+// Agent is one agent and its directory. The directory holds config.json, the
+// user's instructions in instructions.md, the chat, and the usage file.
+type Agent struct {
+ dir string
+ config AgentConfig
+}
+
+// CacheKey returns the prompt cache key of every model call of the agent.
+func (a *Agent) CacheKey() string {
+ return "onechat-" + a.config.ID
+}
+
+// Prompt returns the system prompt of the agent with the user's instructions
+// from instructions.md. It reads the file on each call, so a change applies at
+// the next call. A missing file means no instructions.
+func (a *Agent) Prompt() (string, error) {
+ instructions, err := a.instructions()
+ if err != nil {
+ return "", fmt.Errorf("read prompt instructions: %w", err)
+ }
+
+ path, err := filepath.Abs(filepath.Join(a.dir, agentInstructionsFileName))
+ if err != nil {
+ return "", fmt.Errorf("find instructions path: %w", err)
+ }
+
+ if a.config.Parent != "" {
+ return promptChild(a.config.Name, a.config.Parent, a.config.Responsibility, path, instructions), nil
+ }
+
+ return prompt(a.config.Name, path, instructions), nil
+}
+
+// Tools returns the tools shared by the turns and compactions of this agent. A
+// child has no WhatsApp tools.
+func (a *Agent) Tools() []ModelTool {
+ tools := promptTools()
+ if a.config.Parent != "" {
+ tools = slices.DeleteFunc(tools, func(tool ModelTool) bool {
+ return strings.HasPrefix(tool.Name, "whatsapp_")
+ })
+ }
+
+ return tools
+}
+
+// Children reads the direct children in directory order. Each child needs an
+// existing config with its directory name and this agent as parent. Children
+// cannot have children. A missing children directory means no children.
+func (a *Agent) Children() ([]*Agent, error) {
+ dir := filepath.Join(a.dir, "children")
+ entries, err := os.ReadDir(dir)
+ if errors.Is(err, os.ErrNotExist) {
+ return nil, nil
+ }
+
+ if err != nil {
+ return nil, fmt.Errorf("read children: %w", err)
+ }
+
+ if a.config.Parent != "" && len(entries) != 0 {
+ return nil, errors.New("children cannot have children")
+ }
+
+ var children []*Agent
+
+ keys := map[string]bool{a.CacheKey(): true}
+
+ for _, entry := range entries {
+ name := entry.Name()
+ if !entry.IsDir() {
+ return nil, fmt.Errorf("child %q must be a directory", name)
+ }
+
+ path := filepath.Join(dir, name)
+ _, err = os.Stat(filepath.Join(path, "config.json"))
+ if err != nil {
+ return nil, fmt.Errorf("child %q config: %w", name, err)
+ }
+
+ child, err := openAgent(path)
+ if err != nil {
+ return nil, fmt.Errorf("open child %q: %w", name, err)
+ }
+
+ if child.config.Name != name || child.config.Parent != a.config.Name {
+ return nil, fmt.Errorf("child %q needs name %q and parent %q", name, name, a.config.Name)
+ }
+
+ if child.config.Name == a.config.Name || keys[child.CacheKey()] {
+ return nil, fmt.Errorf("child %q must have its own name and ID", name)
+ }
+
+ keys[child.CacheKey()] = true
+ _, err = child.Children()
+ if err != nil {
+ return nil, fmt.Errorf("read child %q: %w", name, err)
+ }
+
+ children = append(children, child)
+ }
+
+ return children, nil
+}
+
+// SubagentPrompt returns the system prompt of a subagent of the agent, with the
+// user's instructions as Prompt reads them.
+func (a *Agent) SubagentPrompt() (string, error) {
+ instructions, err := a.instructions()
+ if err != nil {
+ return "", err
+ }
+
+ return promptSubagent(a.config.Name, instructions), nil
+}
+
+// instructions reads the user's instructions from instructions.md. A missing
+// file means no instructions.
+func (a *Agent) instructions() (string, error) {
+ data, err := os.ReadFile(filepath.Join(a.dir, agentInstructionsFileName))
+ if err != nil && !errors.Is(err, os.ErrNotExist) {
+ return "", fmt.Errorf("read instructions: %w", err)
+ }
+
+ return string(data), nil
+}
+
+// AgentConfig holds the settings of the config.json of an agent. ID is random,
+// made once when the file is made, and never changes. The cache key comes from
+// the ID, so a rename keeps the prompt cache and two agents with one name do
+// not share a key. Workdir is the directory where the commands of the agent
+// run. Responsibility and Parent are set together for a child agent.
+type AgentConfig struct {
+ Name string `json:"name"`
+ ID string `json:"id"`
+ Model string `json:"model"`
+ Effort string `json:"effort"`
+ Workdir string `json:"workdir"`
+ Responsibility string `json:"responsibility,omitempty"`
+ Parent string `json:"parent,omitempty"`
+}
+
+// validate makes sure that each setting has a valid value.
+func (c AgentConfig) validate() error {
+ if c.Name == "" || strings.ContainsAny(c.Name, "\r\n") {
+ return errors.New("name must be one line of text")
+ }
+
+ id, err := hex.DecodeString(c.ID)
+ if err != nil || len(id) != agentIDBytes {
+ return fmt.Errorf("id must be %d hexadecimal digits", 2*agentIDBytes)
+ }
+
+ if c.Model == "" || c.Effort == "" {
+ return errors.New("agent needs a model and an effort")
+ }
+
+ if (strings.TrimSpace(c.Responsibility) == "") != (c.Parent == "") {
+ return errors.New("a child needs both responsibility and parent")
+ }
+
+ if strings.ContainsAny(c.Parent, "\r\n") {
+ return errors.New("parent must be one line of text")
+ }
+
+ if !filepath.IsAbs(c.Workdir) {
+ return fmt.Errorf("workdir %q is not an absolute path", c.Workdir)
+ }
+
+ return nil
+}
+
projects / onechat / blobdiff