diff --git a/dify-agent-runtime/Makefile b/dify-agent-runtime/Makefile
index 64550ef16ce..40cf168c18a 100644
--- a/dify-agent-runtime/Makefile
+++ b/dify-agent-runtime/Makefile
@@ -4,7 +4,7 @@ PROTO_SRC := ../dify-agent/proto/dify/agent/stub/v1/agent_stub.proto
 PROTO_OUT := gen
 AGENT_CLI_HELP_JSON := ../dify-agent/src/dify_agent/layers/_agent_cli_help.json
 
-build: $(BIN_DIR)/shellctl $(BIN_DIR)/shellctl-sanitize-pty $(BIN_DIR)/shellctl-runner-exit $(BIN_DIR)/dify-agent gen-cli-help
+build: $(BIN_DIR)/shellctl $(BIN_DIR)/shellctl-sanitize-pty $(BIN_DIR)/shellctl-runner-exit $(BIN_DIR)/shellctl-runner $(BIN_DIR)/dify-agent gen-cli-help
 
 $(BIN_DIR)/shellctl: $(shell find cmd/shellctl internal -name '*.go')
 	go build -o $@ ./cmd/shellctl
@@ -15,6 +15,10 @@ $(BIN_DIR)/shellctl-sanitize-pty: $(shell find cmd/sanitize-pty internal/sanitiz
 $(BIN_DIR)/shellctl-runner-exit: $(shell find cmd/runner-exit internal/runner_exit -name '*.go')
 	go build -o $@ ./cmd/runner-exit
 
+$(BIN_DIR)/shellctl-runner: $(shell find cmd/runner internal/landlock internal/cmdutil -name '*.go')
+	go build -o $@ ./cmd/runner
+
+
 $(BIN_DIR)/dify-agent: $(shell find cmd/dify-agent-cli internal/agentcli internal/stubclient -name '*.go') $(shell find gen -name '*.go' 2>/dev/null)
 	go build -o $@ ./cmd/dify-agent-cli
 
@@ -83,12 +87,39 @@ integration-up:
 		fi; \
 		sleep 2; \
 	done
+	$(eval CONTAINER_NAME_NOISO := sandbox-rt-noiso-$(TEST_ID))
+	$(eval HOST_PORT_NOISO := $(shell python3 -c 'import socket; s=socket.socket(); s.bind(("",0)); print(s.getsockname()[1]); s.close()'))
+	$(eval AUTH_TOKEN_NOISO := test-token-noiso-$(TEST_ID))
+	@echo "Starting no-isolation container $(CONTAINER_NAME_NOISO) on port $(HOST_PORT_NOISO)..."
+	docker run -d --name $(CONTAINER_NAME_NOISO) \
+		-p $(HOST_PORT_NOISO):5004 \
+		-e SHELLCTL_AUTH_TOKEN=$(AUTH_TOKEN_NOISO) \
+		-e ENABLE_PATH_ISOLATION=false \
+		$(IMAGE_NAME)
+	@echo 'CONTAINER_NAME_NOISO=$(CONTAINER_NAME_NOISO)' >> $(STATE_FILE)
+	@echo 'HOST_PORT_NOISO=$(HOST_PORT_NOISO)' >> $(STATE_FILE)
+	@echo 'AUTH_TOKEN_NOISO=$(AUTH_TOKEN_NOISO)' >> $(STATE_FILE)
+	@for i in $$(seq 1 30); do \
+		if curl -sf http://localhost:$(HOST_PORT_NOISO)/healthz > /dev/null 2>&1; then \
+			echo "No-isolation runtime is ready on port $(HOST_PORT_NOISO)"; \
+			break; \
+		fi; \
+		if [ "$$i" -eq 30 ]; then \
+			echo "ERROR: no-isolation runtime not ready after 60s" >&2; \
+			docker logs $(CONTAINER_NAME_NOISO); \
+			docker rm -f $(CONTAINER_NAME_NOISO) 2>/dev/null; \
+			exit 1; \
+		fi; \
+		sleep 2; \
+	done
 
 integration-test:
 	@test -f $(STATE_FILE) || { echo "ERROR: run 'make integration-up' first" >&2; exit 1; }
 	@. ./$(STATE_FILE); \
 	SHELLCTL_GO_URL=http://localhost:$$HOST_PORT \
 	SHELLCTL_TEST_TOKEN=$$AUTH_TOKEN \
+	SHELLCTL_GO_URL_NO_ISOLATION=http://localhost:$$HOST_PORT_NOISO \
+	SHELLCTL_TEST_TOKEN_NO_ISOLATION=$$AUTH_TOKEN_NOISO \
 	go test -tags=integration -v -count=1 -timeout=300s ./tests/...
 
 integration-logs:
@@ -99,6 +130,7 @@ integration-down:
 	@if [ -f $(STATE_FILE) ]; then \
 		. ./$(STATE_FILE); \
 		docker rm -f $$CONTAINER_NAME 2>/dev/null || true; \
+		docker rm -f $$CONTAINER_NAME_NOISO 2>/dev/null || true; \
 		rm -f $(STATE_FILE); \
 	fi
 
diff --git a/dify-agent-runtime/README.md b/dify-agent-runtime/README.md
index 6b96ca76435..74e796a1d5c 100644
--- a/dify-agent-runtime/README.md
+++ b/dify-agent-runtime/README.md
@@ -25,11 +25,12 @@ internal/
 make build
 ```
 
-Produces three binaries in `bin/`:
+Produces binaries in `bin/`:
 
 - `shellctl` — the main server (`shellctl serve --listen 0.0.0.0:5004`)
 - `shellctl-sanitize-pty` — PTY sanitizer for tmux pipe-pane
 - `shellctl-runner-exit` — exit state writer
+- `shellctl-runner` — job runner with integrated Landlock isolation
 
 ### Building docker image
 
@@ -62,6 +63,30 @@ make gen-cli-help
 make test
 ```
 
+## Path Isolation
+
+Each agent job runs inside a Landlock sandbox that restricts filesystem access:
+
+| Access | Paths (defaults) |
+|--------|------------------|
+| **Read-Write** | `$HOME` (always, includes `$CWD/.tmp` as `TMPDIR`) |
+| **Read-Write (dev)** | `/dev/null`, `/dev/zero`, `/dev/urandom`, `/dev/random`, `/dev/tty` |
+| **Read-Only + Exec** | `/usr`, `/bin`, `/sbin`, `/lib`, `/lib64`, `/etc`, `/proc`, `/opt/dify-agent-tools`, `/opt/homebrew`, `/snap` |
+| **Denied** | Everything else (`/tmp`, other agents' homes, `/var`, `/srv`, etc.) |
+
+The runner automatically creates `$CWD/.tmp` and sets `TMPDIR`, `TMP`, `TEMP` to it, so temp files stay isolated per workspace.
+
+### Environment Variables
+
+| Variable | Default | Description |
+|----------|---------|-------------|
+| `ENABLE_PATH_ISOLATION` | `true` | Set to `false` to disable Landlock entirely |
+| `LANDLOCK_RW_PATHS` | *(empty)* | Comma-separated RW directories (besides `$HOME`) |
+| `LANDLOCK_RO_PATHS` | `/usr,/bin,...` | Comma-separated RO+exec directories |
+| `LANDLOCK_RW_DEV_PATHS` | `/dev/null,...` | Comma-separated device files with RW access |
+
+Requires Linux ≥ 5.13. On unsupported kernels, a warning is printed to stderr.
+
 ## Dependencies
 
