Merge pull request 'Answer mesh-cli: the control-node's operator is the terminal, everyone else is not (hq ADR 0272)' (#176) from feat/272-answer-mesh-cli into main

cmd/mesh-controller/acts.go

@@ -51,6 +51,9 @@ func assignWith(ctx context.Context, open *stores, node string, opts assignOptio
 	if len(modules) == 0 {
 		return "", fmt.Errorf("assign %s names no module", node)
 	}
+	if err := refusedMovingTheController(modules); err != nil {
+		return "", err
+	}
 	// Held while it is recorded, so it cannot land between a converge's preview and its flip and
 	// be taken without ever having been previewed (novox/hq ADR 0100).
 	ctx, release, err := holdNodes(ctx, open, []string{node})
@@ -209,6 +212,9 @@ func seatDependenciesOnAssign(ctx context.Context, open *stores, node string, mo
 // (novox/hq ADR 0207) — the other side of refusing that module's assignment without one. Several
 // modules in one act are judged together, so a holder and its dependents come off in one command.
 func unassign(ctx context.Context, open *stores, node string, modules ...string) (string, error) {
+	if err := refusedMovingTheController(modules); err != nil {
+		return "", err
+	}
 	if len(modules) == 0 {
 		return "", fmt.Errorf("unassign %s names no module", node)
 	}
@@ -360,3 +366,17 @@ func issueOnAssign(ctx context.Context, open *stores, node, module string) strin
 	}
 	return fmt.Sprintf("its bus credential is issued and sealed to %s, and arrives with the push", node)
 }
+
+// refusedMovingTheController refuses assigning or unassigning the controller's module through a verb (review of
+// novox/hq ADR 0272): the node it is assigned to is the control-node, and the control-node's operator account is
+// the controller's terminal, so whoever moves the module chooses the terminal. At the terminal alone, as every
+// change that says who may change what.
+func refusedMovingTheController(modules []string) error {
+	verb, through := throughAVerb()
+	if !through || !slices.Contains(modules, controllerModule) {
+		return nil
+	}
+	return fmt.Errorf("%s is assigned and unassigned at the controller's terminal only (mesh-cli on the control-node), "+
+		"never through a verb (this came through %q): the node it runs on is the control-node, whose operator is the "+
+		"terminal (novox/hq ADR 0272). Nothing was assigned", controllerModule, verb)
+}

cmd/mesh-controller/build_source.go

@@ -47,10 +47,20 @@ const servedVar = "MESH_SERVED_BY_THE_CONTROLLER"
 // not anything it started, not a verb's command, not a seat call's. The serving controller marks its own
 // environment (servedVar), so a build asked in it, or by any process it starts, never reads as the terminal's;
 // runVerb also names the verb and the caller.
+//
+// **And a line mesh-cli asked as the controller's terminal** (novox/hq ADR 0272 §4): the serving controller runs it
+// without the served mark and without a verb, names its caller, and marks it with cliTerminalVar — a mark only the
+// mesh-cli path sets and every other command line the controller runs is stripped of (commandEnvironment).
 func startedAtTheTerminal() bool {
-	return os.Getenv(servedVar) == "" && os.Getenv(verbVar) == "" && os.Getenv(link.CallerVar) == ""
+	if os.Getenv(servedVar) != "" || os.Getenv(verbVar) != "" {
+		return false
+	}
+	return os.Getenv(link.CallerVar) == "" || os.Getenv(cliTerminalVar) != ""
 }
 
+// cliTerminalVar marks a command line the serving controller runs as the controller's terminal for mesh-cli.
+const cliTerminalVar = "MESH_CLI_TERMINAL"
+
 // markServed marks this process, and so everything it starts, as the serving controller's.
 func markServed() {
 	if err := os.Setenv(servedVar, "1"); err != nil {

cmd/mesh-controller/main.go

@@ -216,6 +216,10 @@ func run() error {
 func usage() {
 	fmt.Fprint(os.Stderr, `mesh-controller — the control plane
 
+  On a node the operator types these as 'mesh-cli <command>' (in zsh, 'nox <command>'): asked
+  through the node's engine, and run as the controller's terminal only on the control-node
+  (novox/hq ADR 0272).
+
   migrate                        bring each context's schema up to date
   prepare                        the same, asked the way the mesh asks any module (ADR 0135)
   node add <name> [--adopted]    create a node record; --adopted: the machine is in use

