouterModel,
+		OpenRouterTemperature: cfg.OpenRouterTemperature,
+		OllamaBaseURL:         cfg.OllamaBaseURL,
+		OllamaModel:           cfg.OllamaModel,
+		OllamaTemperature:     cfg.OllamaTemperature,
+		CopilotBaseURL:        cfg.CopilotBaseURL,
+		CopilotModel:          cfg.CopilotModel,
+		CopilotTemperature:    cfg.CopilotTemperature,
 	}
 	// Prefer HEXAI_OPENAI_API_KEY; fall back to OPENAI_API_KEY
 	oaKey := os.Getenv("HEXAI_OPENAI_API_KEY")
 	if strings.TrimSpace(oaKey) == "" {
 		oaKey = os.Getenv("OPENAI_API_KEY")
 	}
+	// Prefer HEXAI_OPENROUTER_API_KEY; fall back to OPENROUTER_API_KEY
+	orKey := os.Getenv("HEXAI_OPENROUTER_API_KEY")
+	if strings.TrimSpace(orKey) == "" {
+		orKey = os.Getenv("OPENROUTER_API_KEY")
+	}
 	// Prefer HEXAI_COPILOT_API_KEY; fall back to COPILOT_API_KEY
 	cpKey := os.Getenv("HEXAI_COPILOT_API_KEY")
 	if strings.TrimSpace(cpKey) == "" {
 		cpKey = os.Getenv("COPILOT_API_KEY")
 	}
-	if c, err := llm.NewFromConfig(llmCfg, oaKey, cpKey); err != nil {
+	if c, err := llm.NewFromConfig(llmCfg, oaKey, orKey, cpKey); err != nil {
 		logging.Logf("lsp ", "llm disabled: %v", err)
 		return nil
 	} else {
diff --git a/internal/llm/openai.go b/internal/llm/openai.go
index 8a0d6d7..c284bb3 100644
--- a/internal/llm/openai.go
+++ b/internal/llm/openai.go
@@ -106,7 +106,7 @@ func (c openAIClient) Chat(ctx context.Context, messages []Message, opts ...Requ
 	}
 	start := time.Now()
 	c.logStart(false, o, messages)
-	req := buildOAChatRequest(o, messages, c.defaultTemperature, false)
+	req := buildOAChatRequest(o, messages, c.defaultTemperature, false, "llm/openai ")
 	body, err := json.Marshal(req)
 	if err != nil {
 		c.logf("marshal error: %v", err)
@@ -122,10 +122,10 @@ func (c openAIClient) Chat(ctx context.Context, messages []Message, opts ...Requ
 		return "", err
 	}
 	defer resp.Body.Close()
-	if err := handleOpenAINon2xx(resp, start); err != nil {
+	if err := handleOpenAINon2xx(resp, start, "llm/openai ", "openai"); err != nil {
 		return "", err
 	}
-	out, err := decodeOpenAIChat(resp, start)
+	out, err := decodeOpenAIChat(resp, start, "llm/openai ")
 	if err != nil {
 		return "", err
 	}
@@ -157,7 +157,7 @@ func (c openAIClient) ChatStream(ctx context.Context, messages []Message, onDelt
 	}
 	start := time.Now()
 	c.logStart(true, o, messages)
-	req := buildOAChatRequest(o, messages, c.defaultTemperature, true)
+	req := buildOAChatRequest(o, messages, c.defaultTemperature, true, "llm/openai ")
 	body, err := json.Marshal(req)
 	if err != nil {
 		c.logf("marshal error: %v", err)
@@ -173,11 +173,11 @@ func (c openAIClient) ChatStream(ctx context.Context, messages []Message, onDelt
 		return err
 	}
 	defer resp.Body.Close()
-	if err := handleOpenAINon2xx(resp, start); err != nil {
+	if err := handleOpenAINon2xx(resp, start, "llm/openai ", "openai"); err != nil {
 		return err
 	}
 
-	if err := parseOpenAIStream(resp, start, onDelta); err != nil {
+	if err := parseOpenAIStream(resp, start, onDelta, "llm/openai ", "openai"); err != nil {
 		return err
 	}
 	logging.Logf("llm/openai ", "stream end duration=%s", time.Since(start))
@@ -196,7 +196,7 @@ func (c openAIClient) logStart(stream bool, o Options, messages []Message) {
 	c.chatLogger.LogStart(stream, o.Model, o.Temperature, o.MaxTokens, o.Stop, logMessages)
 }
 
-func buildOAChatRequest(o Options, messages []Message, defaultTemp *float64, stream bool) oaChatRequest {
+func buildOAChatRequest(o Options, messages []Message, defaultTemp *float64, stream bool, logPrefix string) oaChatRequest {
 	req := oaChatRequest{Model: o.Model, Stream: stream}
 	req.Messages = make([]oaMessage, len(messages))
 	for i, m := range messages {
@@ -223,7 +223,7 @@ func buildOAChatRequest(o Options, messages []Message, defaultTemp *float64, str
 		if req.Temperature == nil || *req.Temperature != 1.0 {