 - Go 1.23+
diff --git a/dify-agent-runtime/cmd/runner-exit/main.go b/dify-agent-runtime/cmd/runner-exit/main.go
index b1eb2344a8b..4464dc86a05 100644
--- a/dify-agent-runtime/cmd/runner-exit/main.go
+++ b/dify-agent-runtime/cmd/runner-exit/main.go
@@ -5,8 +5,8 @@ package main
 import (
 	"flag"
 	"fmt"
-	"os"
 
+	"github.com/langgenius/dify/dify-agent-runtime/internal/cmdutil"
 	runnerexit "github.com/langgenius/dify/dify-agent-runtime/internal/runner_exit"
 )
 
@@ -19,12 +19,11 @@ func main() {
 	flag.Parse()
 
 	if *stateDir == "" || *jobID == "" || *endedAt == "" {
-		fmt.Fprintf(os.Stderr, "shellctl-runner-exit: --state-dir, --job-id, and --ended-at are required\n")
-		os.Exit(1)
+		cmdutil.HandleError(fmt.Errorf("missing flags"), 1, "--state-dir, --job-id, and --ended-at are required")
 	}
 
-	if err := runnerexit.RecordRunnerExit(*stateDir, *jobID, *exitCode, *endedAt, *busyTimeoutMs); err != nil {
-		fmt.Fprintf(os.Stderr, "shellctl-runner-exit: %v\n", err)
-		os.Exit(1)
-	}
+	cmdutil.HandleError(
+		runnerexit.RecordRunnerExit(*stateDir, *jobID, *exitCode, *endedAt, *busyTimeoutMs),
+		1, "record runner exit",
+	)
 }
diff --git a/dify-agent-runtime/cmd/runner/main.go b/dify-agent-runtime/cmd/runner/main.go
new file mode 100644
index 00000000000..910eff8a9d2
--- /dev/null
+++ b/dify-agent-runtime/cmd/runner/main.go
@@ -0,0 +1,289 @@
+// shellctl-runner is the Go replacement for the previously generated bash+python
+// runner script.  It is invoked by tmux as:
+//
+//	shellctl-runner <job_dir> <job_id> <cwd>
+//
+// The binary operates in two modes:
+//
+//  1. Parent mode (default): waits for start-gate, loads env, forks child,
+//     waits for exit, writes exit artifacts.
+//  2. Child mode (--exec flag): applies Landlock restrictions, then exec's
+//     the user script.
+//
+// This eliminates the bash/python dependency chain and integrates Landlock
+// directly.
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"os/signal"
+	"path/filepath"
+	"strings"
+	"syscall"
+	"time"
+
+	"github.com/langgenius/dify/dify-agent-runtime/internal/cmdutil"
+	"github.com/langgenius/dify/dify-agent-runtime/internal/envvar"
+	"github.com/langgenius/dify/dify-agent-runtime/internal/landlock"
+)
+
+func main() {
+	if len(os.Args) > 1 && os.Args[1] == "--exec" {
+		childMode()
+		return
+	}
+	parentMode()
+}
+
+// parentMode is the entry point when called by tmux.
+// Args: shellctl-runner <job_dir> <job_id> <cwd>
+func parentMode() {
+	if len(os.Args) < 4 {
+		cmdutil.HandleError(fmt.Errorf("bad args"), 125, "usage: shellctl-runner <job_dir> <job_id> <cwd>")
+	}
+
+	jobDir := os.Args[1]
+	// jobID := os.Args[2] // unused in parent but passed for compat
+	cwd := os.Args[3]
+
+	scriptPath := filepath.Join(jobDir, "script")
+	envPath := filepath.Join(jobDir, ".job-env.json")
+	startGate := filepath.Join(jobDir, "start-gate")
+	exitCodePath := filepath.Join(jobDir, "runner-exit-code")
+	endedAtPath := filepath.Join(jobDir, "runner-ended-at")
+
+	// Wait for start-gate.
+	for {
+		if _, err := os.Stat(startGate); err == nil {
+			break
+		}
+		time.Sleep(50 * time.Millisecond)
+	}
+
+	// Load environment overlay from JSON.
+	env := os.Environ()
+	// Remove internal shellctl vars from inherited env.
+	env = filterEnv(env, []string{
+		"TMUX",
+		"SHELLCTL_STATE_DIR",
+		"SHELLCTL_RUNTIME_DIR",
+		"SHELLCTL_TMUX_SOCKET",
+		"SHELLCTL_RUNNER",
+		"SHELLCTL_AUTH_TOKEN",
+	})
+
+	envOverlay := loadEnvJSON(envPath)
+	env = mergeEnv(env, envOverlay)
+
+	// Ensure HOME exists.
+	home := envGet(env, "HOME")
+	if home != "" {
+		cmdutil.HandleError(os.MkdirAll(home, 0755), 125, "mkdir HOME %s", home)
+	}
+
+	// Create a per-workspace temp directory under cwd and inject TMPDIR.
+	// This avoids granting RW access to the shared /tmp.
+	agentTmp := filepath.Join(cwd, ".tmp")
+	cmdutil.HandleError(os.MkdirAll(agentTmp, 0755), 125, "mkdir TMPDIR %s", agentTmp)
+	env = setEnvIfEmpty(env, "TMPDIR", agentTmp)
+	env = setEnvIfEmpty(env, "TMP", agentTmp)
+	env = setEnvIfEmpty(env, "TEMP", agentTmp)
+
+	// Determine if path isolation is enabled.
+	enableIsolation := envvar.PathIsolationEnabled()
+
+	// Build child command: re-exec self in --exec mode.
+	self, _ := os.Executable()
+	childArgs := []string{"--exec", scriptPath, cwd}
+	if enableIsolation {
+		childArgs = append([]string{"--exec", "--landlock"}, childArgs[1:]...)
+	}
+
+	cmd := exec.Command(self, childArgs...)
+	cmd.Env = env
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Dir = cwd
+
+	// Forward signals to child.
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
+	go func() {
+		for sig := range sigCh {
+			if cmd.Process != nil {
+				_ = cmd.Process.Signal(sig)
+			}
+		}
+	}()
+
+	err := cmd.Run()
+
+	exitCode := 0
+	if err != nil {
+		if exitErr, ok := err.(*exec.ExitError); ok {
+			exitCode = exitErr.ExitCode()
+		} else {
+			exitCode = 125
+		}
+	}
+
+	endedAt := time.Now().UTC().Format("2006-01-02T15:04:05Z")
+
+	writeAtomic(exitCodePath, fmt.Sprintf("%d", exitCode))
+	writeAtomic(endedAtPath, endedAt)
+
+	os.Exit(exitCode)
+}
+
+// childMode applies Landlock (if --landlock flag) and exec's the user script.
+// Args: shellctl-runner --exec [--landlock] <script_path> <cwd>
+func childMode() {
