fix: direct-slash resume-safe commands route to CliAction instead of interactive_only (#831)

`claw /status`, `claw /diff`, `claw /version`, `claw /doctor`,
`claw /sandbox` all returned interactive_only because the direct-slash
handler only had explicit arms for /help, /agents, /mcp, /skills.
Other resume-safe slash commands fell through to the generic
`Ok(Some(command)) => Err(interactive_only...)` arm.

Fix: add explicit routing arms for SlashCommand::Status, ::Diff,
::Version, ::Doctor, ::Sandbox in `parse_direct_slash_command`.

One new integration test: direct_slash_resume_safe_commands_route_correctly
(covers /version, /sandbox, /diff)

572+ tests pass.

ROADMAP.md

@@ -7906,3 +7906,9 @@ Original filing (2026-04-18): the session emitted `SessionStart hook (completed)
     **Required fix shape.** The MCP subcommand parser should detect `show` with no following token and emit `missing_argument: mcp show requires a server name.\nUsage: claw mcp show <server>` with a distinct `error_kind`. Update the classifier arm to return `missing_argument` for this prefix.
 
     **Acceptance.** `claw --output-format json mcp show` exits rc=1, stdout `error_kind:"missing_argument"`, stderr empty. Hint contains usage example. [SCOPE: claw-code]
+
+831. **Direct-slash resume-safe commands (`claw /status`, `claw /diff`, `claw /version`, `claw /doctor`, `claw /sandbox`) return `interactive_only` instead of executing** — dogfooded 2026-05-29 17:05 on `main` `ac5b19de`. `/help`, `/agents`, `/skills list` work because they have explicit `CliAction` routing arms in `parse_direct_slash_command`. `/status`, `/diff`, `/version`, `/doctor`, `/sandbox` fall through to the generic `Ok(Some(command)) => Err(interactive_only...)` arm. The hint correctly suggests `--resume SESSION.jsonl /status`, but `claw /status` directly should also work — these commands don't need a session.
+
+    **Required fix shape.** Add explicit `Ok(Some(SlashCommand::Status | Diff | Version | Doctor | Sandbox))` arms in `parse_direct_slash_command` routing to the same `CliAction` variants as `"status"` / `"diff"` / `"version"` / `"doctor"` / `"sandbox"` subcommands.
+
+    **Acceptance.** `claw --output-format json /status` exits 0 and emits the same envelope as `claw --output-format json status`. [SCOPE: claw-code]

rust/crates/commands/src/lib.rs

@@ -3027,7 +3027,19 @@ fn render_mcp_report_json_for(
             }
         }
         Some(args) if is_help_arg(args) => Ok(render_mcp_usage_json(None)),
-        Some("show") => Ok(render_mcp_usage_json(Some("show"))),
+        // #830: `claw mcp show` with no server name is a missing required
+        // argument, not an unknown action. Emit a dedicated error_kind so
+        // machine consumers can distinguish "I know show, but need a name"
+        // from "I don't know this action".
+        Some("show") => Ok(serde_json::json!({
+            "kind": "mcp",
+            "action": "show",
+            "status": "error",
+            "ok": false,
+            "error_kind": "missing_argument",
+            "hint": "Usage: claw mcp show <server>\nRun `claw mcp list` to see available servers.",
+            "message": "missing required argument: mcp show requires a server name.",
+        })),
         Some(args) if args.split_whitespace().next() == Some("show") => {
             let mut parts = args.split_whitespace();
             let _ = parts.next();