cmd/mesh-controller/meshcli.go

@@ -0,0 +1,255 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"os/exec"
+	"slices"
+	"strings"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The operator's command, `mesh-cli` (alias `nox`), answered here (novox/hq ADR 0272).
+//
+// mesh-cli asks the node-engine on its own machine; the engine reads the asking account from the kernel and asks
+// this controller on its own node's subject. Here it is judged — the controller's terminal, an ordinary call, or
+// nothing — and run as every verb's line is: a fresh process of this binary, with this process's environment.
+//
+// **The terminal** is a line from a node's operator account, on the control-node (§4). Phase 2 adds a node whose
+// agents run under an account of their own, judged unable to become root (ADR 0266, not built yet); until then no
+// other node is the terminal, because agents there run as its operator. **An ordinary call** is a line from that
+// account elsewhere: it meets every refusal of the generic `command` verb and runs with `MESH_VERB=mesh-cli`, so a
+// terminal-only change is refused with its reason. **Any other account is refused**, root included: those two
+// accounts already reach the mesh's verbs through the mesh MCP server, and no other account gains anything here.
+
+// cliVerb is what a line from mesh-cli that is not the terminal runs as: the verb its process names, so every
+// terminal-only refusal applies and says it came through mesh-cli.
+const cliVerb = "mesh-cli"
+
+// cliServers are commands that serve until stopped. Run for mesh-cli they would hold a second server under this
+// one until the call's bound killed it.
+var cliServers = map[string]bool{"serve": true, "api": true, "board": true}
+
+// cliVerdict is how a line is run, or why it is not.
+type cliVerdict struct {
+	terminal bool
+	// why says why the line is or is not the terminal, in words the operator reads under the answer.
+	why string
+	// refused says why nothing runs.
+	refused string
+}
+
+// judgeCLI decides how a line from mesh-cli runs (ADR 0272 §4). nodes is every node the mesh knows; control is
+// every node the controller's module is assigned to, which is exactly one in a mesh that is well.
+func judgeCLI(node string, asked link.CLIAsked, nodes []inventory.Node, control []string) cliVerdict {
+	var record *inventory.Node
+	for i := range nodes {
+		if nodes[i].Name == node {
+			record = &nodes[i]
+			break
+		}
+	}
+	switch {
+	case record == nil:
+		return cliVerdict{refused: fmt.Sprintf("%s is not a node this mesh knows, so nothing ran", node)}
+	case asked.UID == 0 || asked.Account == "root":
+		return cliVerdict{refused: "mesh-cli answers the operator's own account, never root: run it as yourself, " +
+			"not under sudo. Nothing ran"}
+	case record.Account == "":
+		return cliVerdict{refused: fmt.Sprintf("the mesh does not know %s's operator account (`node account <node> <login>`), "+
+			"so no account there is answered. Nothing ran", node)}
+	case asked.Account != record.Account:
+		return cliVerdict{refused: fmt.Sprintf("mesh-cli answers %s's operator account (%s) only, and this line came "+
+			"from %s. Nothing ran", node, record.Account, asked.Account)}
+	}
+	if len(control) != 1 {
+		return cliVerdict{why: fmt.Sprintf("not the controller's terminal: the mesh names %d control-nodes, and the "+
+			"terminal is the one control-node's operator account", len(control))}
+	}
+	if control[0] == node {
+		return cliVerdict{terminal: true, why: fmt.Sprintf("the controller's terminal: %s on the control-node %s",
+			asked.Account, node)}
+	}
+	return cliVerdict{why: fmt.Sprintf("not the controller's terminal: agents on %s may run as %s, so a "+
+		"terminal-only change is made from the control-node %s (novox/hq ADR 0272)", node, asked.Account, control[0])}
+}
+
+// controlNodes is every node the controller's module is assigned to.
+func controlNodes(ctx context.Context, inv *inventory.Inventory, nodes []inventory.Node) ([]string, error) {
+	var out []string
+	for _, n := range nodes {
+		modules, err := inv.Assigned(ctx, n.Name)
+		if err != nil {
+			return nil, err
+		}
+		if slices.Contains(modules, controllerModule) {
+			out = append(out, n.Name)
+		}
+	}
+	return out, nil
+}
+
+// controllerModule is the module that runs the controller, and so marks the control-node.
+const controllerModule = "mesh-controller"
+
+// answerMeshCLI is the serving controller's answer to mesh-cli.
+func answerMeshCLI(inv *inventory.Inventory) link.CLIHandler {
+	return func(ctx context.Context, node string, asked link.CLIAsked) link.CLIAnswer {
+		if handingOver.Load() {
+			return link.CLIRefusal("this controller is stopping and runs no new command; ask again in a moment. Nothing ran")
+		}
+		nodes, err := inv.Nodes(ctx)
+		if err != nil {
+			return link.CLIRefusal("the mesh's nodes cannot be read, so nothing ran: " + err.Error())
+		}
+		control, err := controlNodes(ctx, inv, nodes)
+		if err != nil {
+			return link.CLIRefusal("which node is the control-node cannot be read, so nothing ran: " + err.Error())
+		}
+		return runForMeshCLI(ctx, node, asked, judgeCLI(node, asked, nodes, control))