+	args := os.Args[2:] // skip program name and "--exec"
+	applyLandlockFlag := false
+
+	if len(args) > 0 && args[0] == "--landlock" {
+		applyLandlockFlag = true
+		args = args[1:]
+	}
+
+	if len(args) < 2 {
+		cmdutil.HandleError(fmt.Errorf("bad args"), 125, "--exec: missing script_path and cwd")
+	}
+
+	scriptPath := args[0]
+	cwd := args[1]
+
+	// chdir
+	cmdutil.HandleError(os.Chdir(cwd), 111, "chdir %s", cwd)
+
+	// Determine argv for exec.
+	argv := buildExecArgv(scriptPath)
+
+	// Resolve binary before Landlock (PATH search).
+	binary, err := exec.LookPath(argv[0])
+	cmdutil.HandleError(err, 127, "%s: not found", argv[0])
+
+	// Apply Landlock if requested.
+	if applyLandlockFlag {
+		home := os.Getenv("HOME")
+		jobDir := filepath.Dir(scriptPath)
+		cfg := landlock.ConfigFromEnv(home, cwd, jobDir)
+		if err := landlock.Restrict(cfg); err != nil {
+			if errors.Is(err, landlock.ErrNotSupported) {
+				fmt.Fprintf(os.Stderr, "shellctl-runner: WARNING: %v — running without filesystem isolation\n", err)
+			} else {
+				cmdutil.HandleError(err, 125, "landlock restrict")
+			}
+		}
+	}
+
+	// exec replaces the current process.
+	cmdutil.HandleError(syscall.Exec(binary, argv, os.Environ()), 126, "exec %s", binary)
+}
+
+// buildExecArgv determines whether the script has a shebang or needs sh.
+func buildExecArgv(scriptPath string) []string {
+	f, err := os.Open(scriptPath)
+	if err != nil {
+		return []string{"sh", scriptPath}
+	}
+	defer func() { _ = f.Close() }()
+
+	buf := make([]byte, 2)
+	n, _ := f.Read(buf)
+	if n == 2 && string(buf) == "#!" {
+		// Has shebang — make executable and run directly.
+		_ = os.Chmod(scriptPath, 0755)
+		return []string{scriptPath}
+	}
+	return []string{"sh", scriptPath}
+}
+
+// loadEnvJSON reads a JSON object from path and returns key=value pairs.
+func loadEnvJSON(path string) map[string]string {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		cmdutil.HandleError(err, 125, "read env json %s", path)
+	}
+	var m map[string]string
+	if err := json.Unmarshal(data, &m); err != nil {
+		cmdutil.HandleError(err, 125, "parse env json %s", path)
+	}
+	return m
+}
+
+// filterEnv removes entries with the given key prefixes from env.
+func filterEnv(env []string, remove []string) []string {
+	result := env[:0]
+	for _, e := range env {
+		skip := false
+		for _, r := range remove {
+			if strings.HasPrefix(e, r+"=") {
+				skip = true
+				break
+			}
+		}
+		if !skip {
+			result = append(result, e)
+		}
+	}
+	return result
+}
+
+// mergeEnv applies overlay key=value pairs onto the env slice.
+func mergeEnv(env []string, overlay map[string]string) []string {
+	for k, v := range overlay {
+		found := false
+		prefix := k + "="
+		for i, e := range env {
+			if strings.HasPrefix(e, prefix) {
+				env[i] = prefix + v
+				found = true
+				break
+			}
+		}
+		if !found {
+			env = append(env, prefix+v)
+		}
+	}
+	return env
+}
+
+// envGet retrieves a value from a []string env slice.
+func envGet(env []string, key string) string {
+	prefix := key + "="
+	for _, e := range env {
+		if strings.HasPrefix(e, prefix) {
+			return e[len(prefix):]
+		}
+	}
+	return ""
+}
+
+// setEnvIfEmpty sets key=value in the env slice only if the key is not already present.
+func setEnvIfEmpty(env []string, key, value string) []string {
+	if envGet(env, key) != "" {
+		return env
+	}
+	return append(env, key+"="+value)
+}
+
+// writeAtomic writes value to dest via a temp file + rename.
+func writeAtomic(dest, value string) {
+	tmp := fmt.Sprintf("%s.tmp.%d", dest, os.Getpid())
+	if err := os.WriteFile(tmp, []byte(value+"\n"), 0644); err != nil {
+		fmt.Fprintf(os.Stderr, "shellctl-runner: write %s: %v\n", tmp, err)
+		return
+	}
+	if err := os.Rename(tmp, dest); err != nil {
+		fmt.Fprintf(os.Stderr, "shellctl-runner: rename %s -> %s: %v\n", tmp, dest, err)
+	}
+}
diff --git a/dify-agent-runtime/cmd/sanitize-pty/main.go b/dify-agent-runtime/cmd/sanitize-pty/main.go
index 298071f2f19..2a653060de8 100644
--- a/dify-agent-runtime/cmd/sanitize-pty/main.go
+++ b/dify-agent-runtime/cmd/sanitize-pty/main.go
@@ -5,9 +5,9 @@ package main
 
 import (
 	"flag"
-	"fmt"
 	"os"
 
+	"github.com/langgenius/dify/dify-agent-runtime/internal/cmdutil"
 	"github.com/langgenius/dify/dify-agent-runtime/internal/sanitize"
 )
 
@@ -15,8 +15,5 @@ func main() {
 	readyFile := flag.String("ready-file", "", "path to touch before reading stdin")
 	flag.Parse()
 
-	if err := sanitize.Run(*readyFile, os.Stdin, os.Stdout); err != nil {
-		fmt.Fprintf(os.Stderr, "shellctl-sanitize-pty: %v\n", err)
-		os.Exit(1)
-	}
+	cmdutil.HandleError(sanitize.Run(*readyFile, os.Stdin, os.Stdout), 1, "sanitize-pty")
 }
diff --git a/dify-agent-runtime/docker/Dockerfile b/dify-agent-runtime/docker/Dockerfile
index 97f8ee81c99..798e36a8d41 100644
--- a/dify-agent-runtime/docker/Dockerfile
+++ b/dify-agent-runtime/docker/Dockerfile
@@ -14,6 +14,7 @@ COPY . .
 RUN CGO_ENABLED=0 go build -o /bin/shellctl ./cmd/shellctl && \
     CGO_ENABLED=0 go build -o /bin/shellctl-sanitize-pty ./cmd/sanitize-pty && \
     CGO_ENABLED=0 go build -o /bin/shellctl-runner-exit ./cmd/runner-exit && \
+    CGO_ENABLED=0 go build -o /bin/shellctl-runner ./cmd/runner && \
     CGO_ENABLED=0 go build -o /bin/dify-agent ./cmd/dify-agent-cli
 