 			t := 1.0
 			req.Temperature = &t
-			logging.Logf("llm/openai ", "forcing temperature=1.0 for model=%s (gpt-5 constraint)", o.Model)
+			logging.Logf(logPrefix, "forcing temperature=1.0 for model=%s (gpt-5 constraint)", o.Model)
 		}
 	}
 	return req
@@ -262,30 +262,30 @@ func (c openAIClient) doJSONWithAccept(ctx context.Context, url string, body []b
 	return c.httpClient.Do(req)
 }
 
-func handleOpenAINon2xx(resp *http.Response, start time.Time) error {
+func handleOpenAINon2xx(resp *http.Response, start time.Time, logPrefix, provider string) error {
 	if resp.StatusCode >= 200 && resp.StatusCode < 300 {
 		return nil
 	}
 	var apiErr oaChatResponse
 	_ = json.NewDecoder(resp.Body).Decode(&apiErr)
 	if apiErr.Error != nil && apiErr.Error.Message != "" {
-		logging.Logf("llm/openai ", "%sapi error status=%d type=%s msg=%s duration=%s%s", logging.AnsiRed, resp.StatusCode, apiErr.Error.Type, apiErr.Error.Message, time.Since(start), logging.AnsiBase)
-		return fmt.Errorf("openai error: %s (status %d)", apiErr.Error.Message, resp.StatusCode)
+		logging.Logf(logPrefix, "%sapi error status=%d type=%s msg=%s duration=%s%s", logging.AnsiRed, resp.StatusCode, apiErr.Error.Type, apiErr.Error.Message, time.Since(start), logging.AnsiBase)
+		return fmt.Errorf("%s error: %s (status %d)", provider, apiErr.Error.Message, resp.StatusCode)
 	}
-	logging.Logf("llm/openai ", "%shttp non-2xx status=%d duration=%s%s", logging.AnsiRed, resp.StatusCode, time.Since(start), logging.AnsiBase)
-	return fmt.Errorf("openai http error: status %d", resp.StatusCode)
+	logging.Logf(logPrefix, "%shttp non-2xx status=%d duration=%s%s", logging.AnsiRed, resp.StatusCode, time.Since(start), logging.AnsiBase)
+	return fmt.Errorf("%s http error: status %d", provider, resp.StatusCode)
 }
 
-func decodeOpenAIChat(resp *http.Response, start time.Time) (oaChatResponse, error) {
+func decodeOpenAIChat(resp *http.Response, start time.Time, logPrefix string) (oaChatResponse, error) {
 	var out oaChatResponse
 	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
-		logging.Logf("llm/openai ", "%sdecode error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		logging.Logf(logPrefix, "%sdecode error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
 		return oaChatResponse{}, err
 	}
 	return out, nil
 }
 
-func parseOpenAIStream(resp *http.Response, start time.Time, onDelta func(string)) error {
+func parseOpenAIStream(resp *http.Response, start time.Time, onDelta func(string), logPrefix, provider string) error {
 	// Parse SSE: lines starting with "data: " containing JSON or [DONE]
 	scanner := bufio.NewScanner(resp.Body)
 	const maxBuf = 1024 * 1024
@@ -305,8 +305,8 @@ func parseOpenAIStream(resp *http.Response, start time.Time, onDelta func(string
 			continue
 		}
 		if chunk.Error != nil && chunk.Error.Message != "" {
-			logging.Logf("llm/openai ", "%sstream error: %s%s", logging.AnsiRed, chunk.Error.Message, logging.AnsiBase)
-			return fmt.Errorf("openai stream error: %s", chunk.Error.Message)
+			logging.Logf(logPrefix, "%sstream error: %s%s", logging.AnsiRed, chunk.Error.Message, logging.AnsiBase)
+			return fmt.Errorf("%s stream error: %s", provider, chunk.Error.Message)
 		}
 		for _, ch := range chunk.Choices {
 			if ch.Delta.Content != "" {
@@ -315,7 +315,7 @@ func parseOpenAIStream(resp *http.Response, start time.Time, onDelta func(string
 		}
 	}
 	if err := scanner.Err(); err != nil {
-		logging.Logf("llm/openai ", "%sstream read error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		logging.Logf(logPrefix, "%sstream read error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
 		return err
 	}
 	return nil
diff --git a/internal/llm/openai_http_test.go b/internal/llm/openai_http_test.go
index cb4bfcb..affcae9 100644
--- a/internal/llm/openai_http_test.go
+++ b/internal/llm/openai_http_test.go