+	}
+}
+
+// cliJournal says one line in the controller's journal (its standard output); a variable so a test can read it.
+var cliJournal = func(line string) { fmt.Println(line) }
+
+// runForMeshCLI runs a judged line and answers what it said. Every line is said in the journal first: its call,
+// who asked on which node, its command word only, and how it runs (review of ADR 0272).
+func runForMeshCLI(ctx context.Context, node string, asked link.CLIAsked, v cliVerdict) link.CLIAnswer {
+	how := "as an ordinary call"
+	switch {
+	case v.refused != "":
+		how = "refused: " + v.refused
+	case v.terminal:
+		how = "as the controller's terminal"
+	}
+	call := link.CallIDIn(ctx)
+	if call == "" {
+		call = "(no call)"
+	}
+	cliJournal(fmt.Sprintf("mesh-cli %s: %s on %s asked %q, %s", call, asked.Account, node, asked.Line[0], how))
+	if v.refused != "" {
+		return link.CLIRefusal(v.refused)
+	}
+	if cliServers[asked.Line[0]] {
+		return link.CLIAnswer{Exit: 1, Why: v.why, Refused: fmt.Sprintf("%s serves until stopped, and is not a "+
+			"command line mesh-cli runs. Nothing ran", asked.Line[0])}
+	}
+	verb, line := "", asked.Line
+	if !v.terminal {
+		composed, err := ordinaryLine(asked.Line)
+		if err != nil {
+			return link.CLIAnswer{Exit: 1, Why: v.why, Refused: err.Error()}
+		}
+		verb, line = cliVerb, composed
+	}
+	cmd := selfCommand(ctx, line)
+	cmd.Env = commandEnvironment(fmt.Sprintf("%s through mesh-cli on %s", asked.Account, node), verb)
+	// No standard input: a command that reads one gets nothing, and fails saying so (ADR 0272 §5).
+	cmd.Stdin = nil
+	var stdout, stderr bytes.Buffer
+	cmd.Stdout, cmd.Stderr = &stdout, &stderr
+	err := cmd.Run()
+	answer := link.CLIAnswer{Stdout: stdout.Bytes(), Stderr: stderr.Bytes(), Terminal: v.terminal, Why: v.why}
+	var exit *exec.ExitError
+	switch {
+	case err == nil:
+	case errors.As(err, &exit):
+		answer.Exit = exit.ExitCode()
+		if answer.Exit < 0 {
+			// Killed: by the call's bound, or by this controller stopping.
+			answer.Exit = 1
+			answer.Stderr = append(answer.Stderr, []byte(fmt.Sprintf("\nmesh-cli: the command was stopped (%v)\n",
+				exit))...)
+		}
+	default:
+		answer.Exit = 1
+		answer.Refused = fmt.Sprintf("could not run %s from this controller's own build: %v", strings.Join(asked.Line, " "), err)
+	}
+	return answer
+}
+
+// settingsForms is what an ordinary `settings` line may say: the settings verb's own forms.
+const settingsForms = "settings set <module> <values> [--replace] [--node <node>], settings clear <module> " +
+	"[--node <node>], settings show <module> [--history] [--node <node>], or settings preferences [<module>] " +
+	"[--node <node>]"
+
+// ordinaryLine is the command line an ordinary call runs (ADR 0272 §4): a `settings` line composed exactly as the
+// settings verb composes its own, so its refusals — the terminal-only keys among them — are that verb's (review of
+// ADR 0272); any other line as the generic `command` verb takes it, with its refusals.
+func ordinaryLine(argv []string) ([]string, error) {
+	if len(argv) == 0 || argv[0] != "settings" {
+		// What the generic verb runs, and nothing it would refuse: its reading forms only, and never a command that
+		// is the terminal's alone (novox/hq ADR 0266) — the two checks argvFor makes of the `command` verb's line,
+		// made of the words as given rather than re-split from one string.
+		if err := refusedAsTheGenericCommand(argv); err != nil {
+			return nil, err
+		}
+		if err := terminalOnly(argv); err != nil {
+			return nil, err
+		}
+		return argv, nil
+	}
+	args := map[string]any{}
+	var words []string
+	rest := argv[1:]
+	for i := 0; i < len(rest); i++ {
+		w := rest[i]
+		switch {
+		case w == "--replace" || w == "-replace":
+			args["replace"] = "true"
+		case w == "--history" || w == "-history":
+			args["history"] = "true"
+		case w == "--node" || w == "-node":
+			if i+1 >= len(rest) {
+				return nil, fmt.Errorf("--node names no node; settings takes %s. Nothing ran", settingsForms)
+			}
+			i++
+			args["node"] = rest[i]
+		case strings.HasPrefix(w, "--node=") || strings.HasPrefix(w, "-node="):
+			_, args["node"], _ = strings.Cut(w, "=")
+		case strings.HasPrefix(w, "-"):
+			return nil, fmt.Errorf("settings takes no %s through mesh-cli outside the terminal; it takes %s. "+
+				"Nothing ran", w, settingsForms)
+		default:
+			words = append(words, w)
+		}
+	}
+	wrong := fmt.Errorf("through mesh-cli outside the terminal, settings takes the settings verb's forms: %s. "+
+		"Nothing ran", settingsForms)
+	if len(words) == 0 {
+		return nil, wrong
+	}
+	switch words[0] {
+	case "set":
+		if len(words) != 3 {
+			return nil, wrong
+		}
+		args["module"], args["values"] = words[1], words[2]
+	case "clear":
+		if len(words) != 2 {
+			return nil, wrong
+		}
+		args["module"], args["clear"] = words[1], "true"
+	case "show":
+		if len(words) != 2 {
+			return nil, wrong
+		}
+		args["module"] = words[1]
+	case "preferences":
+		if len(words) > 2 {
+			return nil, wrong
+		}
+		args["list"] = "preferences"
+		if len(words) == 2 {
+			args["module"] = words[1]
+		}
+	default:
+		return nil, wrong
+	}
+	return argvFor("settings", args)
+}