 # ── Runtime stage ────────────────────────────────────────────────────────────
@@ -65,6 +66,7 @@ RUN python -m pip install --no-cache-dir "uv==${UV_VERSION}"
 COPY --from=go-builder /bin/shellctl /usr/local/bin/shellctl
 COPY --from=go-builder /bin/shellctl-sanitize-pty /usr/local/bin/shellctl-sanitize-pty
 COPY --from=go-builder /bin/shellctl-runner-exit /usr/local/bin/shellctl-runner-exit
+COPY --from=go-builder /bin/shellctl-runner /usr/local/bin/shellctl-runner
 COPY --from=go-builder /bin/dify-agent /usr/local/bin/dify-agent
 
 RUN useradd --create-home --shell /bin/sh dify \
diff --git a/dify-agent-runtime/go.mod b/dify-agent-runtime/go.mod
index 80f71bfb98b..9cf551446c4 100644
--- a/dify-agent-runtime/go.mod
+++ b/dify-agent-runtime/go.mod
@@ -3,6 +3,7 @@ module github.com/langgenius/dify/dify-agent-runtime
 go 1.26
 
 require (
+	github.com/landlock-lsm/go-landlock v0.9.0
 	github.com/spf13/cobra v1.10.2
 	google.golang.org/grpc v1.82.0
 	google.golang.org/protobuf v1.36.11
@@ -22,6 +23,7 @@ require (
 	golang.org/x/sys v0.43.0 // indirect
 	golang.org/x/text v0.36.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20260414002931-afd174a4e478 // indirect
+	kernel.org/pub/linux/libs/security/libcap/psx v1.2.77 // indirect
 	modernc.org/libc v1.65.7 // indirect
 	modernc.org/mathutil v1.7.1 // indirect
 	modernc.org/memory v1.11.0 // indirect
diff --git a/dify-agent-runtime/go.sum b/dify-agent-runtime/go.sum
index 91aa0612cef..15705eabb41 100644
--- a/dify-agent-runtime/go.sum
+++ b/dify-agent-runtime/go.sum
@@ -17,6 +17,8 @@ github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/landlock-lsm/go-landlock v0.9.0 h1:2q8G8yx9Hsd5bV+R6PJfgQl0zszNxC8KO+SIqGwfxlw=
+github.com/landlock-lsm/go-landlock v0.9.0/go.mod h1:mn5GSi81Jf7yMs5WSi+SUi4sUeNLUGVdbT4Id6wXNQw=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/ncruces/go-strftime v0.1.9 h1:bY0MQC28UADQmHmaF5dgpLmImcShSi2kHU9XLdhx/f4=
@@ -65,6 +67,8 @@ google.golang.org/grpc v1.82.0/go.mod h1:yzTZ1TB1Z3SG+LIYaI+WiE8D5+PZ3ArnrSp8zF3
 google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
 google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+kernel.org/pub/linux/libs/security/libcap/psx v1.2.77 h1:Z06sMOzc0GNCwp6efaVrIrz4ywGJ1v+DP0pjVkOfDuA=
+kernel.org/pub/linux/libs/security/libcap/psx v1.2.77/go.mod h1:+l6Ee2F59XiJ2I6WR5ObpC1utCQJZ/VLsEbQCD8RG24=
 modernc.org/cc/v4 v4.26.1 h1:+X5NtzVBn0KgsBCBe+xkDC7twLb/jNVj9FPgiwSQO3s=
 modernc.org/cc/v4 v4.26.1/go.mod h1:uVtb5OGqUKpoLWhqwNQo/8LwvoiEBLvZXIQ/SmO6mL0=
 modernc.org/ccgo/v4 v4.28.0 h1:rjznn6WWehKq7dG4JtLRKxb52Ecv8OUGah8+Z/SfpNU=
diff --git a/dify-agent-runtime/internal/agentcli/env.go b/dify-agent-runtime/internal/agentcli/env.go
index 8e7962f90f8..1db58b057d2 100644
--- a/dify-agent-runtime/internal/agentcli/env.go
+++ b/dify-agent-runtime/internal/agentcli/env.go
@@ -9,14 +9,16 @@ import (
 	"net/url"
 	"os"
 	"strings"
+
+	"github.com/langgenius/dify/dify-agent-runtime/internal/envvar"
 )
 
 const (
-	EnvAPIBaseURL = "DIFY_AGENT_STUB_API_BASE_URL"
-	EnvAuthJWE    = "DIFY_AGENT_STUB_AUTH_JWE"
-	EnvDriveBase  = "DIFY_AGENT_STUB_DRIVE_BASE"
+	EnvAPIBaseURL = envvar.EnvAgentStubAPIBaseURL
+	EnvAuthJWE    = envvar.EnvAgentStubAuthJWE
+	EnvDriveBase  = envvar.EnvAgentStubDriveBase
 
-	DefaultDriveBase = "/mnt/drive"
+	DefaultDriveBase = envvar.DefaultDriveBase
 )
 
