diff --git a/desktop/src-tauri/src/commands/admin/mod.rs b/desktop/src-tauri/src/commands/admin/mod.rs
index 010f9760b..cd69bb60d 100644
--- a/desktop/src-tauri/src/commands/admin/mod.rs
+++ b/desktop/src-tauri/src/commands/admin/mod.rs
@@ -172,14 +172,16 @@ async fn admin_probe_inner(
         return Ok(AdminProbeResult::NetworkOrIntercepted);
     }
 
-    // Step 3: success without auth → disabled mode (if body is a valid probe).
+    // Step 3: success without auth → disabled mode (only when the body is a
+    // coherent disabled-mode probe: status ok, authMode disabled, no
+    // principal, no capabilities). A 200 in any other shape or mode is a
+    // contract violation (token/nip98 must 401 an unauthenticated caller);
+    // classify defensively.
     if resp.status().is_success() {
         let content_type = response_content_type(&resp);
         let bytes = read_bounded(resp, PROBE_JSON_CAP).await?;
         return Ok(match parse_probe(&content_type, &bytes) {
-            Some(p) if p.auth_mode == "disabled" => AdminProbeResult::Disabled,
-            // A 200 in any other mode is a contract violation (token/nip98
-            // must 401 an unauthenticated caller); classify defensively.
+            Some(p) if p.is_coherent_disabled() => AdminProbeResult::Disabled,
             _ => AdminProbeResult::NotAdminApi,
         });
     }
@@ -223,11 +225,16 @@ async fn admin_probe_inner(
                 let content_type = response_content_type(&auth_resp);
                 let bytes = read_bounded(auth_resp, PROBE_JSON_CAP).await?;
                 return Ok(match parse_probe(&content_type, &bytes) {
-                    // Relay resolves role/source for the authenticated
-                    // principal; carry them through for the staffing tab.
-                    Some(p) => AdminProbeResult::Nip98Authorized {
-                        role: p.role,
-                        source: p.source,
+                    // Trust the 2xx only when the full NIP-98 invariant holds;
+                    // carry the relay-resolved role/source for the staffing tab.
+                    Some(p) => match p.authorized_principal() {
+                        Some((role, source)) => AdminProbeResult::Nip98Authorized {
+                            role: Some(role.as_str().to_string()),
+                            source: Some(source.as_str().to_string()),
+                        },
+                        // Structurally a probe body but not a coherent
+                        // authorized NIP-98 response: fail closed.
+                        None => AdminProbeResult::NotAdminApi,
                     },
                     // 2xx but not a probe shape: endpoint exists but isn't
                     // the admin API.
@@ -296,23 +303,109 @@ async fn read_bounded(resp: reqwest::Response, cap: u64) -> Result<Vec<u8>, Stri
 /// The relay's `/probe` response contract (`ProbeResponse` in the relay's
 /// `api/admin/mod.rs`, serialised `rename_all = "camelCase"`).
 ///
-/// Only the fields the desktop consumes are typed. `role`/`source` are
-/// present (non-null) only in nip98 mode with a resolved principal; they are
-/// `null` in token/disabled modes.
+/// All six fields are required and typed; deserialisation rejects a body that
+/// omits any field or carries a wrong-typed one, so an unrelated JSON endpoint
+/// cannot be mistaken for the admin API. Unknown fields are tolerated for
+/// forward compatibility. Structural validity alone does NOT authorize: a
+/// deserialised `ProbeWire` still has to pass [`ProbeWire::authorized_principal`]
+/// or [`ProbeWire::is_coherent_disabled`] before its state is trusted.