@@ -60,7 +60,7 @@ func TestOpenAI_ChatStream_SSE(t *testing.T) {
 
 func TestHandleOpenAINon2xx_NoErrorBody(t *testing.T) {
 	resp := &http.Response{StatusCode: 500, Body: io.NopCloser(strings.NewReader("{}"))}
-	if err := handleOpenAINon2xx(resp, time.Now()); err == nil {
+	if err := handleOpenAINon2xx(resp, time.Now(), "llm/openai ", "openai"); err == nil {
 		t.Fatalf("expected http error")
 	}
 }
diff --git a/internal/llm/openai_request_test.go b/internal/llm/openai_request_test.go
index 001e3b7..d053031 100644
--- a/internal/llm/openai_request_test.go
+++ b/internal/llm/openai_request_test.go
@@ -9,13 +9,13 @@ func TestBuildOAChatRequest_MaxTokensKeyByModel(t *testing.T) {
 	msgs := []Message{{Role: "user", Content: "hi"}}
 	mt := 123
 	// Legacy model: use max_tokens
-	r1 := buildOAChatRequest(Options{Model: "gpt-4.1", MaxTokens: mt}, msgs, nil, false)
+	r1 := buildOAChatRequest(Options{Model: "gpt-4.1", MaxTokens: mt}, msgs, nil, false, "llm/test ")
 	b1, _ := json.Marshal(r1)
 	if !contains(string(b1), "max_tokens") || contains(string(b1), "max_completion_tokens") {
 		t.Fatalf("expected max_tokens only, got %s", string(b1))
 	}
 	// gpt-5 family: use max_completion_tokens
-	r2 := buildOAChatRequest(Options{Model: "gpt-5.0-preview", MaxTokens: mt}, msgs, nil, false)
+	r2 := buildOAChatRequest(Options{Model: "gpt-5.0-preview", MaxTokens: mt}, msgs, nil, false, "llm/test ")
 	b2, _ := json.Marshal(r2)
 	if !contains(string(b2), "max_completion_tokens") || contains(string(b2), "max_tokens\":") {
 		t.Fatalf("expected max_completion_tokens only, got %s", string(b2))
@@ -25,7 +25,7 @@ func TestBuildOAChatRequest_MaxTokensKeyByModel(t *testing.T) {
 func TestBuildOAChatRequest_TemperatureForcedForGpt5(t *testing.T) {
 	msgs := []Message{{Role: "user", Content: "hi"}}
 	// Explicit temp 0.2 → should be forced to 1.0 for gpt-5
-	r := buildOAChatRequest(Options{Model: "gpt-5.0", Temperature: 0.2, MaxTokens: 50}, msgs, nil, false)
+	r := buildOAChatRequest(Options{Model: "gpt-5.0", Temperature: 0.2, MaxTokens: 50}, msgs, nil, false, "llm/test ")
 	b, _ := json.Marshal(r)
 	if !contains(string(b), "\"temperature\":1") {
 		t.Fatalf("expected forced temperature 1.0 for gpt-5, got %s", string(b))
diff --git a/internal/llm/openai_temp_test.go b/internal/llm/openai_temp_test.go
index 7615117..3d71b94 100644
--- a/internal/llm/openai_temp_test.go
+++ b/internal/llm/openai_temp_test.go
@@ -5,7 +5,7 @@ import "testing"
 func TestNewFromConfig_DefaultTemp_ByModel(t *testing.T) {
 	// OpenAI, gpt-5.* → default temp 1.0 when not provided
 	cfg := Config{Provider: "openai", OpenAIModel: "gpt-5.0-preview"}
-	c, err := NewFromConfig(cfg, "key", "")
+	c, err := NewFromConfig(cfg, "key", "", "")
 	if err != nil {
 		t.Fatalf("new: %v", err)
 	}
@@ -18,7 +18,7 @@ func TestNewFromConfig_DefaultTemp_ByModel(t *testing.T) {
 	}
 	// OpenAI, gpt-4.* → default temp 0.2 when not provided
 	cfg2 := Config{Provider: "openai", OpenAIModel: "gpt-4.1"}
-	c2, err := NewFromConfig(cfg2, "key", "")
+	c2, err := NewFromConfig(cfg2, "key", "", "")
 	if err != nil {
 		t.Fatalf("new2: %v", err)
 	}
@@ -32,7 +32,7 @@ func TestNewFromConfig_DefaultTemp_UpgradeWhenGpt5AndDefault02(t *testing.T) {
 	// Simulate app-default of 0.2 while selecting a gpt-5 model: should upgrade to 1.0
 	v := 0.2
 	cfg := Config{Provider: "openai", OpenAIModel: "gpt-5.0", OpenAITemperature: &v}
-	c, err := NewFromConfig(cfg, "key", "")
+	c, err := NewFromConfig(cfg, "key", "", "")
 	if err != nil {
 		t.Fatalf("new: %v", err)
 	}
diff --git a/internal/llm/openrouter.go b/internal/llm/openrouter.go
new file mode 100644
index 0000000..f03844a
--- /dev/null
+++ b/internal/llm/openrouter.go
@@ -0,0 +1,168 @@
+// Summary: OpenRouter client implementation leveraging OpenAI-compatible helpers with provider-specific headers.