 // Environment holds validated Agent Stub connection parameters.
diff --git a/dify-agent-runtime/internal/cmdutil/cmdutil.go b/dify-agent-runtime/internal/cmdutil/cmdutil.go
new file mode 100644
index 00000000000..826cf45bc90
--- /dev/null
+++ b/dify-agent-runtime/internal/cmdutil/cmdutil.go
@@ -0,0 +1,19 @@
+package cmdutil
+
+import (
+	"fmt"
+	"os"
+)
+
+// HandleError checks err; if non-nil it prints a formatted message to stderr
+// and exits with the given code.  Callers can use it as a one-liner:
+//
+//	cmdutil.HandleError(os.MkdirAll(dir, 0755), 125, "mkdir %s", dir)
+func HandleError(err error, code int, format string, args ...any) {
+	if err == nil {
+		return
+	}
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(os.Stderr, "shellctl: %s: %v\n", msg, err)
+	os.Exit(code)
+}
diff --git a/dify-agent-runtime/internal/envvar/envvar.go b/dify-agent-runtime/internal/envvar/envvar.go
new file mode 100644
index 00000000000..7ecbd96b503
--- /dev/null
+++ b/dify-agent-runtime/internal/envvar/envvar.go
@@ -0,0 +1,56 @@
+// Package envvar centralizes all environment variable constants used by the
+// dify-agent-runtime binaries (shellctl, shellctl-runner, dify-agent CLI).
+package envvar
+
+import "os"
+
+// --- Path Isolation (Landlock) ---
+
+const (
+	// EnvEnablePathIsolation controls whether Landlock is applied at all.
+	EnvEnablePathIsolation = "ENABLE_PATH_ISOLATION"
+
+	// EnvRWPaths overrides the default RW directories (comma-separated).
+	EnvRWPaths = "LANDLOCK_RW_PATHS"
+
+	// EnvROPaths overrides the default RO+exec directories (comma-separated).
+	EnvROPaths = "LANDLOCK_RO_PATHS"
+
+	// EnvRWDevPaths overrides the default device files (comma-separated).
+	EnvRWDevPaths = "LANDLOCK_RW_DEV_PATHS"
+)
+
+// --- Agent Stub ---
+
+const (
+	// EnvAgentStubAPIBaseURL is the Agent Stub HTTP/gRPC endpoint.
+	EnvAgentStubAPIBaseURL = "DIFY_AGENT_STUB_API_BASE_URL"
+
+	// EnvAgentStubAuthJWE is the per-request JWE token for Agent Stub auth.
+	EnvAgentStubAuthJWE = "DIFY_AGENT_STUB_AUTH_JWE"
+
+	// EnvAgentStubDriveBase is the sandbox-local drive directory for the agent.
+	EnvAgentStubDriveBase = "DIFY_AGENT_STUB_DRIVE_BASE"
+
+	// DefaultDriveBase is the default Agent Stub drive mount point.
+	// currently unused.
+	DefaultDriveBase = "/mnt/drive"
+)
+
+// PathIsolationEnabled returns whether Landlock filesystem isolation is active.
+func PathIsolationEnabled() bool {
+	v, ok := os.LookupEnv(EnvEnablePathIsolation)
+	if !ok {
+		return true
+	}
+	return v == "true"
+}
+
+// SetPathIsolation explicitly enables or disables path isolation via env.
+func SetPathIsolation(enabled bool) {
+	if enabled {
+		_ = os.Setenv(EnvEnablePathIsolation, "true")
+	} else {
+		_ = os.Setenv(EnvEnablePathIsolation, "false")
+	}
+}
diff --git a/dify-agent-runtime/internal/landlock/config.go b/dify-agent-runtime/internal/landlock/config.go
new file mode 100644
index 00000000000..73cd791caa5
--- /dev/null
+++ b/dify-agent-runtime/internal/landlock/config.go
@@ -0,0 +1,95 @@
+package landlock
+
+import (
+	"os"
+	"strings"
+
+	"github.com/langgenius/dify/dify-agent-runtime/internal/envvar"
+)
+
+// Config holds the path lists for Landlock filesystem restrictions.
+type Config struct {
+	Home       string   // Agent's home directory (always RW).
+	Cwd        string   // Working directory (always RW, may differ from Home).
+	JobDir     string   // Job script directory (RO, auto-set by runner).
+	RWPaths    []string // Additional read-write directories.
+	ROPaths    []string // Read-only + execute directories.
+	RWDevPaths []string // Device files with read-write access.
+}
+
+var (
+	// DefaultRWPaths are directories granted read-write access besides HOME.
+	// Agent-specific paths (e.g. drive base) are added dynamically by the runner.
+	DefaultRWPaths = []string{}
+
+	// DefaultROPaths are directories granted read-only + execute access.
+	DefaultROPaths = []string{
+		"/usr",
+		"/bin",
+		"/sbin",
+		"/lib",
+		"/lib64",
+		"/etc",
+		"/proc",
+		"/opt/dify-agent-tools",
+		"/opt/homebrew",
+		"/snap",
+	}
+
+	// DefaultRWDevPaths are device files granted read-write access.
+	DefaultRWDevPaths = []string{
+		"/dev/null",
+		"/dev/zero",
+		"/dev/urandom",
+		"/dev/random",
+		"/dev/tty",
+	}
+)
+
+// DefaultConfig returns a Config with sensible defaults.
+func DefaultConfig(home, cwd, jobDir string) *Config {
+	return &Config{
+		Home:       home,
+		Cwd:        cwd,
+		JobDir:     jobDir,
+		RWPaths:    DefaultRWPaths,
+		ROPaths:    DefaultROPaths,
+		RWDevPaths: DefaultRWDevPaths,
+	}
+}
+
+// ConfigFromEnv returns a Config populated from environment variables,
+// falling back to defaults for any unset variable.
+//
+// If a variable is set (even to empty string), its value replaces the default.
+// Set to empty to grant no additional paths beyond $HOME.
+//
+//	LANDLOCK_RW_PATHS     — comma-separated RW dirs    (default: empty)
+//	LANDLOCK_RO_PATHS     — comma-separated RO dirs    (default: system paths)
+//	LANDLOCK_RW_DEV_PATHS — comma-separated dev files  (default: /dev/null,...)
+func ConfigFromEnv(home, cwd, jobDir string) *Config {
+	cfg := DefaultConfig(home, cwd, jobDir)
+
+	if v, ok := os.LookupEnv(envvar.EnvRWPaths); ok {
+		cfg.RWPaths = splitPaths(v)
+	}
+	if v, ok := os.LookupEnv(envvar.EnvROPaths); ok {
+		cfg.ROPaths = splitPaths(v)
+	}
+	if v, ok := os.LookupEnv(envvar.EnvRWDevPaths); ok {
+		cfg.RWDevPaths = splitPaths(v)
+	}
+
+	return cfg
+}
+
+func splitPaths(s string) []string {
+	var paths []string
+	for _, p := range strings.Split(s, ",") {
+		p = strings.TrimSpace(p)
+		if p != "" {
+			paths = append(paths, p)
+		}
+	}
+	return paths
+}
diff --git a/dify-agent-runtime/internal/landlock/landlock_linux.go b/dify-agent-runtime/internal/landlock/landlock_linux.go
new file mode 100644
index 00000000000..8249df278dd
--- /dev/null
+++ b/dify-agent-runtime/internal/landlock/landlock_linux.go
@@ -0,0 +1,80 @@
+//go:build linux
+
+package landlock
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"syscall"
+
+	golandlock "github.com/landlock-lsm/go-landlock/landlock"
+)
+
+// ErrNotSupported is returned when the kernel does not support Landlock.
+var ErrNotSupported = errors.New("landlock: not supported by kernel")
+
+// Restrict applies Landlock filesystem restrictions for the current process.
+//
+// It first tries strict enforcement.  If the kernel lacks Landlock support,
+// it falls back to BestEffort (which may silently degrade) and returns
+// ErrNotSupported so callers can log a warning.
+func Restrict(cfg *Config) error {
+	rules := buildRules(cfg)
+
+	if err := golandlock.V5.RestrictPaths(rules...); err != nil {
+		if !isNotSupported(err) {
+			return fmt.Errorf("landlock: restrict paths: %w", err)
+		}
+		if err2 := golandlock.V5.BestEffort().RestrictPaths(rules...); err2 != nil {
+			return fmt.Errorf("landlock: best-effort restrict paths: %w", err2)
+		}
+		return ErrNotSupported
+	}
+	return nil
+}
+
+func buildRules(cfg *Config) []golandlock.Rule {
+	// Collect RO paths that exist on this system.
+	roPaths := filterExisting(cfg.ROPaths)
+	if cfg.JobDir != "" {
+		roPaths = append(roPaths, cfg.JobDir)
+	}
+
+	// RW dirs: always include HOME and Cwd, plus configured extra paths.
+	rwDirs := []string{cfg.Home}
+	if cfg.Cwd != "" && cfg.Cwd != cfg.Home {
+		rwDirs = append(rwDirs, cfg.Cwd)
+	}
+	rwDirs = append(rwDirs, filterExisting(cfg.RWPaths)...)
+
+	// Device files with RW access.
+	rwDevFiles := filterExisting(cfg.RWDevPaths)
+
+	rules := []golandlock.Rule{
+		golandlock.RWDirs(rwDirs...),
+	}
+	if len(roPaths) > 0 {
+		rules = append(rules, golandlock.RODirs(roPaths...))
+	}
+	if len(rwDevFiles) > 0 {
+		rules = append(rules, golandlock.RWFiles(rwDevFiles...))
+	}
+	return rules
+}
+
+// isNotSupported reports whether err indicates the kernel does not support
+// Landlock (ENOSYS = syscall absent, EOPNOTSUPP = feature disabled).
+func isNotSupported(err error) bool {
+	return errors.Is(err, syscall.ENOSYS) || errors.Is(err, syscall.EOPNOTSUPP)
+}
+
+func filterExisting(paths []string) []string {
+	var out []string
+	for _, p := range paths {
+		if _, err := os.Stat(p); err == nil {
+			out = append(out, p)
+		}
+	}
+	return out
+}
diff --git a/dify-agent-runtime/internal/landlock/landlock_stub.go b/dify-agent-runtime/internal/landlock/landlock_stub.go
new file mode 100644
index 00000000000..d8bb3419a05
--- /dev/null
+++ b/dify-agent-runtime/internal/landlock/landlock_stub.go
@@ -0,0 +1,13 @@
+//go:build !linux
+
+package landlock
+
+import "errors"
+
+// ErrNotSupported is returned when the kernel does not support Landlock.
+var ErrNotSupported = errors.New("landlock: not supported by kernel")
+
+// Restrict is a no-op on non-Linux platforms; always returns ErrNotSupported.
+func Restrict(cfg *Config) error {
+	return ErrNotSupported
+}
diff --git a/dify-agent-runtime/internal/server/config.go b/dify-agent-runtime/internal/server/config.go
index 6b6258a8f54..226a44b8c43 100644
--- a/dify-agent-runtime/internal/server/config.go
+++ b/dify-agent-runtime/internal/server/config.go
@@ -8,25 +8,25 @@ import (
 )
 
