diff --git a/src/contracts/toolEffects.ts b/src/contracts/toolEffects.ts
index 6ee083e6b9..c956bc487a 100644
--- a/src/contracts/toolEffects.ts
+++ b/src/contracts/toolEffects.ts
@@ -244,6 +244,7 @@ export const TOOL_EFFECTS: Readonly<Record<string, ToolEffects>> = {
     mutatesSession: true,
     launchesProcess: true,
     accessesNetwork: true,
+    executesForeignCode: true,
     idempotent: false,
   }),
   instrument_with_frida: effects({
diff --git a/src/frida/FridaInstrumentationManager.ts b/src/frida/FridaInstrumentationManager.ts
index 20a709040d..7800ba309f 100644
--- a/src/frida/FridaInstrumentationManager.ts
+++ b/src/frida/FridaInstrumentationManager.ts
@@ -588,10 +588,19 @@ export class FridaInstrumentationManager implements FridaInstrumentationPort {
       return err(unknownFridaSession("resume_frida_session", sessionId));
     if (managed.mode !== "spawn" || managed.targetResumeObserved)
       return err(
-        new AnalysisCapabilityUnavailableError(
-          "frida",
+        new AnalysisInputError(
           "resume_frida_session",
-          "Only a paused process spawned by this session can be resumed.",
+          {
+            userMessage:
+              "Only a paused process spawned by this session can be resumed.",
+          },
+          [
+            {
+              path: ["session_id"],
+              reason: "invalid_value",
+              message: "Select a paused process spawned by this session.",
+            },
+          ],
         ),
       );
     const pendingScripts = [...managed.scripts.values()].filter(
diff --git a/tests/boundary/mcp/fridaLifecycleMcp.test.ts b/tests/boundary/mcp/fridaLifecycleMcp.test.ts
index ac6229e5fa..eb0732776d 100644
--- a/tests/boundary/mcp/fridaLifecycleMcp.test.ts
+++ b/tests/boundary/mcp/fridaLifecycleMcp.test.ts
@@ -298,6 +298,26 @@ it.each(["attached", "during-resume", "after-resume"] as const)(
 
 it("retains detached state and resume evidence when remote cleanup needs retry", async () => {
   const fixture = await connectedFixture();
+  expect(
+    (await fixture.client.listTools()).tools.find(
+      (tool) => tool.name === "close_frida_session",
+    )?.annotations?.destructiveHint,
+  ).toBe(true);
+  const inventory = await fixture.client.callTool({
+    name: "binary_session",
+    arguments: {},
+  });
+  const availability = expandToolAvailability(
+    toolContract("binary_session").outputSchema.parse(
+      inventory.structuredContent,
+    ).result.tool_availability,
+  );
+  expect(
+    availability.find((tool) => tool.name === "close_frida_session"),
+  ).toMatchObject({
+    effects: { executesForeignCode: true },
+    annotations: { destructive: true },
+  });
   const started = await fixture.client.callTool({
     name: "start_frida_session",
     arguments: {
@@ -1434,3 +1454,35 @@ it.each([0, 1, 2, 3, 4, 8])(
     }
   },
 );
+
+it.each(["attached", "resumed"] as const)(
+  "reports %s Frida resume refusal as selected session input",
+  async (state) => {
+    const fixture = await connectedFixture();
+    const started =
+      state === "attached"
+        ? await fixture.manager.startSession({ mode: "attach", pid: 512 })
+        : await fixture.manager.startSession({
+            mode: "spawn",
+            program: "/fixture",
+          });
+    if (!started.ok) throw started.error;
+    const id = started.value.session_id;
+    if (state === "resumed")
+      expect((await fixture.manager.resumeSession(id)).ok).toBe(true);
+    const result = await fixture.client.callTool({
+      name: "resume_frida_session",
+      arguments: { session_id: id },
+    });
+    expect(result.isError).toBe(true);
+    expect(parseMcpToolError(result)).toMatchObject({
+      error: {
+        code: "invalid_request",
+        details: {
+          issues: [{ path: ["session_id"], reason: "invalid_value" }],
+        },
+      },
+    });
+    expect(fixture.controls.resumes).toBe(state === "resumed" ? 1 : 0);
+  },
+);