+package llm
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"strings"
+	"time"
+
+	"codeberg.org/snonux/hexai/internal/logging"
+)
+
+type openRouterClient struct {
+	httpClient         *http.Client
+	apiKey             string
+	baseURL            string
+	defaultModel       string
+	chatLogger         logging.ChatLogger
+	defaultTemperature *float64
+}
+
+func newOpenRouter(baseURL, model, apiKey string, defaultTemp *float64) Client {
+	if strings.TrimSpace(baseURL) == "" {
+		baseURL = "https://openrouter.ai/api/v1"
+	}
+	if strings.TrimSpace(model) == "" {
+		model = "openrouter/auto"
+	}
+	return openRouterClient{
+		httpClient:         &http.Client{Timeout: 30 * time.Second},
+		apiKey:             apiKey,
+		baseURL:            baseURL,
+		defaultModel:       model,
+		chatLogger:         logging.NewChatLogger("openrouter"),
+		defaultTemperature: defaultTemp,
+	}
+}
+
+func (c openRouterClient) Chat(ctx context.Context, messages []Message, opts ...RequestOption) (string, error) {
+	if strings.TrimSpace(c.apiKey) == "" {
+		return nilStringErr("missing OpenRouter API key")
+	}
+	o := Options{Model: c.defaultModel}
+	for _, opt := range opts {
+		opt(&o)
+	}
+	if strings.TrimSpace(o.Model) == "" {
+		o.Model = c.defaultModel
+	}
+	start := time.Now()
+	c.logStart(false, o, messages)
+	req := buildOAChatRequest(o, messages, c.defaultTemperature, false, "llm/openrouter ")
+	body, err := json.Marshal(req)
+	if err != nil {
+		c.logf("marshal error: %v", err)
+		return "", err
+	}
+	endpoint := strings.TrimRight(c.baseURL, "/") + "/chat/completions"
+	logging.Logf("llm/openrouter ", "POST %s", endpoint)
+	resp, err := c.doJSON(ctx, endpoint, body)
+	if err != nil {
+		logging.Logf("llm/openrouter ", "%shttp error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		return "", err
+	}
+	defer resp.Body.Close()
+	if err := handleOpenAINon2xx(resp, start, "llm/openrouter ", "openrouter"); err != nil {
+		return "", err
+	}
+	out, err := decodeOpenAIChat(resp, start, "llm/openrouter ")
+	if err != nil {
+		return "", err
+	}
+	if len(out.Choices) == 0 {
+		logging.Logf("llm/openrouter ", "%sno choices returned duration=%s%s", logging.AnsiRed, time.Since(start), logging.AnsiBase)
+		return "", errors.New("openrouter: no choices returned")
+	}
+	content := out.Choices[0].Message.Content
+	logging.Logf("llm/openrouter ", "success choice=0 finish=%s size=%d preview=%s%s%s duration=%s", out.Choices[0].FinishReason, len(content), logging.AnsiGreen, logging.PreviewForLog(content), logging.AnsiBase, time.Since(start))
+	return content, nil
+}
+
+func (c openRouterClient) Name() string         { return "openrouter" }
+func (c openRouterClient) DefaultModel() string { return c.defaultModel }
+
+func (c openRouterClient) ChatStream(ctx context.Context, messages []Message, onDelta func(string), opts ...RequestOption) error {
+	if strings.TrimSpace(c.apiKey) == "" {
+		return errors.New("missing OpenRouter API key")
+	}
+	o := Options{Model: c.defaultModel}
+	for _, opt := range opts {
+		opt(&o)
+	}
+	if strings.TrimSpace(o.Model) == "" {
+		o.Model = c.defaultModel
+	}
+	start := time.Now()
+	c.logStart(true, o, messages)
+	req := buildOAChatRequest(o, messages, c.defaultTemperature, true, "llm/openrouter ")
+	body, err := json.Marshal(req)
+	if err != nil {
+		c.logf("marshal error: %v", err)
+		return err
+	}
+	endpoint := strings.TrimRight(c.baseURL, "/") + "/chat/completions"
+	logging.Logf("llm/openrouter ", "POST %s (stream)", endpoint)
+	resp, err := c.doJSONWithAccept(ctx, endpoint, body, "text/event-stream")
+	if err != nil {
+		logging.Logf("llm/openrouter ", "%shttp error after %s: %v%s", logging.AnsiRed, time.Since(start), err, logging.AnsiBase)
+		return err
+	}
+	defer resp.Body.Close()
+	if err := handleOpenAINon2xx(resp, start, "llm/openrouter ", "openrouter"); err != nil {
+		return err
+	}
+	if err := parseOpenAIStream(resp, start, onDelta, "llm/openrouter ", "openrouter"); err != nil {
+		return err
+	}
+	logging.Logf("llm/openrouter ", "stream end duration=%s", time.Since(start))
+	return nil
+}
+
+func (c openRouterClient) logf(format string, args ...any) {
+	logging.Logf("llm/openrouter ", format, args...)