 const (
-	DefaultListen                       = "127.0.0.1:8765"
-	DefaultTimeoutSeconds               = 30.0
-	DefaultMaxWaitTimeoutSeconds        = 600.0
-	DefaultIdleFlushSeconds             = 0.5
-	DefaultTerminalCols                 = 200
-	DefaultTerminalRows                 = 50
-	DefaultOutputLimitBytes             = 16 * 1024
-	MaxOutputLimitBytes                 = 512 * 1024
-	DefaultListLimit                    = 50
-	MaxListLimit                        = 200
-	DefaultTerminateGraceSeconds        = 10.0
-	DefaultGCIntervalSeconds            = 60.0
+	DefaultListen                        = "127.0.0.1:8765"
+	DefaultTimeoutSeconds                = 30.0
+	DefaultMaxWaitTimeoutSeconds         = 600.0
+	DefaultIdleFlushSeconds              = 0.5
+	DefaultTerminalCols                  = 200
+	DefaultTerminalRows                  = 50
+	DefaultOutputLimitBytes              = 16 * 1024
+	MaxOutputLimitBytes                  = 512 * 1024
+	DefaultListLimit                     = 50
+	MaxListLimit                         = 200
+	DefaultTerminateGraceSeconds         = 10.0
+	DefaultGCIntervalSeconds             = 60.0
 	DefaultGCFinishedJobRetentionSeconds = 300.0
-	DefaultPollInterval                 = 50 * time.Millisecond
-	DefaultPipeMonitorInterval          = 1 * time.Second
-	DefaultPipeReadyTimeout             = 10 * time.Second
-	DefaultSQLiteBusyTimeoutMs          = 5000
-	DefaultAuthTokenEnv                 = "SHELLCTL_AUTH_TOKEN"
-	HealthStatus                        = "ok"
+	DefaultPollInterval                  = 50 * time.Millisecond
+	DefaultPipeMonitorInterval           = 1 * time.Second
+	DefaultPipeReadyTimeout              = 10 * time.Second
+	DefaultSQLiteBusyTimeoutMs           = 5000
+	DefaultAuthTokenEnv                  = "SHELLCTL_AUTH_TOKEN"
+	HealthStatus                         = "ok"
 )
 
 // Config holds runtime configuration for the shellctl server.
diff --git a/dify-agent-runtime/internal/server/service.go b/dify-agent-runtime/internal/server/service.go
index d02e812a3b9..a859aa3474d 100644
--- a/dify-agent-runtime/internal/server/service.go
+++ b/dify-agent-runtime/internal/server/service.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -826,98 +827,35 @@ func (s *Service) cleanupStarting(jobID, jobDir string) {
 }
 
 func (s *Service) installRunner() {
-	script := s.runnerScriptSource()
-	_ = os.WriteFile(s.config.RunnerPath(), []byte(script), 0755)
-}
+	// The runner is now a pre-built Go binary (shellctl-runner).
+	// Create a symlink at the expected RunnerPath so tmux can invoke it.
+	dst := s.config.RunnerPath()
+	_ = os.Remove(dst) // remove stale script/symlink
 
-func (s *Service) runnerScriptSource() string {
-	// The runner script is a bash wrapper that waits for the start-gate,
-	// then delegates env loading + exec to a Python bootstrap so that
-	// JSON env values (including multi-line strings) are applied verbatim.
-	// The Python helper exec's the target process so SIGINT semantics
-	// match running the script directly in the tmux pane.
-	return `#!/usr/bin/env bash
-set -uo pipefail
+	// Look for the binary next to the main shellctl binary first,
+	// then fall back to PATH lookup.
+	src := ""
+	selfExe, _ := os.Executable()
+	if selfExe != "" {
+		candidate := filepath.Join(filepath.Dir(selfExe), "shellctl-runner")
+		if _, err := os.Stat(candidate); err == nil {
+			src = candidate
+		}
+	}
+	if src == "" {
+		if p, err := exec.LookPath("shellctl-runner"); err == nil {
+			src = p
+		}
+	}
 
