Add Skills System

cmd/shelley/main.go

@@ -95,8 +95,9 @@ func runServe(global GlobalConfig, args []string) {
 	database := setupDatabase(global.DBPath, logger)
 	defer database.Close()
 
-	// Set the database path for system prompt generation
+	// Set the database path and port for system prompt generation
 	server.DBPath = global.DBPath
+	server.Port = *port
 
 	// Build LLM configuration
 	llmConfig := buildLLMConfig(logger, global.ConfigPath, global.TerminalURL, global.DefaultModel)

loop/loop.go

@@ -82,6 +82,16 @@ func NewLoop(config Config) *Loop {
 	}
 }
 
+// SetSystem sets the system prompt for the loop.
+// This should be called before processing any messages if the system
+// prompt wasn't available at loop creation time.
+func (l *Loop) SetSystem(system []llm.SystemContent) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	l.system = system
+	l.logger.Debug("set system prompt", "system_items", len(system))
+}
+
 // QueueUserMessage adds a user message to the queue to be processed
 func (l *Loop) QueueUserMessage(message llm.Message) {
 	l.mu.Lock()

server/convo.go

@@ -40,6 +40,7 @@ type ConversationManager struct {
 
 	hydrated              bool
 	hasConversationEvents bool
+	needsSystemPrompt     bool
 	cwd                   string // working directory for tools
 }
 
@@ -87,15 +88,7 @@ func (cm *ConversationManager) Hydrate(ctx context.Context) error {
 		return fmt.Errorf("failed to get conversation history: %w", err)
 	}
 
-	if conversation.UserInitiated && !hasSystemMessage(messages) {
-		systemMsg, err := cm.createSystemPrompt(ctx)
-		if err != nil {
-			return err
-		}
-		if systemMsg != nil {
-			messages = append(messages, *systemMsg)
-		}
-	}
+	cm.needsSystemPrompt = conversation.UserInitiated && !hasSystemMessage(messages)
 
 	history, system := cm.partitionMessages(messages)
 
@@ -135,6 +128,17 @@ func (cm *ConversationManager) AcceptUserMessage(ctx context.Context, service ll
 		return false, err
 	}
 
+	// Create system prompt now that we know the model
+	cm.mu.Lock()
+	needsSystemPrompt := cm.needsSystemPrompt
+	cm.needsSystemPrompt = false
+	cm.mu.Unlock()
+	if needsSystemPrompt {
+		if _, err := cm.createSystemPrompt(ctx); err != nil {
+			return false, fmt.Errorf("failed to create system prompt: %w", err)
+		}
+	}
+
 	cm.mu.Lock()
 	isFirst := !cm.hasConversationEvents
 	cm.hasConversationEvents = true
@@ -178,7 +182,7 @@ func hasSystemMessage(messages []generated.Message) bool {
 }
 
 func (cm *ConversationManager) createSystemPrompt(ctx context.Context) (*generated.Message, error) {
-	systemPrompt, err := GenerateSystemPrompt(cm.cwd)
+	systemPrompt, err := GenerateSystemPrompt(cm.cwd, cm.modelID)
 	if err != nil {
 		return nil, fmt.Errorf("failed to generate system prompt: %w", err)
 	}
@@ -209,6 +213,14 @@ func (cm *ConversationManager) createSystemPrompt(ctx context.Context) (*generat
 		cm.logger.Warn("Failed to update conversation timestamp after system prompt", "error", err)
 	}
 
+	// Update the loop's system prompt if it's already running
+	cm.mu.Lock()
+	loopInstance := cm.loop
+	cm.mu.Unlock()
+	if loopInstance != nil {
+		loopInstance.SetSystem([]llm.SystemContent{{Type: "text", Text: systemPrompt}})
+	}
+
 	cm.logger.Info("Stored system prompt", "length", len(systemPrompt))
 	return created, nil
 }