cmd/mesh-controller/meshcli_test.go

@@ -0,0 +1,266 @@
+package main
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+// echoEnvironment makes the test binary, run as a command line, say the verb and caller it was given (TestMain).
+const echoEnvironment = "MESH_TEST_ECHO_ENVIRONMENT"
+
+var cliNodes = []inventory.Node{
+	{Name: "control", Account: "operator"},
+	{Name: "laptop", Account: "operator"},
+	{Name: "unnamed"},
+}
+
+func asked(account string, uid uint32, line ...string) link.CLIAsked {
+	return link.CLIAsked{Line: line, Account: account, UID: uid}
+}
+
+// Who is the controller's terminal, and who is an ordinary call or refused (novox/hq ADR 0272 §4).
+func TestMeshCLIIsTheTerminalOnlyForTheControlNodesOperator(t *testing.T) {
+	control := []string{"control"}
+	cases := []struct {
+		name, node string
+		asked      link.CLIAsked
+		control    []string
+		terminal   bool
+		refused    string
+		why        string
+	}{
+		{"the control-node's operator", "control", asked("operator", 1000, "status"), control, true, "", "the controller's terminal"},
+		{"another node's operator", "laptop", asked("operator", 1000, "status"), control, false, "", "agents on laptop may run as operator"},
+		{"another account", "control", asked("agent", 1001, "status"), control, false, "operator account (operator) only", ""},
+		{"root", "control", asked("root", 0, "status"), control, false, "never root", ""},
+		{"a node with no operator account", "unnamed", asked("operator", 1000, "status"), control, false, "does not know unnamed's operator account", ""},
+		{"a node the mesh does not know", "elsewhere", asked("operator", 1000, "status"), control, false, "not a node this mesh knows", ""},
+		{"two control-nodes", "control", asked("operator", 1000, "status"), []string{"control", "laptop"}, false, "", "2 control-nodes"},
+	}
+	for _, c := range cases {
+		v := judgeCLI(c.node, c.asked, cliNodes, c.control)
+		if v.terminal != c.terminal {
+			t.Errorf("%s: terminal %v, want %v (%+v)", c.name, v.terminal, c.terminal, v)
+		}
+		if c.refused == "" && v.refused != "" || c.refused != "" && !strings.Contains(v.refused, c.refused) {
+			t.Errorf("%s: refused %q, want %q", c.name, v.refused, c.refused)
+		}
+		if c.why != "" && !strings.Contains(v.why, c.why) {
+			t.Errorf("%s: why %q, want %q", c.name, v.why, c.why)
+		}
+	}
+}
+
+// The terminal runs its line without MESH_VERB, even where this process carries one; an ordinary call names
+// mesh-cli; both record who asked through mesh-cli.
+func TestTheTerminalRunsWithoutAVerbAndAnOrdinaryCallNamesMeshCLI(t *testing.T) {
+	t.Setenv(echoEnvironment, "1")
+	t.Setenv("MESH_VERB", "leaked-from-the-serving-process")
+	// The serving controller marks itself (ADR 0266); its terminal line for mesh-cli is still the terminal's.
+	t.Setenv(servedVar, "1")
+	ctx := context.Background()
+
+	a := runForMeshCLI(ctx, "control", asked("operator", 1000, "status"), cliVerdict{terminal: true, why: "the terminal"})
+	if a.Exit != 0 || a.Refused != "" || !a.Terminal {
+		t.Fatalf("the terminal's line did not run: %+v", a)
+	}
+	if got := string(a.Stdout); !strings.Contains(got, `verb=""`) || !strings.Contains(got, "operator through mesh-cli on control") ||
+		!strings.Contains(got, "terminal=true") {
+		t.Fatalf("the terminal's line ran with %s", got)
+	}
+
+	a = runForMeshCLI(ctx, "laptop", asked("operator", 1000, "status"), cliVerdict{why: "not the terminal"})
+	if a.Exit != 0 || a.Terminal || a.Why != "not the terminal" {
+		t.Fatalf("an ordinary line did not run as one: %+v", a)
+	}
+	if got := string(a.Stdout); !strings.Contains(got, `verb="mesh-cli"`) || !strings.Contains(got, "terminal=false") {
+		t.Fatalf("an ordinary line ran with %s", got)
+	}
+}
+
+// An ordinary call meets every refusal of the generic command verb, and nothing runs; a server is never run.
+func TestAnOrdinaryCallMeetsTheCommandVerbsRefusals(t *testing.T) {
+	t.Setenv(echoEnvironment, "1")
+	ctx := context.Background()
+	ordinary := cliVerdict{why: "not the terminal"}