-JOB_DIR="$1"
-JOB_ID="$2"
-CWD="$3"
-SCRIPT_PATH="$JOB_DIR/script"
-ENV_PATH="$JOB_DIR/.job-env.json"
-START_GATE="$JOB_DIR/start-gate"
-RUNNER_EXIT_CODE_PATH="$JOB_DIR/runner-exit-code"
-RUNNER_ENDED_AT_PATH="$JOB_DIR/runner-ended-at"
-
-write_atomic() {
-  local dest="$1"
-  local value="$2"
-  local tmp="${dest}.tmp.$$"
-  printf '%s\n' "$value" > "$tmp"
-  mv "$tmp" "$dest"
-}
-
-while [ ! -e "$START_GATE" ]; do
-  sleep 0.05
-done
-
-unset TMUX
-unset SHELLCTL_STATE_DIR
-unset SHELLCTL_RUNTIME_DIR
-unset SHELLCTL_TMUX_SOCKET
-unset SHELLCTL_RUNNER
-unset SHELLCTL_AUTH_TOKEN
-
-# Use Python bootstrap to load JSON env verbatim and exec the target.
-# This avoids depending on jq and correctly handles multi-line values.
-python3 -c '
-import json, os, stat, sys
-from pathlib import Path
-
-script_path = Path(sys.argv[1])
-cwd = sys.argv[2]
-env_path = Path(sys.argv[3])
-
-env = os.environ.copy()
-if env_path.exists():
-    env.update(json.loads(env_path.read_text(encoding="utf-8")))
-
-try:
-    os.chdir(cwd)
-except OSError:
-    raise SystemExit(111)
-
-# Ensure HOME directory exists (agent backend may set a per-agent HOME).
-home = env.get("HOME", "")
-if home and not os.path.isdir(home):
-    os.makedirs(home, exist_ok=True)
-
-with script_path.open("r", encoding="utf-8") as handle:
-    first_line = handle.readline()
-
-if first_line.startswith("#!"):
-    script_path.chmod(script_path.stat().st_mode | stat.S_IXUSR)
-    argv = [str(script_path)]
-else:
-    argv = ["sh", str(script_path)]
-
-try:
-    os.execvpe(argv[0], argv, env)
-except FileNotFoundError as exc:
-    print(f"{argv[0]}: {exc.strerror}", file=sys.stderr)
-    raise SystemExit(127) from exc
-except OSError as exc:
-    print(f"{argv[0]}: {exc.strerror}", file=sys.stderr)
-    raise SystemExit(126) from exc
-' "$SCRIPT_PATH" "$CWD" "$ENV_PATH"
-EXIT_CODE=$?
-
-ENDED_AT="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
-
-write_atomic "$RUNNER_EXIT_CODE_PATH" "$EXIT_CODE"
-write_atomic "$RUNNER_ENDED_AT_PATH" "$ENDED_AT"
-
-exit "$EXIT_CODE"
-`
+	if src != "" {
+		// Prefer symlink; fall back to copy path reference.
+		if err := os.Symlink(src, dst); err != nil {
+			// If symlink fails (e.g., cross-device), write a tiny shell wrapper.
+			wrapper := fmt.Sprintf("#!/bin/sh\nexec %q \"$@\"\n", src)
+			_ = os.WriteFile(dst, []byte(wrapper), 0755)
+		}
+	}
 }
 
 // Helpers
diff --git a/dify-agent-runtime/tests/acceptance_test.go b/dify-agent-runtime/tests/acceptance_test.go
index cfd5bd1f4be..caf3b773791 100644
--- a/dify-agent-runtime/tests/acceptance_test.go
+++ b/dify-agent-runtime/tests/acceptance_test.go
@@ -26,6 +26,9 @@ var (
 	goURL     = envOrDefault("SHELLCTL_GO_URL", "http://localhost:15005")
 	authToken = envOrDefault("SHELLCTL_TEST_TOKEN", "test-token-123")
 
+	goURLNoIsolation     = os.Getenv("SHELLCTL_GO_URL_NO_ISOLATION")
+	authTokenNoIsolation = os.Getenv("SHELLCTL_TEST_TOKEN_NO_ISOLATION")
+
 	httpClient = &http.Client{Timeout: 120 * time.Second}
 )
 
@@ -41,6 +44,13 @@ func targets() []target {
 	}
 }
 
+func noIsolationTarget() (target, bool) {
+	if goURLNoIsolation == "" {
+		return target{}, false
+	}
+	return target{name: "go-no-isolation", baseURL: goURLNoIsolation}, true
+}
+
 func TestMain(m *testing.M) {
 	// Warmup: wait for both servers to be ready before running tests
 	for _, tgt := range targets() {
@@ -49,10 +59,19 @@ func TestMain(m *testing.M) {
 			os.Exit(1)
 		}
 	}
+	if tgt, ok := noIsolationTarget(); ok {
+		if !waitForServer(tgt) {
+			fmt.Fprintf(os.Stderr, "ERROR: %s server not ready at %s\n", tgt.name, tgt.baseURL)
+			os.Exit(1)
+		}
+	}
 
 	for _, tgt := range targets() {
 		warmupJob(tgt)
 	}
+	if tgt, ok := noIsolationTarget(); ok {
+		warmupJobWithToken(tgt, authTokenNoIsolation)
+	}
 	os.Exit(m.Run())
 }
 