+}
+
+func (c openRouterClient) logStart(stream bool, o Options, messages []Message) {
+	logMessages := make([]struct{ Role, Content string }, len(messages))
+	for i, m := range messages {
+		logMessages[i] = struct{ Role, Content string }{m.Role, m.Content}
+	}
+	c.chatLogger.LogStart(stream, o.Model, o.Temperature, o.MaxTokens, o.Stop, logMessages)
+}
+
+func (c openRouterClient) doJSON(ctx context.Context, url string, body []byte) (*http.Response, error) {
+	headers := map[string]string{
+		"Authorization": "Bearer " + c.apiKey,
+		"HTTP-Referer":  "https://github.com/snonux/hexai",
+		"X-Title":       "Hexai",
+	}
+	return c.doJSONWithHeaders(ctx, url, body, headers, "")
+}
+
+func (c openRouterClient) doJSONWithAccept(ctx context.Context, url string, body []byte, accept string) (*http.Response, error) {
+	headers := map[string]string{
+		"Authorization": "Bearer " + c.apiKey,
+		"HTTP-Referer":  "https://github.com/snonux/hexai",
+		"X-Title":       "Hexai",
+	}
+	return c.doJSONWithHeaders(ctx, url, body, headers, accept)
+}
+
+func (c openRouterClient) doJSONWithHeaders(ctx context.Context, url string, body []byte, headers map[string]string, accept string) (*http.Response, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	if strings.TrimSpace(accept) != "" {
+		req.Header.Set("Accept", accept)
+	}
+	for k, v := range headers {
+		req.Header.Set(k, v)
+	}
+	return c.httpClient.Do(req)
+}
diff --git a/internal/llm/openrouter_test.go b/internal/llm/openrouter_test.go
new file mode 100644
index 0000000..2a07be0
--- /dev/null
+++ b/internal/llm/openrouter_test.go
@@ -0,0 +1,125 @@
+package llm
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	"codeberg.org/snonux/hexai/internal/logging"
+)
+
+func TestOpenRouter_Chat_SendsHeadersAndBody(t *testing.T) {
+	if os.Getenv("HEXAI_TEST_SKIP_NET") == "1" {
+		t.Skip("skip network-bound tests in restricted environments")
+	}
+	var capturedHeaders http.Header
+	var capturedBody []byte
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		capturedHeaders = r.Header.Clone()
+		body, err := io.ReadAll(r.Body)
+		if err != nil {
+			t.Fatalf("read body: %v", err)
+		}
+		capturedBody = append([]byte(nil), body...)
+		_ = json.NewEncoder(w).Encode(map[string]any{
+			"choices": []map[string]any{
+				{"index": 0, "message": map[string]string{"role": "assistant", "content": "ack"}},
+			},
+		})
+	}))
+	defer srv.Close()
+
+	c := newOpenRouter(srv.URL, "anthropic/claude-test", "KEY", f64p(0.2)).(openRouterClient)
+	c.httpClient = srv.Client()
+	out, err := c.Chat(context.Background(), []Message{{Role: "user", Content: "ping"}})
+	if err != nil {
+		t.Fatalf("chat returned error: %v", err)
+	}
+	if out != "ack" {
+		t.Fatalf("unexpected response: %q", out)
+	}
+	if capturedHeaders.Get("Authorization") != "Bearer KEY" {
+		t.Fatalf("missing auth header: %#v", capturedHeaders)
+	}
+	if capturedHeaders.Get("HTTP-Referer") != "https://github.com/snonux/hexai" {
+		t.Fatalf("missing referer header: %#v", capturedHeaders)
+	}
+	if capturedHeaders.Get("X-Title") != "Hexai" {
+		t.Fatalf("missing title header: %#v", capturedHeaders)
+	}
+
+	var req oaChatRequest
+	if err := json.Unmarshal(capturedBody, &req); err != nil {
+		t.Fatalf("unmarshal request: %v", err)
+	}
+	if req.Model != "anthropic/claude-test" {
+		t.Fatalf("unexpected model: %q", req.Model)
+	}
+	if len(req.Messages) != 1 || req.Messages[0].Role != "user" || req.Messages[0].Content != "ping" {
+		t.Fatalf("unexpected messages: %#v", req.Messages)
+	}
+}
+
+func TestOpenRouter_ChatStream_SendsHeaders(t *testing.T) {
+	if os.Getenv("HEXAI_TEST_SKIP_NET") == "1" {
+		t.Skip("skip network-bound tests in restricted environments")
+	}
+	var acceptHeader string
+	var referer string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		acceptHeader = r.Header.Get("Accept")
