diff --git a/agentscope-harness/src/main/java/io/agentscope/harness/agent/HarnessAgent.java b/agentscope-harness/src/main/java/io/agentscope/harness/agent/HarnessAgent.java
index 33c717a56..93c260431 100644
--- a/agentscope-harness/src/main/java/io/agentscope/harness/agent/HarnessAgent.java
+++ b/agentscope-harness/src/main/java/io/agentscope/harness/agent/HarnessAgent.java
@@ -459,6 +459,48 @@ public void interrupt(Msg msg) {
         delegate.interrupt(msg);
     }
 
+    /**
+     * Interrupts the in-flight call identified by the given {@link RuntimeContext}.
+     *
+     * @param ctx the runtime context identifying the session to interrupt
+     */
+    public void interrupt(RuntimeContext ctx) {
+        delegate.interrupt(ctx);
+    }
+
+    /**
+     * Interrupts the in-flight call identified by the given {@link RuntimeContext} with an
+     * associated user message.
+     *
+     * @param ctx the runtime context identifying the session to interrupt
+     * @param msg optional user message to attach to the interrupt signal
+     */
+    public void interrupt(RuntimeContext ctx, Msg msg) {
+        delegate.interrupt(ctx, msg);
+    }
+
+    /**
+     * Interrupts the in-flight call for a specific {@code (userId, sessionId)} session.
+     *
+     * @param userId the user id ({@code null} = anonymous / single-tenant)
+     * @param sessionId the session id
+     */
+    public void interrupt(String userId, String sessionId) {
+        delegate.interrupt(userId, sessionId);
+    }
+
+    /**
+     * Interrupts the in-flight call for a specific {@code (userId, sessionId)} session with an
+     * associated user message.
+     *
+     * @param userId the user id ({@code null} = anonymous / single-tenant)
+     * @param sessionId the session id
+     * @param msg optional user message to attach to the interrupt signal
+     */
+    public void interrupt(String userId, String sessionId, Msg msg) {
+        delegate.interrupt(userId, sessionId, msg);
+    }
+
     // -----------------------------------------------------------------
     //  Channel / Gateway
     // -----------------------------------------------------------------
diff --git a/agentscope-harness/src/test/java/io/agentscope/harness/agent/HarnessAgentTest.java b/agentscope-harness/src/test/java/io/agentscope/harness/agent/HarnessAgentTest.java
index abfda8e61..b49c68f08 100644
--- a/agentscope-harness/src/test/java/io/agentscope/harness/agent/HarnessAgentTest.java
+++ b/agentscope-harness/src/test/java/io/agentscope/harness/agent/HarnessAgentTest.java
@@ -758,4 +758,120 @@ private static AgentTool mockAgentTool(String name) {
         when(tool.getParameters()).thenReturn(Map.of("type", "object", "properties", Map.of()));
         return tool;
     }
+
+    @Test
+    void perSessionInterruptPassthrough_targetByUserIdAndSessionId() throws Exception {
+        Files.createDirectories(workspace);
+        Model model = stubModel("ok");
+        HarnessAgent agent =
+                HarnessAgent.builder()
+                        .name("t")
+                        .model(model)
+                        .workspace(workspace)
+                        .abstractFilesystem(new LocalFilesystem(workspace))
+                        .build();
+
+        // Activate two distinct sessions by accessing their state.
+        String uid = "u1";
+        String sidA = "sess-A";
+        String sidB = "sess-B";
+        agent.getDelegate().getAgentState(uid, sidA);
+        agent.getDelegate().getAgentState(uid, sidB);
+
+        // Interrupt session A only.
+        agent.interrupt(uid, sidA);
+
+        assertTrue(
+                agent.getDelegate().getAgentState(uid, sidA).interruptControl().isInterrupted(),
+                "session A should be interrupted");
+        assertFalse(
+                agent.getDelegate().getAgentState(uid, sidB).interruptControl().isInterrupted(),
+                "session B should NOT be interrupted");
+    }
+
+    @Test
+    void perSessionInterruptPassthrough_targetByUserIdAndSessionIdWithMsg() throws Exception {
+        Files.createDirectories(workspace);
+        Model model = stubModel("ok");
+        HarnessAgent agent =
+                HarnessAgent.builder()
+                        .name("t")
+                        .model(model)
+                        .workspace(workspace)
+                        .abstractFilesystem(new LocalFilesystem(workspace))
+                        .build();
+
+        String uid = "u1";
+        String sid = "sess-X";
+        agent.getDelegate().getAgentState(uid, sid);
+
+        Msg interruptMsg =
+                Msg.builder()
+                        .name("user")
+                        .role(MsgRole.USER)
+                        .content(TextBlock.builder().text("stop now").build())
+                        .build();
+        agent.interrupt(uid, sid, interruptMsg);
+
+        var ctrl = agent.getDelegate().getAgentState(uid, sid).interruptControl();
+        assertTrue(ctrl.isInterrupted());
+        assertNotNull(ctrl.getUserMessage());
+        assertEquals("stop now", ctrl.getUserMessage().getTextContent());
+    }
+
+    @Test
+    void perSessionInterruptPassthrough_targetByRuntimeContext() throws Exception {
+        Files.createDirectories(workspace);
+        Model model = stubModel("ok");
+        HarnessAgent agent =
+                HarnessAgent.builder()
+                        .name("t")
+                        .model(model)
+                        .workspace(workspace)
+                        .abstractFilesystem(new LocalFilesystem(workspace))
+                        .build();
+
+        RuntimeContext ctx = RuntimeContext.builder().userId("u2").sessionId("sess-RC").build();
+        agent.getDelegate().getAgentState(ctx.getUserId(), ctx.getSessionId());
+
+        agent.interrupt(ctx);
+
+        assertTrue(
+                agent.getDelegate()
+                        .getAgentState(ctx.getUserId(), ctx.getSessionId())
+                        .interruptControl()
+                        .isInterrupted());
+    }
+
+    @Test
+    void perSessionInterruptPassthrough_targetByRuntimeContextWithMsg() throws Exception {
+        Files.createDirectories(workspace);
+        Model model = stubModel("ok");
+        HarnessAgent agent =
+                HarnessAgent.builder()
+                        .name("t")
+                        .model(model)
+                        .workspace(workspace)
+                        .abstractFilesystem(new LocalFilesystem(workspace))
+                        .build();
+
+        RuntimeContext ctx = RuntimeContext.builder().userId("u3").sessionId("sess-RC2").build();
+        agent.getDelegate().getAgentState(ctx.getUserId(), ctx.getSessionId());
+
+        Msg interruptMsg =
+                Msg.builder()
+                        .name("user")
+                        .role(MsgRole.USER)
+                        .content(TextBlock.builder().text("cancel").build())
+                        .build();
+        agent.interrupt(ctx, interruptMsg);
+
+        var ctrl =
+                agent.getDelegate()
+                        .getAgentState(ctx.getUserId(), ctx.getSessionId())
+                        .interruptControl();
+        assertTrue(ctrl.isInterrupted());
+        assertNotNull(ctrl.getUserMessage());
+        assertEquals("cancel", ctrl.getUserMessage().getTextContent());
+    }
 }