+	a := runForMeshCLI(ctx, "laptop", asked("operator", 1000, "cleanup", "delete", "x"), ordinary)
+	if a.Refused == "" || len(a.Stdout) != 0 || a.Exit != 1 || a.Why != "not the terminal" {
+		t.Fatalf("a repair without --why ran as an ordinary call: %+v", a)
+	}
+	a = runForMeshCLI(ctx, "laptop", asked("operator", 1000, "settings", "set", "claude-code", "{}"), ordinary)
+	if a.Refused != "" || !strings.Contains(string(a.Stdout), `verb="mesh-cli"`) {
+		t.Fatalf("an ordinary settings set did not run through the settings verb's path with MESH_VERB set: %+v", a)
+	}
+	for _, server := range []string{"serve", "api", "board"} {
+		a := runForMeshCLI(ctx, "control", asked("operator", 1000, server), cliVerdict{terminal: true})
+		if a.Refused == "" || len(a.Stdout) != 0 {
+			t.Fatalf("%s was run for mesh-cli: %+v", server, a)
+		}
+	}
+	a = runForMeshCLI(ctx, "control", asked("agent", 1001, "status"), cliVerdict{refused: "agent is not answered"})
+	if a.Refused != "agent is not answered" || len(a.Stdout) != 0 {
+		t.Fatalf("a refused line ran: %+v", a)
+	}
+}
+
+// **Which node is the terminal does not follow a verb** (review of ADR 0272): the controller's module is assigned
+// and unassigned at the terminal alone, so no caller of `assign` can move the terminal to a node of its choosing.
+// Asked through the acts themselves, as the verbs ask them; refused before any store is touched (none is given).
+func TestTheControllersModuleIsMovedAtTheTerminalAlone(t *testing.T) {
+	t.Setenv("MESH_VERB", "assign")
+	ctx := context.Background()
+	if _, err := assignWith(ctx, nil, "laptop", assignOptions{}, "zsh", "mesh-controller"); err == nil ||
+		!strings.Contains(err.Error(), "terminal") {
+		t.Fatalf("assigning the controller through a verb was not refused: %v", err)
+	}
+	if _, err := assign(ctx, nil, "laptop", "mesh-controller"); err == nil || !strings.Contains(err.Error(), "terminal") {
+		t.Fatalf("assigning the controller through a verb was not refused: %v", err)
+	}
+	t.Setenv("MESH_VERB", "unassign")
+	if _, err := unassign(ctx, nil, "control", "mesh-controller"); err == nil || !strings.Contains(err.Error(), "terminal") {
+		t.Fatalf("unassigning the controller through a verb was not refused: %v", err)
+	}
+	// Another module through a verb, and the controller's at the terminal, are not refused for it.
+	if err := refusedMovingTheController([]string{"zsh"}); err != nil {
+		t.Fatalf("another module was refused: %v", err)
+	}
+	t.Setenv("MESH_VERB", "")
+	if err := refusedMovingTheController([]string{"mesh-controller"}); err != nil {
+		t.Fatalf("the terminal was refused: %v", err)
+	}
+}
+
+// An ordinary `settings set|clear` goes down the settings verb's own path: composed as that verb composes it, and
+// run with MESH_VERB set, so its refusals — the terminal-only keys among them — are the settings command's own,
+// not a blanket refusal of the generic command (review of ADR 0272).
+func TestAnOrdinarySettingsLineTakesTheSettingsVerbsPath(t *testing.T) {
+	cases := []struct {
+		line []string
+		want string
+		err  string
+	}{
+		{[]string{"settings", "set", "zsh", `{"execute":"withhold"}`, "--node", "laptop"}, `settings set zsh {"execute":"withhold"} --node laptop`, ""},
+		{[]string{"settings", "set", "zsh", "{}", "--replace"}, "settings set zsh {} --replace", ""},
+		{[]string{"settings", "clear", "zsh", "--node", "laptop"}, "settings clear zsh --node laptop", ""},
+		{[]string{"settings", "show", "zsh", "--history"}, "settings show zsh --history", ""},
+		{[]string{"settings", "preferences"}, "settings preferences", ""},
+		{[]string{"settings", "set", "zsh"}, "", "settings"},
+		{[]string{"settings", "set", "zsh", "{}", "--sideways"}, "", "--sideways"},
+	}
+	for _, c := range cases {
+		argv, err := ordinaryLine(c.line)
+		if c.err != "" {
+			if err == nil || !strings.Contains(err.Error(), c.err) {
+				t.Errorf("%q: refused with %v, want %q", c.line, err, c.err)
+			}
+			continue
+		}
+		if err != nil || strings.Join(argv, " ") != c.want {