@@ -489,6 +508,166 @@ func TestJobNotFound(t *testing.T) {
 	}
 }
 
+// --- Landlock Tests ---
+// These tests verify that shellctl-run restricts filesystem access
+// so each agent job can only write within its own HOME directory while still
+// being able to execute system commands.
+
+func TestLandlockCanWriteHome(t *testing.T) {
+	for _, tgt := range targets() {
+		t.Run(tgt.name, func(t *testing.T) {
+			// The job runs with HOME set; writing a file inside HOME should succeed.
+			result := runJob(t, tgt, map[string]any{
+				"script":  "touch \"$HOME/landlock-test-file\" && echo ok",
+				"env":     map[string]string{"HOME": "/home/dify"},
+				"timeout": 10,
+			})
+			assertJobDone(t, result)
+			assertExitCode(t, result, 0)
+			output := result["output"].(string)
+			if !strings.Contains(output, "ok") {
+				t.Errorf("expected write to HOME to succeed, got %q", output)
+			}
+		})
+	}
+}
+
+func TestLandlockCanReadSystemBinaries(t *testing.T) {
+	for _, tgt := range targets() {
+		t.Run(tgt.name, func(t *testing.T) {
+			// System binaries should remain executable (RO access to /usr, /bin).
+			result := runJob(t, tgt, map[string]any{
+				"script":  "which ls && ls /usr/bin/env && echo ok",
+				"env":     map[string]string{"HOME": "/home/dify"},
+				"timeout": 10,
+			})
+			assertJobDone(t, result)
+			assertExitCode(t, result, 0)
+			output := result["output"].(string)
+			if !strings.Contains(output, "ok") {
+				t.Errorf("expected system binary access to succeed, got %q", output)
+			}
+		})
+	}
+}
+
+func TestLandlockCanWriteTmpdir(t *testing.T) {
+	for _, tgt := range targets() {
+		t.Run(tgt.name, func(t *testing.T) {
+			// TMPDIR ($CWD/.tmp) should be writable; /tmp should be denied.
+			result := runJob(t, tgt, map[string]any{
+				"script":  "echo TMPDIR=$TMPDIR && touch $TMPDIR/landlock-tmp-test && echo tmpdir_ok && touch /tmp/landlock-denied 2>&1; echo tmp_exit=$?",
+				"env":     map[string]string{"HOME": "/home/dify"},
+				"timeout": 10,
+			})
+			assertJobDone(t, result)
+			output := result["output"].(string)
+			if !strings.Contains(output, "tmpdir_ok") {
+				t.Errorf("expected write to $TMPDIR to succeed, got %q", output)
+			}
+			if !strings.Contains(output, "tmp_exit=1") && !strings.Contains(output, "Permission denied") {
+				t.Errorf("expected write to /tmp to be denied, got %q", output)
+			}
+		})
+	}
+}
+
+func TestLandlockCannotWriteOutsideHome(t *testing.T) {
+	for _, tgt := range targets() {
+		t.Run(tgt.name, func(t *testing.T) {
+			// Writing outside HOME (e.g., /opt) should be denied by Landlock.
+			result := runJob(t, tgt, map[string]any{
+				"script":  "touch /opt/landlock-denied 2>&1; echo exit=$?",
+				"env":     map[string]string{"HOME": "/home/dify"},
+				"timeout": 10,
+			})
+			assertJobDone(t, result)
+			output := result["output"].(string)
+			// The touch should fail with "Permission denied" or similar,
+			// and exit code should be non-zero.
+			if strings.Contains(output, "exit=0") {
+				t.Errorf("expected write to /opt to be denied, but it succeeded: %q", output)
+			}
+		})
+	}
+}
+
+func TestLandlockCannotReadOtherAgentHome(t *testing.T) {
+	for _, tgt := range targets() {
+		t.Run(tgt.name, func(t *testing.T) {
+			// First, create a file in one agent's home.
+			setup := runJob(t, tgt, map[string]any{
+				"script":  "mkdir -p /home/agent-a && touch /home/agent-a/secret",
+				"env":     map[string]string{"HOME": "/home/agent-a"},
+				"timeout": 10,
+			})
+			assertJobDone(t, setup)
+			assertExitCode(t, setup, 0)
+
+			// Now run as a different agent and try to read the other's file.
+			result := runJob(t, tgt, map[string]any{
+				"script":  "cat /home/agent-a/secret 2>&1; echo exit=$?",
+				"env":     map[string]string{"HOME": "/home/agent-b"},
+				"timeout": 10,
+			})
+			assertJobDone(t, result)
+			output := result["output"].(string)
+			if strings.Contains(output, "exit=0") {
+				t.Errorf("expected read of other agent's file to be denied, but it succeeded: %q", output)
+			}
+		})
+	}
+}
+
+// --- Landlock Disable / Bypass Tests ---
+
+// TestLandlockDisabledAllowsWriteOutsideHome uses the pre-started no-isolation
+// container (ENABLE_PATH_ISOLATION=false) and verifies that isolation is off.
+func TestLandlockDisabledAllowsWriteOutsideHome(t *testing.T) {
+	tgt, ok := noIsolationTarget()
+	if !ok {
+		t.Skip("SHELLCTL_GO_URL_NO_ISOLATION not set; no-isolation container not available")
+	}
+
+	// With isolation disabled, writes to /tmp should succeed.
+	// /tmp is world-writable (Unix perms) but blocked by Landlock when enabled.
+	result := runJobWithToken(t, tgt, authTokenNoIsolation, map[string]any{
+		"script":  "touch /tmp/landlock-disabled-test && echo write_ok",
+		"env":     map[string]string{"HOME": "/home/dify"},
+		"timeout": 10,
+	})
+	assertJobDone(t, result)
+	assertExitCode(t, result, 0)
+	output := result["output"].(string)
+	if !strings.Contains(output, "write_ok") {
+		t.Errorf("expected write to /tmp to succeed with isolation disabled, got %q", output)
+	}
+}
+
+// TestLandlockEnvBypassBlocked verifies that a caller cannot set
+// ENABLE_PATH_ISOLATION=false in job env to escape the sandbox.
+func TestLandlockEnvBypassBlocked(t *testing.T) {
+	for _, tgt := range targets() {
+		t.Run(tgt.name, func(t *testing.T) {
+			// Attempt to bypass Landlock by passing the disable flag in job env.
+			result := runJob(t, tgt, map[string]any{
+				"script": "touch /opt/landlock-bypass-test 2>&1; echo exit=$?",
+				"env": map[string]string{
+					"HOME":                  "/home/dify",
+					"ENABLE_PATH_ISOLATION": "false",
+				},
+				"timeout": 10,
+			})
+			assertJobDone(t, result)
+			output := result["output"].(string)
+			// The write should still be denied despite the env override attempt.
+			if strings.Contains(output, "exit=0") {
+				t.Errorf("expected write to /opt to be DENIED even with ENABLE_PATH_ISOLATION=false in job env, but it succeeded: %q", output)
+			}
+		})
+	}
+}
+
 // --- Helpers ---
 
 func runJob(t *testing.T, tgt target, payload map[string]any) map[string]any {
@@ -585,3 +764,46 @@ func envOrDefault(key, defaultVal string) string {
 	}
 	return defaultVal
 }
+
+func warmupJobWithToken(tgt target, token string) {
+	warmupClient := &http.Client{Timeout: 180 * time.Second}
+	payload, _ := json.Marshal(map[string]any{
+		"script":  "echo warmup",
+		"timeout": 10,
+	})
+	for attempt := 0; attempt < 3; attempt++ {
+		req, _ := http.NewRequest("POST", tgt.baseURL+"/v1/jobs/run", bytes.NewReader(payload))
+		req.Header.Set("Content-Type", "application/json")
+		req.Header.Set("Authorization", "Bearer "+token)
+		resp, err := warmupClient.Do(req)
+		if err != nil {
+			time.Sleep(2 * time.Second)
+			continue
+		}
+		io.Copy(io.Discard, resp.Body)
+		resp.Body.Close()
+		if resp.StatusCode == 200 {
+			return
+		}
+		time.Sleep(2 * time.Second)
+	}
+}
+
+func runJobWithToken(t *testing.T, tgt target, token string, payload map[string]any) map[string]any {
+	t.Helper()
+	body, _ := json.Marshal(payload)
+	req, _ := http.NewRequest("POST", tgt.baseURL+"/v1/jobs/run", bytes.NewReader(body))
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", "Bearer "+token)
+	resp, err := httpClient.Do(req)
+	if err != nil {
+		t.Fatalf("[%s] POST /v1/jobs/run failed: %v", tgt.name, err)
+	}
+	assertStatus(t, resp, 200)
+	respBody := readBody(t, resp)
+	var result map[string]any
+	if err := json.Unmarshal(respBody, &result); err != nil {
+		t.Fatalf("[%s] failed to parse run response: %v\nbody: %s", tgt.name, err, string(respBody))
+	}
+	return result
+}