server/skill_test.go

@@ -0,0 +1,76 @@
+package server
+
+import "testing"
+
+func TestParseSkillPreamble(t *testing.T) {
+	tests := []struct {
+		name     string
+		content  string
+		expected string
+	}{
+		{
+			name: "name and inline description",
+			content: `---
+name: test-skill
+description: A simple test skill
+---
+# Test Skill
+`,
+			expected: "test-skill: A simple test skill",
+		},
+		{
+			name: "multiline description with >",
+			content: `---
+name: pdf-processor
+description: >
+  Process PDF files including extraction,
+  form filling, and merging.
+---
+# PDF Processor
+`,
+			expected: "pdf-processor: Process PDF files including extraction, form filling, and merging.",
+		},
+		{
+			name: "multiline description with |",
+			content: `---
+name: code-reviewer
+description: |
+  Reviews code for quality.
+  Checks for common issues.
+---
+`,
+			expected: "code-reviewer: Reviews code for quality. Checks for common issues.",
+		},
+		{
+			name: "name only",
+			content: `---
+name: minimal-skill
+---
+# Minimal
+`,
+			expected: "minimal-skill",
+		},
+		{
+			name: "no name",
+			content: `---
+description: A skill without a name
+---
+`,
+			expected: "",
+		},
+		{
+			name:     "no frontmatter",
+			content:  "# Just a markdown file\n",
+			expected: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := parseSkillPreamble(tt.content)
+			if got != tt.expected {
+				t.Errorf("parseSkillPreamble() = %q, want %q", got, tt.expected)
+			}
+		})
+	}
+}

server/system_prompt.go

@@ -22,11 +22,17 @@ type SystemPromptData struct {
 	IsSudoAvailable  bool
 	Hostname         string // For exe.dev, the public hostname (e.g., "vmname.exe.xyz")
 	ShelleyDBPath    string // Path to the shelley database
+	ShelleyPort      string // Port Shelley is running on
+	ShelleyBaseURL   string // Full base URL for Shelley web UI
+	ModelName        string // LLM model being used for this conversation
 }
 
 // DBPath is the path to the shelley database, set at startup
 var DBPath string
 
+// Port is the port Shelley is running on, set at startup
+var Port string
+
 type GitInfo struct {
 	Root string
 }
@@ -35,15 +41,17 @@ type CodebaseInfo struct {
 	InjectFiles        []string
 	InjectFileContents map[string]string
 	GuidanceFiles      []string
+	SkillPreambles     []string // Preambles from installed skills
 }
 
 // GenerateSystemPrompt generates the system prompt using the embedded template.
 // If workingDir is empty, it uses the current working directory.
-func GenerateSystemPrompt(workingDir string) (string, error) {
+func GenerateSystemPrompt(workingDir string, modelName string) (string, error) {
 	data, err := collectSystemData(workingDir)
 	if err != nil {
 		return "", fmt.Errorf("failed to collect system data: %w", err)
 	}
+	data.ModelName = modelName
 
 	tmpl, err := template.New("system_prompt").Parse(systemPromptTemplate)
 	if err != nil {
@@ -102,6 +110,25 @@ func collectSystemData(workingDir string) (*SystemPromptData, error) {
 		}
 	}
 
+	// Set Shelley port and base URL
+	if Port != "" {
+		data.ShelleyPort = Port
+		if data.IsExeDev {
+			if Port == "9999" {
+				// Default port uses shelley.exe.xyz subdomain
+				if hostname, err := os.Hostname(); err == nil {
+					data.ShelleyBaseURL = "https://" + hostname + ".shelley.exe.xyz"
+				}
+			} else {
+				// Other ports use hostname:port
+				data.ShelleyBaseURL = "https://" + data.Hostname + ":" + Port
+			}
+		} else {
+			// Not exe.dev - use localhost
+			data.ShelleyBaseURL = "http://localhost:" + Port
+		}
+	}
+
 	// Set shelley database path if it was configured
 	if DBPath != "" {
 		// Convert to absolute path if relative
@@ -162,6 +189,9 @@ func collectCodebaseInfo(wd string, gitInfo *GitInfo) (*CodebaseInfo, error) {
 				seenFiles[lowerPath] = true
 			}
 		}
+
+		// Load installed skills from ~/.config/shelley/skills/
+		info.SkillPreambles = loadSkillPreambles(home)
 	}
 