+			t.Errorf("%q: composed %q (%v), want %q", c.line, argv, err, c.want)
+		}
+	}
+	// Anything else still meets the generic command verb's refusals.
+	if _, err := ordinaryLine([]string{"retire", "delete", "x"}); err == nil {
+		t.Error("a repair composed as an ordinary line")
+	}
+}
+
+// Every line is said in the controller's journal, with its call, who asked where and how it ran — its command word
+// only, never the rest of the line (review of ADR 0272).
+func TestEveryMeshCLILineIsSaidInTheJournal(t *testing.T) {
+	t.Setenv(echoEnvironment, "1")
+	var said []string
+	was := cliJournal
+	cliJournal = func(line string) { said = append(said, line) }
+	t.Cleanup(func() { cliJournal = was })
+	ctx := link.WithCallID(context.Background(), "call-1")
+	runForMeshCLI(ctx, "control", asked("operator", 1000, "settings", "set", "x", `{"password":"s3cret"}`),
+		cliVerdict{terminal: true, why: "the terminal"})
+	runForMeshCLI(ctx, "control", asked("agent", 1001, "status"), cliVerdict{refused: "agent is not answered"})
+	all := strings.Join(said, "\n")
+	if len(said) != 2 || !strings.Contains(all, "call-1") || !strings.Contains(all, "operator on control") ||
+		!strings.Contains(all, "as the controller's terminal") || !strings.Contains(all, "refused") {
+		t.Fatalf("the journal said %q", said)
+	}
+	if strings.Contains(all, "s3cret") {
+		t.Fatalf("the journal carries the line's values: %q", said)
+	}
+}
+
+// **An ordinary line runs only what the generic command verb would** (review of ADR 0272, ADR 0266): its reading
+// forms, and never a command that is the terminal's alone. Each of these, from another node's operator, is refused
+// and runs nothing.
+func TestAnOrdinaryLineRunsNothingTheCommandVerbWouldRefuse(t *testing.T) {
+	t.Setenv(echoEnvironment, "1")
+	for _, line := range [][]string{
+		{"node", "account", "control", "x"},
+		{"node", "agent-account", "control", "x", "--clear"},
+		{"token", "issue", "laptop"},
+		{"secret", "export", "x"},
+		{"operator", "key", "set", "x"},
+		{"assign", "laptop", "zsh"},
+	} {
+		if _, err := ordinaryLine(line); err == nil {
+			t.Errorf("%q composed as an ordinary line", line)
+		}
+		a := runForMeshCLI(context.Background(), "laptop", asked("operator", 1000, line...), cliVerdict{why: "not the terminal"})
+		if a.Refused == "" || len(a.Stdout) != 0 {
+			t.Errorf("%q ran as an ordinary line: %+v", line, a)
+		}
+	}
+	if argv, err := ordinaryLine([]string{"status"}); err != nil || argv[0] != "status" {
+		t.Fatalf("a read was refused: %v", err)
+	}
+}
+
+// **`calls` never shows a mesh-cli line's answer** (review of ADR 0272): the verb's own answer is read for a line
+// served over a bus, and neither the answer's text nor the base64 JSON writes its bytes in is there.
+func TestTheCallsVerbNeverShowsAMeshCLILinesAnswer(t *testing.T) {
+	conn, err := nats.Connect(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+	stop, err := link.OverNATS{Conn: conn}.ServeCLI(func(context.Context, string, link.CLIAsked) link.CLIAnswer {
+		return link.CLIAnswer{Stdout: []byte("s3cret-join")}
+	}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stop()
+	body, _ := json.Marshal(link.CLIAsked{Line: []string{"token", "issue", "x"}, Account: "operator"})
+	msg, err := conn.Request(link.CLISubject("control"), body, 5*time.Second)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(string(msg.Data), base64.StdEncoding.EncodeToString([]byte("s3cret-join"))) {
+		t.Fatalf("the asker was not given its answer: %s", msg.Data)
+	}
+	recent, _ := link.Calls.Recent()
+	var id string
+	for _, c := range recent {
+		if c.Seat == link.CLISeat {
+			id = c.ID
+			break
+		}
+	}
+	shown, err := callsAnswer(link.Calls, id)
+	if err != nil {
+		t.Fatal(err)
+	}
+	said, _ := json.Marshal(shown)
+	if strings.Contains(string(said), "s3cret-join") ||
+		strings.Contains(string(said), base64.StdEncoding.EncodeToString([]byte("s3cret-join"))) {
+		t.Fatalf("calls showed a mesh-cli line's answer: %s", said)
+	}
+}