+		referer = r.Header.Get("HTTP-Referer")
+		w.Header().Set("Content-Type", "text/event-stream")
+		io.WriteString(w, "data: {\"choices\":[{\"delta\":{\"content\":\"hi\"}}]}\n\n")
+		io.WriteString(w, "data: [DONE]\n")
+	}))
+	defer srv.Close()
+
+	c := newOpenRouter(srv.URL, "anthropic/claude-test", "KEY", f64p(0.2)).(openRouterClient)
+	c.httpClient = srv.Client()
+	var got string
+	err := c.ChatStream(context.Background(), []Message{{Role: "user", Content: "ping"}}, func(s string) { got += s })
+	if err != nil {
+		t.Fatalf("chat stream error: %v", err)
+	}
+	if got != "hi" {
+		t.Fatalf("expected stream output 'hi', got %q", got)
+	}
+	if acceptHeader != "text/event-stream" {
+		t.Fatalf("unexpected Accept header: %q", acceptHeader)
+	}
+	if referer != "https://github.com/snonux/hexai" {
+		t.Fatalf("missing referer header in stream: %q", referer)
+	}
+}
+
+func TestOpenRouter_Chat_MissingKey(t *testing.T) {
+	c := newOpenRouter("http://example", "anthropic/claude-test", "", f64p(0.2)).(openRouterClient)
+	if _, err := c.Chat(context.Background(), []Message{{Role: "user", Content: "ping"}}); err == nil {
+		t.Fatalf("expected error for missing api key")
+	}
+}
+
+func TestOpenRouter_DefaultsAndMetadata(t *testing.T) {
+	logger := log.New(io.Discard, "", 0)
+	logging.Bind(logger)
+	c := newOpenRouter("", "", "KEY", nil).(openRouterClient)
+	if c.baseURL != "https://openrouter.ai/api/v1" {
+		t.Fatalf("default baseURL mismatch: %s", c.baseURL)
+	}
+	if c.defaultModel != "openrouter/auto" {
+		t.Fatalf("default model mismatch: %s", c.defaultModel)
+	}
+	if name := c.Name(); name != "openrouter" {
+		t.Fatalf("Name() = %s", name)
+	}
+	if model := c.DefaultModel(); model != "openrouter/auto" {
+		t.Fatalf("DefaultModel() = %s", model)
+	}
+	c.logf("smoke")
+}
diff --git a/internal/llm/provider.go b/internal/llm/provider.go
index 84efaf9..b2c47e4 100644
--- a/internal/llm/provider.go
+++ b/internal/llm/provider.go
@@ -69,6 +69,10 @@ type Config struct {
 	OpenAIBaseURL     string
 	OpenAIModel       string
 	OpenAITemperature *float64
+	// OpenRouter options
+	OpenRouterBaseURL     string
+	OpenRouterModel       string
+	OpenRouterTemperature *float64
 	// Ollama options
 	OllamaBaseURL     string
 	OllamaModel       string
@@ -82,7 +86,7 @@ type Config struct {
 // NewFromConfig creates an LLM client using only the supplied configuration.
 // The OpenAI API key is supplied separately and may be read from the environment
 // by the caller; other environment-based configuration is not used.
-func NewFromConfig(cfg Config, openAIAPIKey, copilotAPIKey string) (Client, error) {
+func NewFromConfig(cfg Config, openAIAPIKey, openRouterAPIKey, copilotAPIKey string) (Client, error) {
 	p := strings.ToLower(strings.TrimSpace(cfg.Provider))
 	if p == "" {
 		p = "openai"
@@ -112,6 +116,15 @@ func NewFromConfig(cfg Config, openAIAPIKey, copilotAPIKey string) (Client, erro
 			cfg.OpenAITemperature = &v
 		}
 		return newOpenAI(cfg.OpenAIBaseURL, cfg.OpenAIModel, openAIAPIKey, cfg.OpenAITemperature), nil
+	case "openrouter":
+		if strings.TrimSpace(openRouterAPIKey) == "" {
+			return nil, errors.New("missing OPENROUTER_API_KEY for provider openrouter")
+		}
+		if cfg.OpenRouterTemperature == nil {
+			t := 0.2
+			cfg.OpenRouterTemperature = &t
+		}
+		return newOpenRouter(cfg.OpenRouterBaseURL, cfg.OpenRouterModel, openRouterAPIKey, cfg.OpenRouterTemperature), nil
 	case "ollama":
 		if cfg.OllamaTemperature == nil {
 			t := 0.2
diff --git a/internal/llm/provider_more2_test.go b/internal/llm/provider_more2_test.go
index 465be82..e001e5c 100644
--- a/internal/llm/provider_more2_test.go
+++ b/internal/llm/provider_more2_test.go
@@ -5,7 +5,7 @@ import "testing"
 func TestNewFromConfig_Copilot(t *testing.T) {
 	t.Setenv("COPILOT_API_KEY", "x")