 #[derive(serde::Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct ProbeWire {
-    #[allow(dead_code)]
     status: String,
     auth_mode: String,
     role: Option<String>,
     source: Option<String>,
-    #[allow(dead_code)]
     can_act: bool,
-    #[allow(dead_code)]
     can_staff: bool,
 }
 
+/// The relay's resolved principal role. Closed vocabulary — an unknown string
+/// fails to parse and denies authorization.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum ProbeRole {
+    Operator,
+    Moderator,
+}
+
+impl ProbeRole {
+    fn parse(s: &str) -> Option<Self> {
+        match s {
+            "operator" => Some(Self::Operator),
+            "moderator" => Some(Self::Moderator),
+            _ => None,
+        }
+    }
+
+    fn as_str(self) -> &'static str {
+        match self {
+            Self::Operator => "operator",
+            Self::Moderator => "moderator",
+        }
+    }
+}
+
+/// How the relay established the principal's role. Closed vocabulary.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum ProbeSource {
+    Config,
+    OwnerFallback,
+    Db,
+}
+
+impl ProbeSource {
+    fn parse(s: &str) -> Option<Self> {
+        match s {
+            "config" => Some(Self::Config),
+            "owner_fallback" => Some(Self::OwnerFallback),
+            "db" => Some(Self::Db),
+            _ => None,
+        }
+    }
+
+    fn as_str(self) -> &'static str {
+        match self {
+            Self::Config => "config",
+            Self::OwnerFallback => "owner_fallback",
+            Self::Db => "db",
+        }
+    }
+}
+
+impl ProbeWire {
+    /// Validate the complete NIP-98 authorization invariant and return the
+    /// typed principal only when every field is coherent with the relay
+    /// contract: `status == "ok"`, `authMode == "nip98"`, a recognised
+    /// non-null `role`/`source`, `canAct == true`, and
+    /// `canStaff == (role == operator)`. Any deviation yields `None`, so the
+    /// caller classifies the response `NotAdminApi` rather than trusting a
+    /// fail-open 2xx.
+    fn authorized_principal(&self) -> Option<(ProbeRole, ProbeSource)> {
+        if self.status != "ok" || self.auth_mode != "nip98" {
+            return None;
+        }
+        let role = ProbeRole::parse(self.role.as_deref()?)?;
+        let source = ProbeSource::parse(self.source.as_deref()?)?;
+        if !self.can_act || self.can_staff != (role == ProbeRole::Operator) {
+            return None;
+        }
+        Some((role, source))
+    }
+
+    /// Validate the disabled-mode invariant for an unauthenticated 200:
+    /// `status == "ok"`, `authMode == "disabled"`, no principal, no
+    /// capabilities. Any deviation is a contract violation (token/nip98 must
+    /// 401 an unauthenticated caller).
+    fn is_coherent_disabled(&self) -> bool {
+        self.status == "ok"
+            && self.auth_mode == "disabled"
+            && self.role.is_none()
+            && self.source.is_none()
+            && !self.can_act
+            && !self.can_staff
+    }
+}
+
 /// Parse a `/probe` response body into a [`ProbeWire`], returning `None` when
 /// the Content-Type is not JSON or the body does not match the probe contract.
 ///
diff --git a/desktop/src-tauri/src/commands/admin/mod_tests.rs b/desktop/src-tauri/src/commands/admin/mod_tests.rs
index 845780b20..92950c231 100644
--- a/desktop/src-tauri/src/commands/admin/mod_tests.rs
+++ b/desktop/src-tauri/src/commands/admin/mod_tests.rs
@@ -153,6 +153,91 @@ fn parse_probe_rejects_non_object() {
     assert!(parse_probe("application/json", b"not json").is_none());
 }
 
+// ── authorized_principal / is_coherent_disabled invariants ────────────────
+//
+// Structural deserialisation (parse_probe) is necessary but not sufficient:
+// a 2xx body must also satisfy the full relay contract before its state is
+// trusted. These pin every branch of that invariant.
+
+/// Parse a body known to be structurally valid, then validate it.
+fn authorized(body: &str) -> Option<(ProbeRole, ProbeSource)> {
+    parse_probe("application/json", body.as_bytes())
+        .expect("structurally valid probe")
+        .authorized_principal()
+}
+
+#[test]
+fn authorized_principal_accepts_every_coherent_shape() {
+    // Operator (canStaff true) and moderator (canStaff false) across all three
+    // recognised sources — each must yield the typed principal.