cmd/mesh-controller/modules.go

@@ -1107,7 +1107,7 @@ func refuseTerminalSettingsThroughAVerb(ctx context.Context, inv *inventory.Inve
 	}
 	// A trusted mergeable file takes any key, so its module's whole layer is the terminal's (novox/hq issue 340).
 	if files := catalogue.TrustedMergeable(shelf[module]); len(files) > 0 && !sameLayer(before, after) {
-		return fmt.Errorf("the settings of %s on %s are set at the controller's terminal only, never through a verb (this "+
+		return fmt.Errorf("the settings of %s on %s are set at the controller's terminal only (`mesh-cli` on the control-node), never through a verb (this "+
 			"line came through %q): %s merges whatever key a layer sets into a file root or a consumer trusts, so "+
 			"any key could point the module at a listener of the caller's, and whoever may call a verb includes "+
 			"agents (novox/hq issue 340; a file nothing trusts says \"trusted\": false). Nothing was changed",
@@ -1119,7 +1119,7 @@ func refuseTerminalSettingsThroughAVerb(ctx context.Context, inv *inventory.Inve
 		if string(was) == string(now) {
 			continue
 		}
-		return fmt.Errorf("%s of %s on %s is set at the controller's terminal only, never through a verb (this "+
+		return fmt.Errorf("%s of %s on %s is set at the controller's terminal only (`mesh-cli` on the control-node), never through a verb (this "+
 			"line came through %q): it says where root creates and owns a module's directories, which of "+
 			"the machine's paths are mounted into its container, what the mesh's consumers trust, or what a file "+
 			"root or a person's session obeys takes, and whoever may call a verb includes agents (novox/hq issue 339; "+

cmd/mesh-controller/push.go

@@ -266,6 +266,12 @@ func serve(ctx context.Context) (err error) {
 		return err
 	}
 	defer stopServing()
+	// And the operator's command on every node, asked through each node's engine (novox/hq ADR 0272).
+	stopCLI, err := bus.ServeCLI(answerMeshCLI(open.inventory), log.New(os.Stdout, "", log.LstdFlags))
+	if err != nil {
+		return err
+	}
+	defer stopCLI()
 	// And says so on the bus (novox/hq ADR 0197): what it serves, as the NATS services protocol asks.
 	stopAnnouncing, err := bus.Announce(seatAnnouncement(handlers), log.New(os.Stdout, "", log.LstdFlags))
 	if err != nil {

cmd/mesh-controller/sayable_test.go

@@ -26,6 +26,12 @@ import (
 // shape fails the suite, naming its source. The keeper would say such a summary in words at run time;
 // this is where the producer is made to say it rightly in the first place.
 func TestMain(m *testing.M) {
+	// The process a mesh-cli test runs as a command line: it says the verb and the caller it was given, and
+	// ends (meshcli_test.go).
+	if os.Getenv(echoEnvironment) != "" {
+		fmt.Printf("verb=%q caller=%q terminal=%v\n", os.Getenv("MESH_VERB"), os.Getenv("MESH_CALLER"), startedAtTheTerminal())
+		os.Exit(0)
+	}
 	conditions.Unsayable = func(o conditions.Observation, field string, r outward.Refusal) {
 		unsaid.note(o, field, r)
 	}

cmd/mesh-controller/seatverbs.go

@@ -229,6 +229,35 @@ func quoteAll(xs []string) string {
 	return strings.Join(q, ", ")
 }
 
+// refusedAsTheGenericCommand is what the generic `command` verb refuses of a command line, and so what every
+// line asked through a verb's route refuses: the `command` verb's, and an ordinary line from mesh-cli (novox/hq ADR
+// 0272 §4). One function, so the two routes cannot drift apart.
+func refusedAsTheGenericCommand(argv []string) error {
+	if len(argv) == 0 {
+		return errors.New("command names no command")
+	}
+	// A layer is written through the settings verb, never the generic one (novox/hq issue 339): the
+	// settings verb is where what a verb may not set is refused, and one route is one set of words.
+	// The command refuses places and accesses through any verb as well; this says so before it runs.
+	if argv[0] == "settings" && slices.ContainsFunc(argv[1:], func(w string) bool { return w == "set" || w == "clear" }) {
+		return &heldAtTheTerminal{msg: "settings are set and cleared through the settings verb, not the " +
+			"generic command; and places and accesses only at the controller's terminal (novox/hq issue 339). " +
+			"Nothing was done"}
+	}
+	// The generic verb only reads (novox/hq ADR 0266): what writes has a named verb that composes its own
+	// line, or is the operator's at the controller's terminal.
+	if err := commandReads(argv); err != nil {
+		return err
+	}
+	// The generic verb is no way round the hand-act log (novox/hq to-be 45 §7): a repair through
+	// it says why, as it would through its own verb.
+	if repair := repairingCommand(argv); repair != "" && !slices.ContainsFunc(argv, isWhyFlag) {
+		return fmt.Errorf("%s is a repair done by hand, and says why: add --why <text> to the command "+
+			"line (recorded in the hand-act log). Nothing was done", repair)
+	}
+	return nil
+}
+
 // commandLine composes the command. Every argument it reads is one it uses: a branch that reads an
 // argument and then drops it would pass it over, which is what the check after it exists to refuse.
 func (a *verbArguments) commandLine() ([]string, error) {
@@ -245,28 +274,9 @@ func (a *verbArguments) commandLine() ([]string, error) {
 		if err != nil {
 			return nil, err
 		}
-		if len(argv) == 0 {
-			return nil, errors.New("command names no command")
-		}
-		// A layer is written through the settings verb, never the generic one (novox/hq issue 339): the
-		// settings verb is where what a verb may not set is refused, and one route is one set of words.
-		// The command refuses places and accesses through any verb as well; this says so before it runs.
-		if argv[0] == "settings" && slices.ContainsFunc(argv[1:], func(w string) bool { return w == "set" || w == "clear" }) {
-			return nil, &heldAtTheTerminal{msg: "settings are set and cleared through the settings verb, not the " +
-				"generic command; and places and accesses only at the controller's terminal (novox/hq issue 339). " +
-				"Nothing was done"}
-		}
-		// The generic verb only reads (novox/hq ADR 0266): what writes has a named verb that composes its own
-		// line, or is the operator's at the controller's terminal.
-		if err := commandReads(argv); err != nil {
+		if err := refusedAsTheGenericCommand(argv); err != nil {
 			return nil, err
 		}
-		// The generic verb is no way round the hand-act log (novox/hq to-be 45 §7): a repair through
-		// it says why, as it would through its own verb.
-		if repair := repairingCommand(argv); repair != "" && !slices.ContainsFunc(argv, isWhyFlag) {
-			return nil, fmt.Errorf("%s is a repair done by hand, and says why: add --why <text> to the command "+
-				"line (recorded in the hand-act log). Nothing was done", repair)
-		}
 		return argv, nil
 	case "tools":
 		return nil, errors.New("tools is answered from the records, not by a command")
@@ -919,6 +929,31 @@ func isWhyFlag(word string) bool {
 	return word == "--why" || word == "-why" || strings.HasPrefix(word, "--why=") || strings.HasPrefix(word, "-why=")
 }
 