 	cfg := Config{Provider: "copilot", CopilotModel: "small"}
-	c, err := NewFromConfig(cfg, "", "x")
+	c, err := NewFromConfig(cfg, "", "", "x")
 	if err != nil || c == nil {
 		t.Fatalf("copilot provider failed: %v %v", c, err)
 	}
diff --git a/internal/llm/provider_more_test.go b/internal/llm/provider_more_test.go
index d7469af..eff99e6 100644
--- a/internal/llm/provider_more_test.go
+++ b/internal/llm/provider_more_test.go
@@ -16,13 +16,13 @@ func TestWithOptions_Apply(t *testing.T) {
 func TestNewFromConfig_Success_OpenAI_And_Copilot(t *testing.T) {
 	// OpenAI success
 	oc := Config{Provider: "openai", OpenAIBaseURL: "http://x", OpenAIModel: "gpt"}
-	c, err := NewFromConfig(oc, "KEY", "")
+	c, err := NewFromConfig(oc, "KEY", "", "")
 	if err != nil || c == nil || c.Name() != "openai" || c.DefaultModel() == "" {
 		t.Fatalf("openai new: %v %v", c, err)
 	}
 	// Copilot success
 	cc := Config{Provider: "copilot", CopilotBaseURL: "http://x", CopilotModel: "gpt-4o-mini"}
-	c2, err := NewFromConfig(cc, "", "KEY")
+	c2, err := NewFromConfig(cc, "", "", "KEY")
 	if err != nil || c2 == nil || c2.Name() != "copilot" || c2.DefaultModel() == "" {
 		t.Fatalf("copilot new: %v %v", c2, err)
 	}
diff --git a/internal/llm/provider_test.go b/internal/llm/provider_test.go
index 29e2514..2c0d69c 100644
--- a/internal/llm/provider_test.go
+++ b/internal/llm/provider_test.go
@@ -7,15 +7,15 @@ import (
 
 func TestNewFromConfig_DefaultsAndErrors(t *testing.T) {
 	// Unknown provider
-	if _, err := NewFromConfig(Config{Provider: "bogus"}, "", ""); err == nil {
+	if _, err := NewFromConfig(Config{Provider: "bogus"}, "", "", ""); err == nil {
 		t.Fatalf("expected error for unknown provider")
 	}
 	// OpenAI missing key
-	if _, err := NewFromConfig(Config{Provider: "openai", OpenAIModel: "g"}, "", ""); err == nil {
+	if _, err := NewFromConfig(Config{Provider: "openai", OpenAIModel: "g"}, "", "", ""); err == nil {
 		t.Fatalf("expected key error")
 	}
 	// Copilot missing key
-	if _, err := NewFromConfig(Config{Provider: "copilot", CopilotModel: "m"}, "", ""); err == nil {
+	if _, err := NewFromConfig(Config{Provider: "copilot", CopilotModel: "m"}, "", "", ""); err == nil {
 		t.Fatalf("expected key error")
 	}
 }
diff --git a/internal/llmutils/client.go b/internal/llmutils/client.go
index 9bd39ee..2f3da55 100644
--- a/internal/llmutils/client.go
+++ b/internal/llmutils/client.go
@@ -11,24 +11,31 @@ import (
 // NewClientFromApp builds an llm.Client using app config and environment keys.
 func NewClientFromApp(cfg appconfig.App) (llm.Client, error) {
 	llmCfg := llm.Config{
-		Provider:           cfg.Provider,
-		OpenAIBaseURL:      cfg.OpenAIBaseURL,
-		OpenAIModel:        cfg.OpenAIModel,
-		OpenAITemperature:  cfg.OpenAITemperature,
-		OllamaBaseURL:      cfg.OllamaBaseURL,
-		OllamaModel:        cfg.OllamaModel,
-		OllamaTemperature:  cfg.OllamaTemperature,
-		CopilotBaseURL:     cfg.CopilotBaseURL,
-		CopilotModel:       cfg.CopilotModel,
-		CopilotTemperature: cfg.CopilotTemperature,
+		Provider:              cfg.Provider,
+		OpenAIBaseURL:         cfg.OpenAIBaseURL,
+		OpenAIModel:           cfg.OpenAIModel,
+		OpenAITemperature:     cfg.OpenAITemperature,
+		OpenRouterBaseURL:     cfg.OpenRouterBaseURL,
+		OpenRouterModel:       cfg.OpenRouterModel,
+		OpenRouterTemperature: cfg.OpenRouterTemperature,
+		OllamaBaseURL:         cfg.OllamaBaseURL,
+		OllamaModel:           cfg.OllamaModel,
+		OllamaTemperature:     cfg.OllamaTemperature,
+		CopilotBaseURL:        cfg.CopilotBaseURL,
+		CopilotModel:          cfg.CopilotModel,
+		CopilotTemperature:    cfg.CopilotTemperature,
 	}
 	oaKey := os.Getenv("HEXAI_OPENAI_API_KEY")
 	if strings.TrimSpace(oaKey) == "" {
 		oaKey = os.Getenv("OPENAI_API_KEY")
 	}
+	orKey := os.Getenv("HEXAI_OPENROUTER_API_KEY")
+	if strings.TrimSpace(orKey) == "" {