+    let cases: &[(String, ProbeRole, ProbeSource)] = &[
+        (
+            probe_json("nip98", r#""operator""#, r#""config""#, true, true),
+            ProbeRole::Operator,
+            ProbeSource::Config,
+        ),
+        (
+            probe_json("nip98", r#""operator""#, r#""owner_fallback""#, true, true),
+            ProbeRole::Operator,
+            ProbeSource::OwnerFallback,
+        ),
+        (
+            probe_json("nip98", r#""moderator""#, r#""db""#, true, false),
+            ProbeRole::Moderator,
+            ProbeSource::Db,
+        ),
+    ];
+    for (body, role, source) in cases {
+        assert_eq!(authorized(body), Some((*role, *source)));
+    }
+}
+
+#[test]
+fn authorized_principal_rejects_every_incoherent_shape() {
+    // Structurally valid probe bodies the relay never emits under nip98;
+    // accepting any is fail-open. One invariant broken per row, top to bottom:
+    // wrong status, non-nip98 authMode, missing role, unknown role, missing
+    // source, unknown source, false canAct, operator lacking canStaff,
+    // moderator carrying canStaff.
+    let pj = probe_json;
+    let cases = [
+        pj("nip98", r#""operator""#, r#""config""#, true, true)
+            .replace(r#""status":"ok""#, r#""status":"error""#),
+        pj("token", "null", "null", false, false),
+        pj("nip98", "null", r#""config""#, true, true),
+        pj("nip98", r#""superuser""#, r#""config""#, true, true),
+        pj("nip98", r#""operator""#, "null", true, true),
+        pj("nip98", r#""operator""#, r#""ldap""#, true, true),
+        pj("nip98", r#""operator""#, r#""config""#, false, true),
+        pj("nip98", r#""operator""#, r#""config""#, true, false),
+        pj("nip98", r#""moderator""#, r#""config""#, true, true),
+    ];
+    for (i, body) in cases.iter().enumerate() {
+        assert_eq!(authorized(body), None, "row {i} must be rejected");
+    }
+}
+
+#[test]
+fn is_coherent_disabled_accepts_only_canonical_disabled() {
+    // Canonical disabled authorizes; nip98 mode and any disabled body claiming
+    // a role/source or a capability is incoherent and must be rejected.
+    let disabled = probe_json("disabled", "null", "null", false, false);
+    assert!(parse_probe("application/json", disabled.as_bytes())
+        .unwrap()
+        .is_coherent_disabled());
+
+    let incoherent = [
+        probe_json("nip98", r#""operator""#, r#""config""#, true, true),
+        probe_json("disabled", r#""operator""#, "null", false, false),
+        probe_json("disabled", "null", "null", true, false),
+    ];
+    for body in &incoherent {
+        assert!(!parse_probe("application/json", body.as_bytes())
+            .unwrap()
+            .is_coherent_disabled());
+    }
+}
+
 // ── Storage core through production code ─────────────────────────────────
 //
 // All tests call `get_admin_origin_core` / `set_admin_origin_core` directly
diff --git a/desktop/src/features/admin-console/AdminConsoleFeedbackTab.tsx b/desktop/src/features/admin-console/AdminConsoleFeedbackTab.tsx
index ed9015f61..bef695799 100644
--- a/desktop/src/features/admin-console/AdminConsoleFeedbackTab.tsx
+++ b/desktop/src/features/admin-console/AdminConsoleFeedbackTab.tsx
@@ -25,6 +25,7 @@ import {
 import {
   type AsyncState,
   type AttachmentMeta,
+  adminErrorMessage,
   CommunityGroupedList,
   DetailRow,
   ErrorMessage,
@@ -331,20 +332,18 @@ function FeedbackStatusControl({
   onStatusChanged: (newStatus: AdminFeedbackStatus) => void;
 }) {
   const [isWorking, setIsWorking] = useState(false);
-  const [error, setError] = useState<string | null>(null);
 
   const statuses: AdminFeedbackStatus[] = ["new", "reviewed", "archived"];
 
   const handleStatusChange = async (newStatus: AdminFeedbackStatus) => {
     if (newStatus === currentStatus) return;
-    setError(null);
     setIsWorking(true);
     try {
       await patchAdminFeedback(origin, feedbackId, newStatus);
       toast.success(`Feedback marked ${newStatus}`);
       onStatusChanged(newStatus);
     } catch (e) {
-      setError(e instanceof Error ? e.message : String(e));
+      toast.error(adminErrorMessage(e));
     } finally {
       setIsWorking(false);
     }
@@ -375,7 +374,6 @@ function FeedbackStatusControl({
           </Button>
         ))}
       </div>
-      {error && <p className="text-xs text-destructive">{error}</p>}
     </div>
   );
 }
diff --git a/desktop/src/features/admin-console/adminConsolePanelEvents.jsdom-test.mjs b/desktop/src/features/admin-console/adminConsolePanelEvents.jsdom-test.mjs
index d118759cf..e9bdda6da 100644
--- a/desktop/src/features/admin-console/adminConsolePanelEvents.jsdom-test.mjs
+++ b/desktop/src/features/admin-console/adminConsolePanelEvents.jsdom-test.mjs
@@ -3099,3 +3099,92 @@ test("feedback-list-refetches-on-back-after-mutation: changing status then navig
 
   await unmount();
 });
+
+test("resolve-rejection-surfaces-parsed-message: a rejected resolve toasts the relay message, not raw JSON", async () => {
+  // A resolve mutation that the relay rejects (e.g. invalid_action_for_target)
+  // must surface the envelope's human message via toast.error — never the raw
+  // JSON envelope and never a success toast.