+// commandEnvironment is the environment of a command line this controller runs for someone: its own — the
+// stores' credentials, the bus, the broker, everything a command run from a shell beside it would have, because it
+// is that — with who asked, and the verb it came through. An empty verb is the controller's terminal (novox/hq ADR
+// 0272 §4): no `MESH_VERB` at all, whatever this process was started with.
+//
+// The terminal's line is also not the serving controller's (servedVar), and carries cliTerminalVar, so what reads
+// whether it was started at the terminal (startedAtTheTerminal) reads yes; every other line is stripped of that mark.
+func commandEnvironment(caller, verb string) []string {
+	env := make([]string, 0, len(os.Environ())+3)
+	for _, kv := range os.Environ() {
+		if strings.HasPrefix(kv, verbVar+"=") || strings.HasPrefix(kv, link.CallerVar+"=") ||
+			strings.HasPrefix(kv, cliTerminalVar+"=") || (verb == "" && strings.HasPrefix(kv, servedVar+"=")) {
+			continue
+		}
+		env = append(env, kv)
+	}
+	env = append(env, link.CallerVar+"="+caller)
+	if verb != "" {
+		env = append(env, verbVar+"="+verb)
+	} else {
+		env = append(env, cliTerminalVar+"=1")
+	}
+	return env
+}
+
 // runVerb runs this binary with the given command line and gathers what it said.
 //
 // **This binary is the image this process runs, never the file at the path it started from**
@@ -932,21 +967,17 @@ func runVerb(ctx context.Context, argv []string) (verbAnswer, error) {
 		return verbAnswer{}, fmt.Errorf("%w: this controller is stopping and runs no new command", link.ErrHandingOver)
 	}
 	cmd := selfCommand(ctx, argv)
-	// The same environment: the stores' credentials, the bus, the broker — everything a command run
-	// from a shell in this container would have, because it is that.
-	cmd.Env = os.Environ()
 	// And who asked, so an act it does by hand is recorded as theirs (novox/hq to-be 45 §7).
 	caller := link.CallerIn(ctx)
 	if caller == "" {
 		caller = "a seat call whose caller the bus did not name"
 	}
-	cmd.Env = append(cmd.Env, link.CallerVar+"="+caller+", through the "+catalogue.ControllerSeatName+" seat")
 	// And which verb, so the connection it dials says so in the bus's list (novox/hq issue 327).
 	verb, _ := ctx.Value(verbKey{}).(string)
 	if verb == "" {
 		verb = argv[0]
 	}
-	cmd.Env = append(cmd.Env, verbVar+"="+verb)
+	cmd.Env = commandEnvironment(caller+", through the "+catalogue.ControllerSeatName+" seat", verb)
 	// Two buffers, one answer. What the command *says* is both streams, in the order a person at
 	// a shell would read them; what it *answers as data* is standard output alone — `status --json`
 	// prints its warnings beside the document, and a JSON parsed from the two together parsed
@@ -1168,7 +1199,7 @@ func answersFirst(argv []string) bool {
 // the reason said beside it.
 func callsAnswer(log *link.CallLog, id string) (any, error) {
 	if id != "" {
-		c, ok, err := log.Get(id)
+		c, ok, err := log.Shown(id)
 		if err != nil {
 			return nil, fmt.Errorf("call %s is not in this controller's memory, and the calls kept on the "+
 				"bus could not be read: %w", id, err)