execute, agent: thread workdir through Decl and AgentCoreConfig

execute.Decl is now a function (func(workdir string) func() tools.Server)
rather than a var, making workdir an explicit dependency rather than
an implicit os.Getwd() call. execute.Server stores the workdir and
sets cmd.Dir accordingly; falls back to os.Getwd() if empty.

AgentCoreConfig gains WorkDir string, threaded into BuildAgentEnv and
the system prompt. The /agent switch uses s.workdir so the correct
directory is preserved across agent switches.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pkg/agent/core.go

@@ -119,14 +119,16 @@ func buildFirstPrompt(input string) string {
 }
 
 // systemPrompt builds the full system prompt for a given tool set.
-func systemPrompt(allTools []backend.Tool) string {
-	cwd, _ := os.Getwd()
+func systemPrompt(allTools []backend.Tool, workdir string) string {
+	if workdir == "" {
+		workdir, _ = os.Getwd()
+	}
 	now := time.Now().Format("2006-01-02 15:04:05 MST")
 	names := make([]string, len(allTools))
 	for i, t := range allTools {
 		names[i] = t.Name
 	}
-	return systemPromptBase + "\n\nWorking directory: " + cwd +
+	return systemPromptBase + "\n\nWorking directory: " + workdir +
 		"\nCurrent time: " + now +
 		"\nAvailable tools: " + strings.Join(names, ", ")
 }
@@ -144,9 +146,10 @@ type AgentEnv struct {
 }
 
 // BuildAgentEnv constructs an AgentEnv from a pre-configured Dispatcher and
-// optional agent config. The caller is responsible for registering all servers
-// on d before calling this.
-func BuildAgentEnv(cfg *config.Config, d tools.Dispatcher) AgentEnv {
+// optional agent config. workdir sets the working directory reported in the
+// system prompt; if empty, the process working directory is used.
+// The caller is responsible for registering all servers on d before calling this.
+func BuildAgentEnv(cfg *config.Config, d tools.Dispatcher, workdir string) AgentEnv {
 	var messages []string
 
 	if cfg != nil {
@@ -193,9 +196,9 @@ func BuildAgentEnv(cfg *config.Config, d tools.Dispatcher) AgentEnv {
 		}
 	}
 
-	sp := systemPrompt(allTools)
+	sp := systemPrompt(allTools, workdir)
 	if agentPrompt != "" {
-		sp = systemPrompt(allTools) + "\n\n" + agentPrompt
+		sp = systemPrompt(allTools, workdir) + "\n\n" + agentPrompt
 	}
 
 	overhead := len(sp)
@@ -281,6 +284,7 @@ type AgentCoreConfig struct {
 	AgentsDir   string
 	SessionsDir string
 	SessionID   string
+	WorkDir     string // working directory for tool execution and system prompt
 	Session     *Session
 	Env           AgentEnv
 	NewDispatcher func() tools.Dispatcher
@@ -298,6 +302,7 @@ type agentCore struct {
 	sessionID     string
 	dispatcher    tools.Dispatcher
 	newDispatcher func() tools.Dispatcher
+	workdir       string
 	ctxOverhead   int
 	currentAction atomic.Pointer[actionHandle]
 }
@@ -325,6 +330,7 @@ func NewAgentCore(cfg AgentCoreConfig) Core {
 		agentsDir:     cfg.AgentsDir,
 		sessionsDir:   cfg.SessionsDir,
 		sessionID:     cfg.SessionID,
+		workdir:       cfg.WorkDir,
 		dispatcher:    cfg.Env.dispatcher,
 		newDispatcher: cfg.NewDispatcher,
 		ctxOverhead:   cfg.Env.CtxOverhead,
@@ -500,7 +506,7 @@ func (s *agentCore) handleCommand(ctx context.Context, input string, handler Eve
 			s.dispatcher.Close()
 		}
 		d := s.newDispatcher()
-		env := BuildAgentEnv(cfg, d)
+		env := BuildAgentEnv(cfg, d, s.workdir)
 		s.dispatcher = env.dispatcher
 		s.hooks = env.Hooks
 		s.loopcfg.systemPrompt = env.systemPrompt

pkg/tools/execute/executor.go

@@ -24,6 +24,10 @@ type Server struct {
 	// If it returns false, the operation is denied.
 	Confirm func(string) bool
 
+	// workdir is the working directory for sandboxed commands. If empty,
+	// the process working directory is used.
+	workdir string
+
 	// rate limiting state (per-Server)
 	rateLimitMu        sync.Mutex
 	validationFailures int
@@ -31,8 +35,8 @@ type Server struct {
 	blockedUntil       time.Time
 }
 
-// New creates a new Server.
-func New() *Server { return &Server{} }
+// New creates a new Server with the given working directory.
+func New(workdir string) *Server { return &Server{workdir: workdir} }
 
 var dangerousPatterns = []*regexp.Regexp{
 	regexp.MustCompile(`rm\s+(-[a-z]*r[a-z]*\s+)*-[a-z]*f[a-z]*\s*/(home|var|usr|etc|boot|root|bin|sbin|lib|opt|srv)?`),
@@ -158,7 +162,10 @@ func (e *Server) Execute(ctx context.Context, code, language string, timeout int
 		return "", err
 	}
 
-	workDir, _ := os.Getwd()
+	workDir := e.workdir
+	if workDir == "" {
+		workDir, _ = os.Getwd()
+	}
 
 	ctx, cancel := context.WithTimeout(ctx, time.Duration(timeout)*time.Second)
 	defer cancel()

pkg/tools/execute/server.go

@@ -7,8 +7,10 @@ import (
 	"ollie/pkg/tools"
 )
 
-// Decl is the default factory for an execute Server. Reassign to override.
-var Decl func() tools.Server = func() tools.Server { return New() }
+// Decl returns a factory for an execute Server with the given working directory.
+func Decl(workdir string) func() tools.Server {
+	return func() tools.Server { return New(workdir) }
+}
 
 // ListTools implements tools.Server.
 func (e *Server) ListTools() ([]tools.ToolInfo, error) {