 	// Determine the root directory to search
@@ -287,3 +317,82 @@ func isSudoAvailable() bool {
 	_, err := cmd.CombinedOutput()
 	return err == nil
 }
+
+// loadSkillPreambles reads SKILL.md files from ~/.config/shelley/skills/ (following
+// Anthropic's skill format) and extracts name + description from YAML frontmatter.
+func loadSkillPreambles(home string) []string {
+	skillsDir := filepath.Join(home, ".config", "shelley", "skills")
+	entries, err := os.ReadDir(skillsDir)
+	if err != nil {
+		return nil
+	}
+
+	var preambles []string
+	for _, entry := range entries {
+		if !entry.IsDir() {
+			continue
+		}
+		skillFile := filepath.Join(skillsDir, entry.Name(), "SKILL.md")
+		content, err := os.ReadFile(skillFile)
+		if err != nil {
+			continue
+		}
+		if preamble := parseSkillPreamble(string(content)); preamble != "" {
+			preambles = append(preambles, preamble)
+		}
+	}
+	return preambles
+}
+
+// parseSkillPreamble extracts name and description from YAML frontmatter,
+// following Anthropic's skill format (https://docs.anthropic.com/en/docs/claude-code/skills).
+// Returns "name: description" for injection into the system prompt.
+func parseSkillPreamble(content string) string {
+	if !strings.HasPrefix(content, "---") {
+		return ""
+	}
+	// Find the closing ---
+	endIdx := strings.Index(content[3:], "\n---")
+	if endIdx == -1 {
+		return ""
+	}
+	frontmatter := content[4 : endIdx+3] // Skip initial ---\n
+
+	// Extract name and description fields
+	var name, description string
+	lines := strings.Split(frontmatter, "\n")
+	for i, line := range lines {
+		trimmed := strings.TrimSpace(line)
+		if strings.HasPrefix(trimmed, "name:") {
+			name = strings.TrimSpace(strings.TrimPrefix(trimmed, "name:"))
+		} else if strings.HasPrefix(trimmed, "description:") {
+			// Check if it's inline or multiline (> or |)
+			value := strings.TrimSpace(strings.TrimPrefix(trimmed, "description:"))
+			if value != "" && value != "|" && value != ">" {
+				description = value
+			} else {
+				// Multiline: collect indented lines
+				var multiline []string
+				for j := i + 1; j < len(lines); j++ {
+					if len(lines[j]) == 0 {
+						continue
+					}
+					if lines[j][0] == ' ' || lines[j][0] == '\t' {
+						multiline = append(multiline, strings.TrimSpace(lines[j]))
+					} else {
+						break
+					}
+				}
+				description = strings.Join(multiline, " ")
+			}
+		}
+	}
+
+	if name == "" {
+		return ""
+	}
+	if description == "" {
+		return name
+	}
+	return name + ": " + description
+}

server/system_prompt.txt

@@ -3,6 +3,9 @@ You are Shelley, a coding agent and assistant. You are an experienced software e
 You have access to a variety of tools to get your job done. Be persistent and creative.
 
 Working directory: {{.WorkingDirectory}}
+{{if .ModelName}}
+Model: {{.ModelName}}
+{{end}}
 
 {{if .GitInfo}}
 Git repository root: {{.GitInfo.Root}}
@@ -62,6 +65,25 @@ Direct user instructions from the current conversation always take highest prece
 {{end}}</directory_specific_guidance_files>
 {{end}}
 {{end}}
+<skills>
+Skills extend Shelley with additional capabilities, following Anthropic's skill format.
+Skills are installed in ~/.config/shelley/skills/<name>/SKILL.md.
+
+To install a skill from a URL: curl -sL <url> -o /tmp/s.zip && n=$(unzip -p /tmp/s.zip SKILL.md | grep '^name:' | cut -d: -f2 | tr -d ' ') && mkdir -p ~/.config/shelley/skills/$n && unzip -o /tmp/s.zip -d ~/.config/shelley/skills/$n
+{{if .Codebase.SkillPreambles}}
+Installed skills:
+{{range .Codebase.SkillPreambles}}- {{.}}
+{{end}}{{else}}No skills currently installed.
+{{end}}
+To check for newly installed skills or get full details, read ~/.config/shelley/skills/ and each skill's SKILL.md.
+</skills>
+{{if .ShelleyBaseURL}}
+<shelley_web_ui>
+Shelley web UI: {{.ShelleyBaseURL}}
+To link to a conversation: {{.ShelleyBaseURL}}/c/<slug>
+To link to this conversation, use the slug from the current URL or query the database.
+</shelley_web_ui>
+{{end}}
 {{if .ShelleyDBPath}}
 <previous_conversations>
 Your conversation history is stored in a SQLite database at: {{.ShelleyDBPath}}