refactor: cleanup dead code and turn on dead code detection in CI (#515)

* cleanup dead code.

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

* add these two back with flag.

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

* fix ci

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

* remove this confusing line

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

* make fmt

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

* remove unused method.

picked up by golangci-lint run

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

---------

Signed-off-by: Kai Xia <kaix+github@fastmail.com>

.golangci.yaml

@@ -66,7 +66,6 @@ linters:
     - testifylint
     - thelper
     - unparam
-    - unused
     - usestdlibvars
     - usetesting
     - wastedassign
@@ -152,6 +151,9 @@ linters:
           - gocognit
           - gocyclo
         path: _test\.go$
+      - linters:
+          - nolintlint
+        path: 'pkg/tools/(i2c\.go|spi\.go)$'
 
 issues:
   max-issues-per-linter: 0

pkg/agent/context.go

@@ -288,25 +288,6 @@ func (cb *ContextBuilder) AddAssistantMessage(
 	return messages
 }
 
-func (cb *ContextBuilder) loadSkills() string {
-	allSkills := cb.skillsLoader.ListSkills()
-	if len(allSkills) == 0 {
-		return ""
-	}
-
-	var skillNames []string
-	for _, s := range allSkills {
-		skillNames = append(skillNames, s.Name)
-	}
-
-	content := cb.skillsLoader.LoadSkillsForContext(skillNames)
-	if content == "" {
-		return ""
-	}
-
-	return "# Skill Definitions\n\n" + content
-}
-
 // GetSkillsInfo returns information about loaded skills.
 func (cb *ContextBuilder) GetSkillsInfo() map[string]any {
 	allSkills := cb.skillsLoader.ListSkills()

pkg/channels/wecom_app.go

@@ -571,61 +571,6 @@ func (c *WeComAppChannel) sendTextMessage(ctx context.Context, accessToken, user
 	return nil
 }
 
-// sendMarkdownMessage sends a markdown message to a user
-func (c *WeComAppChannel) sendMarkdownMessage(ctx context.Context, accessToken, userID, content string) error {
-	apiURL := fmt.Sprintf("%s/cgi-bin/message/send?access_token=%s", wecomAPIBase, accessToken)
-
-	msg := WeComMarkdownMessage{
-		ToUser:  userID,
-		MsgType: "markdown",
-		AgentID: c.config.AgentID,
-	}
-	msg.Markdown.Content = content
-
-	jsonData, err := json.Marshal(msg)
-	if err != nil {
-		return fmt.Errorf("failed to marshal message: %w", err)
-	}
-
-	// Use configurable timeout (default 5 seconds)
-	timeout := c.config.ReplyTimeout
-	if timeout <= 0 {
-		timeout = 5
-	}
-
-	reqCtx, cancel := context.WithTimeout(ctx, time.Duration(timeout)*time.Second)
-	defer cancel()
-
-	req, err := http.NewRequestWithContext(reqCtx, http.MethodPost, apiURL, bytes.NewBuffer(jsonData))
-	if err != nil {
-		return fmt.Errorf("failed to create request: %w", err)
-	}
-	req.Header.Set("Content-Type", "application/json")
-
-	client := &http.Client{Timeout: time.Duration(timeout) * time.Second}
-	resp, err := client.Do(req)
-	if err != nil {
-		return fmt.Errorf("failed to send message: %w", err)
-	}
-	defer resp.Body.Close()
-
-	body, err := io.ReadAll(resp.Body)
-	if err != nil {
-		return fmt.Errorf("failed to read response: %w", err)
-	}
-
-	var sendResp WeComSendMessageResponse
-	if err := json.Unmarshal(body, &sendResp); err != nil {
-		return fmt.Errorf("failed to parse response: %w", err)
-	}
-
-	if sendResp.ErrCode != 0 {
-		return fmt.Errorf("API error: %s (code: %d)", sendResp.ErrMsg, sendResp.ErrCode)
-	}
-
-	return nil
-}
-
 // handleHealth handles health check requests
 func (c *WeComAppChannel) handleHealth(w http.ResponseWriter, r *http.Request) {
 	status := map[string]any{

pkg/devices/sources/usb_linux.go

@@ -36,7 +36,6 @@ var usbClassToCapability = map[string]string{
 
 type USBMonitor struct {
 	cmd *exec.Cmd
-	cancel context.CancelFunc
 	mu  sync.Mutex
 }
 

pkg/providers/antigravity_provider.go

@@ -404,64 +404,6 @@ type antigravityJSONResponse struct {
 	} `json:"usageMetadata"`
 }
 