+  //
+  // Mutation evidence: replace `toast.error(adminErrorMessage(e))` in
+  // handleSubmit with `toast.error(String(e))` → the raw-JSON assertion goes
+  // red because the envelope leaks verbatim.
+
+  const origin = "https://admin.example.com";
+  const pubkey = "f7".repeat(32);
+
+  const openItem = {
+    id: "00000000-0000-0000-0000-0000000000f7",
+    communityId: "comm-1",
+    communityHost: "alpha.example.com",
+    reportEventId: "aa",
+    reporterPubkey: "bb",
+    targetKind: "event",
+    target: "cc",
+    reportType: "spam",
+    status: "open",
+    createdAt: "2024-06-01T12:00:00Z",
+  };
+  const openDetail = {
+    ...openItem,
+    channelId: "00000000-0000-0000-0000-0000000000ff",
+    note: null,
+    resolvedBy: null,
+    resolvedAt: null,
+    actionId: null,
+    message: null,
+  };
+
+  const humanMessage =
+    "action kick requires the report to have an associated channel";
+  // The native command rejects with `admin API error: {envelope}` — exactly the
+  // shape adminErrorMessage strips down to the envelope's `message`.
+  const rawError = `admin API error: {"error":{"code":"invalid_action_for_target","message":"${humanMessage}","requestId":"00000000-0000-0000-0000-0000000000e7"}}`;
+
+  setIpcHandler("admin_list_reports", () => Promise.resolve([openItem]));
+  setIpcHandler("admin_get_report", () => Promise.resolve(openDetail));
+  setIpcHandler("admin_list_feedback", () => Promise.resolve([]));
+  setIpcHandler("admin_resolve_report", () =>
+    Promise.reject(new Error(rawError)),
+  );
+
+  const { container, doRender, unmount } = mountPanel({ origin, pubkey });
+  await doRender();
+  await settle(30);
+  await openFirstReportDetail(container);
+  await settle(20);
+
+  // Select the kick action, then submit — the relay rejects it.
+  const kickBtn = container.querySelector("[data-testid='action-btn-kick']");
+  assert.ok(kickBtn, "kick action must be present (channel is set)");
+  await act(async () => {
+    fireEvent.click(kickBtn);
+    await new Promise((r) => setTimeout(r, 10));
+  });
+  const submit = container.querySelector("[data-testid='resolve-submit-btn']");
+  assert.ok(submit, "resolve submit button must appear after selecting kick");
+  await act(async () => {
+    fireEvent.click(submit);
+    await new Promise((r) => setTimeout(r, 30));
+  });
+  await settle(20);
+
+  // The parsed human message reaches toast.error.
+  assert.ok(
+    capturedErrorToasts.some((m) => m.includes(humanMessage)),
+    `the parsed relay message must surface via toast.error; got: ${JSON.stringify(capturedErrorToasts)}`,
+  );
+  // The raw JSON envelope must NOT leak into any error toast.
+  assert.ok(
+    !capturedErrorToasts.some(
+      (m) => m.includes('{"error"') || m.includes("admin API error:"),
+    ),
+    `the raw JSON envelope must not appear in an error toast; got: ${JSON.stringify(capturedErrorToasts)}`,
+  );
+  // No success toast on a rejected resolve.
+  assert.ok(
+    !capturedToasts.some((m) => m.toLowerCase().includes("resolved")),
+    `no success toast on a rejected resolve; got: ${JSON.stringify(capturedToasts)}`,
+  );
+
+  await unmount();
+});