feat(cli): add scope flag completion for mcp install

docs/usage.md

@@ -4,6 +4,20 @@
 
 The examples assume `jevwise` is installed on PATH. For a source build, use `bin/jevwise` instead.
 
+## Shell completion
+
+Enable completion in your current Zsh session (after installing/upgrading Jevwise):
+
+```sh
+autoload -Uz compinit
+compinit
+source <(jevwise completion zsh)
+```
+
+- For Bash, use `source <(jevwise completion bash)` instead. Fish and PowerShell scripts are available through `jevwise completion fish` and `jevwise completion powershell`.
+- `jevwise mcp install claude --scope <Tab>` suggests `user`, `local`, `project`; Codex suggests only `user`. Prefixes and `--scope=prefix` also work, without filename suggestions.
+- Completion reads no decision configuration or credentials and never invokes a client installer. Use a binary containing the new completion callback; source/worktree changes do not update an installed binary automatically.
+
 ## Decisions
 
 ```sh

internal/cli/mcp_completion_test.go

@@ -0,0 +1,40 @@
+package cli
+
+import (
+	"context"
+	"strings"
+	"testing"
+)
+
+func TestMCPInstallScopeCompletionIsClientSpecificAndLazy(t *testing.T) {
+	decisionEnvironment(t)
+	for _, tt := range []struct {
+		args []string
+		want string
+	}{
+		{[]string{"mcp", "install", "claude", "--scope", ""}, "user\nlocal\nproject\n:4\n"},
+		{[]string{"mcp", "install", "codex", "--scope", ""}, "user\n:4\n"},
+		{[]string{"mcp", "install", "--scope", ""}, "user\nlocal\nproject\n:4\n"},
+		{[]string{"mcp", "install", "claude", "--scope", "l"}, "local\n:4\n"},
+		{[]string{"mcp", "install", "claude", "--scope=pr"}, "project\n:4\n"},
+		{[]string{"mcp", "install", "codex", "--scope=u"}, "user\n:4\n"},
+		{[]string{"mcp", "install", "codex", "--scope", "l"}, ":4\n"},
+		{[]string{"mcp", "install", "claude", "--scope", "private-prefix"}, ":4\n"},
+	} {
+		for _, hidden := range []string{"__complete", "__completeNoDesc"} {
+			root := installerRoot(t, func(context.Context, string, ...string) ([]byte, error) {
+				t.Fatal("completion invoked a client")
+				return nil, nil
+			})
+			// Completion must remain available with unusable runtime settings.
+			args := []string{hidden, "--debug", "--config", "/missing", "--timeout", "invalid", "--api-key", "private-key"}
+			out, stderr, err := execute(root, append(args, tt.args...)...)
+			if err != nil || out != tt.want || !strings.Contains(stderr, "ShellCompDirectiveNoFileComp") {
+				t.Fatal("scope completion candidates or no-file directive changed", tt.args, err)
+			}
+			if strings.Contains(stderr, "mcp.install.register") || strings.Contains(out+stderr, "private") {
+				t.Fatal("completion ran installation or exposed input")
+			}
+		}
+	}
+}

internal/cli/mcp_install.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"io"
+	"strings"
 	"time"
 
 	"github.com/bitbrew-dev/jevwise/internal/debuglog"
@@ -24,6 +25,19 @@ func newMCPInstall(run agentCommand) *cobra.Command {
 		RunE: func(cmd *cobra.Command, _ []string) error { return cmd.Help() }}
 	cmd.PersistentFlags().StringVar(&address, "listen", "127.0.0.1:8080", "Server's literal loopback IP:port (same as mcp --listen)")
 	cmd.PersistentFlags().StringVar(&scope, "scope", "user", "Client settings scope: user; Claude also supports local or project")
+	_ = cmd.RegisterFlagCompletionFunc("scope", func(cmd *cobra.Command, _ []string, prefix string) ([]string, cobra.ShellCompDirective) {
+		choices := []string{"user"}
+		if cmd.Name() != "codex" {
+			choices = append(choices, "local", "project")
+		}
+		var matches []string
+		for _, choice := range choices {
+			if strings.HasPrefix(choice, prefix) {
+				matches = append(matches, choice)
+			}
+		}
+		return matches, cobra.ShellCompDirectiveNoFileComp
+	})
 	for _, client := range []string{"codex", "claude"} {
 		cmd.AddCommand(&cobra.Command{Use: client, Short: "Register Jevwise with " + client, Args: noArgs,
 			RunE: func(cmd *cobra.Command, _ []string) error {