-func (p *AntigravityProvider) parseJSONResponse(body []byte) (*LLMResponse, error) {
-	var resp antigravityJSONResponse
-	if err := json.Unmarshal(body, &resp); err != nil {
-		return nil, fmt.Errorf("parsing antigravity response: %w", err)
-	}
-
-	if len(resp.Candidates) == 0 {
-		return nil, fmt.Errorf("antigravity: no candidates in response")
-	}
-
-	candidate := resp.Candidates[0]
-	var contentParts []string
-	var toolCalls []ToolCall
-
-	for _, part := range candidate.Content.Parts {
-		if part.Text != "" {
-			contentParts = append(contentParts, part.Text)
-		}
-		if part.FunctionCall != nil {
-			argumentsJSON, _ := json.Marshal(part.FunctionCall.Args)
-			toolCalls = append(toolCalls, ToolCall{
-				ID:        fmt.Sprintf("call_%s_%d", part.FunctionCall.Name, time.Now().UnixNano()),
-				Name:      part.FunctionCall.Name,
-				Arguments: part.FunctionCall.Args,
-				Function: &FunctionCall{
-					Name:             part.FunctionCall.Name,
-					Arguments:        string(argumentsJSON),
-					ThoughtSignature: extractPartThoughtSignature(part.ThoughtSignature, part.ThoughtSignatureSnake),
-				},
-			})
-		}
-	}
-
-	finishReason := "stop"
-	if len(toolCalls) > 0 {
-		finishReason = "tool_calls"
-	}
-	if candidate.FinishReason == "MAX_TOKENS" {
-		finishReason = "length"
-	}
-
-	var usage *UsageInfo
-	if resp.UsageMetadata.TotalTokenCount > 0 {
-		usage = &UsageInfo{
-			PromptTokens:     resp.UsageMetadata.PromptTokenCount,
-			CompletionTokens: resp.UsageMetadata.CandidatesTokenCount,
-			TotalTokens:      resp.UsageMetadata.TotalTokenCount,
-		}
-	}
-
-	return &LLMResponse{
-		Content:      strings.Join(contentParts, ""),
-		ToolCalls:    toolCalls,
-		FinishReason: finishReason,
-		Usage:        usage,
-	}, nil
-}
-
 func (p *AntigravityProvider) parseSSEResponse(body string) (*LLMResponse, error) {
 	var contentParts []string
 	var toolCalls []ToolCall

pkg/providers/fallback_test.go

@@ -17,12 +17,6 @@ func successRun(content string) func(ctx context.Context, provider, model string
 	}
 }
 
-func failRun(err error) func(ctx context.Context, provider, model string) (*LLMResponse, error) {
-	return func(ctx context.Context, provider, model string) (*LLMResponse, error) {
-		return nil, err
-	}
-}
-
 func TestFallback_SingleCandidate_Success(t *testing.T) {
 	ct := NewCooldownTracker()
 	fc := NewFallbackChain(ct)

pkg/tools/i2c.go

@@ -117,13 +117,19 @@ func (t *I2CTool) detect() *ToolResult {
 	return SilentResult(fmt.Sprintf("Found %d I2C bus(es):\n%s", len(buses), string(result)))
 }
 
+// Helper functions for I2C operations (used by platform-specific implementations)
+
 // isValidBusID checks that a bus identifier is a simple number (prevents path injection)
+//
+//nolint:unused // Used by i2c_linux.go
 func isValidBusID(id string) bool {
 	matched, _ := regexp.MatchString(`^\d+$`, id)
 	return matched
 }
 
 // parseI2CAddress extracts and validates an I2C address from args
+//
+//nolint:unused // Used by i2c_linux.go
 func parseI2CAddress(args map[string]any) (int, *ToolResult) {
 	addrFloat, ok := args["address"].(float64)
 	if !ok {
@@ -137,6 +143,8 @@ func parseI2CAddress(args map[string]any) (int, *ToolResult) {
 }
 
 // parseI2CBus extracts and validates an I2C bus from args
+//
+//nolint:unused // Used by i2c_linux.go
 func parseI2CBus(args map[string]any) (string, *ToolResult) {
 	bus, ok := args["bus"].(string)
 	if !ok || bus == "" {

pkg/tools/spi.go

@@ -119,7 +119,11 @@ func (t *SPITool) list() *ToolResult {
 	return SilentResult(fmt.Sprintf("Found %d SPI device(s):\n%s", len(devices), string(result)))
 }
 
+// Helper function for SPI operations (used by platform-specific implementations)
+
 // parseSPIArgs extracts and validates common SPI parameters
+//
+//nolint:unused // Used by spi_linux.go
 func parseSPIArgs(args map[string]any) (device string, speed uint32, mode uint8, bits uint8, errMsg string) {
 	dev, ok := args["device"].(string)
 	if !ok || dev == "" {