+		orKey = os.Getenv("OPENROUTER_API_KEY")
+	}
 	cpKey := os.Getenv("HEXAI_COPILOT_API_KEY")
 	if strings.TrimSpace(cpKey) == "" {
 		cpKey = os.Getenv("COPILOT_API_KEY")
 	}
-	return llm.NewFromConfig(llmCfg, oaKey, cpKey)
+	return llm.NewFromConfig(llmCfg, oaKey, orKey, cpKey)
 }
diff --git a/internal/lsp/server.go b/internal/lsp/server.go
index 8e210b4..d55a967 100644
--- a/internal/lsp/server.go
+++ b/internal/lsp/server.go
@@ -217,26 +217,33 @@ func (s *Server) currentLLMClient() llm.Client {
 
 func newClientForProvider(cfg appconfig.App, provider string) (llm.Client, error) {
 	llmCfg := llm.Config{
-		Provider:           provider,
-		OpenAIBaseURL:      cfg.OpenAIBaseURL,
-		OpenAIModel:        cfg.OpenAIModel,
-		OpenAITemperature:  cfg.OpenAITemperature,
-		OllamaBaseURL:      cfg.OllamaBaseURL,
-		OllamaModel:        cfg.OllamaModel,
-		OllamaTemperature:  cfg.OllamaTemperature,
-		CopilotBaseURL:     cfg.CopilotBaseURL,
-		CopilotModel:       cfg.CopilotModel,
-		CopilotTemperature: cfg.CopilotTemperature,
+		Provider:              provider,
+		OpenAIBaseURL:         cfg.OpenAIBaseURL,
+		OpenAIModel:           cfg.OpenAIModel,
+		OpenAITemperature:     cfg.OpenAITemperature,
+		OpenRouterBaseURL:     cfg.OpenRouterBaseURL,
+		OpenRouterModel:       cfg.OpenRouterModel,
+		OpenRouterTemperature: cfg.OpenRouterTemperature,
+		OllamaBaseURL:         cfg.OllamaBaseURL,
+		OllamaModel:           cfg.OllamaModel,
+		OllamaTemperature:     cfg.OllamaTemperature,
+		CopilotBaseURL:        cfg.CopilotBaseURL,
+		CopilotModel:          cfg.CopilotModel,
+		CopilotTemperature:    cfg.CopilotTemperature,
 	}
 	oaKey := strings.TrimSpace(os.Getenv("HEXAI_OPENAI_API_KEY"))
 	if oaKey == "" {
 		oaKey = strings.TrimSpace(os.Getenv("OPENAI_API_KEY"))
 	}
+	orKey := strings.TrimSpace(os.Getenv("HEXAI_OPENROUTER_API_KEY"))
+	if orKey == "" {
+		orKey = strings.TrimSpace(os.Getenv("OPENROUTER_API_KEY"))
+	}
 	cpKey := strings.TrimSpace(os.Getenv("HEXAI_COPILOT_API_KEY"))
 	if cpKey == "" {
 		cpKey = strings.TrimSpace(os.Getenv("COPILOT_API_KEY"))
 	}
-	return llm.NewFromConfig(llmCfg, oaKey, cpKey)
+	return llm.NewFromConfig(llmCfg, oaKey, orKey, cpKey)
 }
 
 func (s *Server) clientFor(spec requestSpec) llm.Client {
@@ -273,6 +280,12 @@ func (s *Server) clientFor(spec requestSpec) llm.Client {
 		} else if spec.fallbackModel != "" {
 			cfg.OpenAIModel = spec.fallbackModel
 		}
+	case "openrouter":
+		if modelOverride != "" {
+			cfg.OpenRouterModel = modelOverride
+		} else if spec.fallbackModel != "" {
+			cfg.OpenRouterModel = spec.fallbackModel
+		}
 	case "copilot":
 		if modelOverride != "" {
 			cfg.CopilotModel = modelOverride
diff --git a/internal/lsp/server_test.go b/internal/lsp/server_test.go
index 4f24b57..836e43f 100644
--- a/internal/lsp/server_test.go
+++ b/internal/lsp/server_test.go
@@ -85,3 +85,20 @@ func TestServerApplyOptions(t *testing.T) {
 		t.Fatalf("expected config to update, got %d", got)
 	}
 }
+
+func TestServerStoreAndTakePendingCompletion(t *testing.T) {
+	s := newTestServer()
+	items := []CompletionItem{{Label: "foo"}}
+	s.storePendingCompletion("key", items)
+	if len(s.pendingCompletions) != 1 {
+		t.Fatalf("expected pending map to be populated")
+	}
+	items[0].Label = "bar" // ensure copy stored
+	got := s.takePendingCompletion("key")
+	if len(got) != 1 || got[0].Label != "foo" {
+		t.Fatalf("expected preserved copy of completion, got %+v", got)
+	}
+	if len(s.pendingCompletions) != 0 {
+		t.Fatalf("expected pending map to be cleared after take")
+	}
+}
diff --git a/internal/version.go b/internal/version.go
index f781c7a..a28ebba 100644
--- a/internal/version.go
+++ b/internal/version.go
@@ -1,4 +1,4 @@
 // Summary: Hexai semantic version identifier used by CLI and LSP binaries.
 package internal
 
-const Version = "0.14.0"
+const Version = "0.15.0"