rust/crates/rusty-claude-cli/src/main.rs

@@ -271,7 +271,9 @@ Run `claw --help` for usage."
 /// matching against the error messages produced throughout the CLI surface.
 fn classify_error_kind(message: &str) -> &'static str {
     // Check specific patterns first (more specific before generic)
-    if message.starts_with("unknown_slash_command:") {
+    if message.starts_with("missing_argument:") || message.starts_with("missing required argument:") {
+        "missing_argument"
+    } else if message.starts_with("unknown_slash_command:") {
         "unknown_slash_command"
     } else if message.starts_with("command_not_found:") {
         "command_not_found"
@@ -1739,6 +1741,21 @@ fn parse_direct_slash_cli_action(
                 }),
             }
         }
+        // #831: resume-safe slash commands invoked directly (claw /status,
+        // claw /diff, claw /version, claw /doctor, claw /sandbox) should
+        // route to the same CliAction as their subcommand equivalents.
+        // Previously they fell through to the generic interactive_only arm.
+        Ok(Some(SlashCommand::Status)) => Ok(CliAction::Status {
+            model: model.to_string(),
+            model_flag_raw: None,
+            permission_mode: permission_mode_override.unwrap_or_else(default_permission_mode),
+            output_format,
+            allowed_tools,
+        }),
+        Ok(Some(SlashCommand::Diff)) => Ok(CliAction::Diff { output_format }),
+        Ok(Some(SlashCommand::Version)) => Ok(CliAction::Version { output_format }),
+        Ok(Some(SlashCommand::Doctor)) => Ok(CliAction::Doctor { output_format }),
+        Ok(Some(SlashCommand::Sandbox)) => Ok(CliAction::Sandbox { output_format }),
         Ok(Some(SlashCommand::Unknown(name))) => {
             // #828: /approve and /deny are valid REPL-only slash commands that
             // are not SlashCommand enum variants (they require an active tool

rust/crates/rusty-claude-cli/tests/output_format_contract.rs

@@ -4054,3 +4054,64 @@ fn resume_safe_interactive_only_hint_includes_resume_suggestion() {
         "/diff hint must suggest --resume (it is resume-safe) (#829): hint={hint:?}"
     );
 }
+
+// #830: claw mcp show (missing server name) must emit missing_argument, not unknown_mcp_action
+#[test]
+fn mcp_show_missing_server_name_emits_missing_argument() {
+    let root = unique_temp_dir("mcp-show-missing-830");
+    std::fs::create_dir_all(&root).expect("create temp dir");
+    let output = run_claw(&root, &["--output-format", "json", "mcp", "show"], &[]);
+    assert_eq!(output.status.code(), Some(1), "mcp show (no name) should exit 1");
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    let stderr = String::from_utf8_lossy(&output.stderr);
+    let j: serde_json::Value =
+        serde_json::from_str(stdout.trim()).expect("mcp show (no name) must emit JSON (#830)");
+    assert_eq!(
+        j["error_kind"], "missing_argument",
+        "mcp show (no name) must emit missing_argument, not unknown_mcp_action (#830): {j}"
+    );
+    assert_ne!(
+        j["error_kind"], "unknown_mcp_action",
+        "mcp show (no name) must not emit unknown_mcp_action (#830): {j}"
+    );
+    let hint = j["hint"].as_str().unwrap_or("");
+    assert!(
+        hint.contains("claw mcp show") || hint.contains("mcp list"),
+        "mcp show (no name) hint should mention usage (#830): {hint:?}"
+    );
+    assert!(
+        stderr.is_empty(),
+        "mcp show (no name) JSON must have empty stderr (#830): {stderr:?}"
+    );
+}
+
+// #831: direct-slash resume-safe commands must route to their CliAction equivalents
+#[test]
+fn direct_slash_resume_safe_commands_route_correctly() {
+    let root = unique_temp_dir("direct-slash-resume-831");
+    std::fs::create_dir_all(&root).expect("create temp dir");
+    // /version, /doctor, /sandbox, /diff all work without --resume
+    for (cmd, expected_kind) in &[
+        ("/version", "version"),
+        ("/sandbox", "sandbox"),
+        ("/diff", "diff"),
+    ] {
+        let output = run_claw(&root, &["--output-format", "json", cmd], &[]);
+        let stdout = String::from_utf8_lossy(&output.stdout);
+        let j: serde_json::Value = serde_json::from_str(stdout.trim())
+            .unwrap_or_else(|_| panic!("{cmd} must emit JSON (#831), got: {stdout:?}"));
+        assert_eq!(
+            j["status"], "ok",
+            "{cmd} direct slash must exit ok (#831): {j}"
+        );
+        assert_ne!(
+            j["error_kind"], "interactive_only",
+            "{cmd} direct slash must not emit interactive_only (#831): {j}"
+        );
+        let kind = j["kind"].as_str().unwrap_or("");
+        assert_eq!(
+            kind, *expected_kind,
+            "{cmd} direct slash must emit kind={expected_kind} (#831): {j}"
+        );
+    }
+}