diff --git a/codex-rs/core/src/codex.rs b/codex-rs/core/src/codex.rs
index d23981b95..47e252307 100644
--- a/codex-rs/core/src/codex.rs
+++ b/codex-rs/core/src/codex.rs
@@ -831,6 +831,36 @@ async fn submission_loop(
                     }
                 });
             }
+
+            Op::SummarizeContext => {
+                let sess = match sess.as_ref() {
+                    Some(sess) => sess,
+                    None => {
+                        send_no_session_event(sub.id).await;
+                        continue;
+                    }
+                };
+
+                // Create a summarization request as user input
+                const SUMMARIZATION_PROMPT: &str = r#"
+                    Please provide a summary of our conversation so far, highlighting key points,
+                    decisions made, and any important context that would be useful for future reference.
+                    This summary will be used to replace our conversation history with a more concise
+                    version so choose what details you will need to continue your work.
+                    Provide the summary directly without main title.
+                "#;
+
+                let summarization_prompt = vec![InputItem::Text {
+                    text: SUMMARIZATION_PROMPT.to_string(),
+                }];
+
+                // Attempt to inject input into current task
+                if let Err(items) = sess.inject_input(summarization_prompt) {
+                    // No current task, spawn a new one
+                    let task = AgentTask::spawn(sess.clone(), sub.id, items);
+                    sess.set_task(task);
+                }
+            }
         }
     }
     debug!("Agent loop exited");
diff --git a/codex-rs/core/src/protocol.rs b/codex-rs/core/src/protocol.rs
index 08d55b974..aa6728bb0 100644
--- a/codex-rs/core/src/protocol.rs
+++ b/codex-rs/core/src/protocol.rs
@@ -112,6 +112,11 @@ pub enum Op {
 
     /// Request a single history entry identified by `log_id` + `offset`.
     GetHistoryEntryRequest { offset: usize, log_id: u64 },
+
+    /// Request the agent to summarize the current conversation context.
+    /// The agent will use its existing context (either conversation history or previous response id)
+    /// to generate a summary which will be returned as an AgentMessage event.
+    SummarizeContext,
 }
 
 /// Determines the conditions under which the user is consulted to approve
diff --git a/codex-rs/core/tests/summarize_context.rs b/codex-rs/core/tests/summarize_context.rs
new file mode 100644
index 000000000..ecf84c4fd
--- /dev/null
+++ b/codex-rs/core/tests/summarize_context.rs
@@ -0,0 +1,42 @@
+#![expect(clippy::unwrap_used, clippy::expect_used)]
+
+//! Tests for the `Op::SummarizeContext` operation added to verify that
+//! summarization requests are properly handled and injected as user input.
+
+use std::time::Duration;
+
+use codex_core::Codex;
+use codex_core::protocol::EventMsg;
+use codex_core::protocol::Op;
+mod test_support;
+use tempfile::TempDir;
+use test_support::load_default_config_for_test;
+use tokio::time::timeout;
+
+/// Helper function to set up a codex session and wait for it to be configured
+async fn setup_configured_codex_session() -> Codex {
+    let codex_home = TempDir::new().unwrap();
+    let config = load_default_config_for_test(&codex_home);
+    let (codex, _, _) = codex_core::codex_wrapper::init_codex(config).await.unwrap();
+    codex
+}
+
+#[tokio::test]
+async fn test_summarize_context_spawns_new_agent_task() {
+    // Test the specific behavior: when there's no current task,
+    // SummarizeContext should spawn a new AgentTask with the summarization prompt
+    let codex = setup_configured_codex_session().await;
+
+    // At this point, there should be no current task running
+    let _sub_id = codex.submit(Op::SummarizeContext).await.unwrap();
+
+    let event = timeout(Duration::from_secs(5), codex.next_event())
+        .await
+        .expect("timeout waiting for task started event")
+        .expect("codex closed");
+
+    assert!(
+        matches!(event.msg, EventMsg::TaskStarted),
+        "Expected TaskStarted when no current task exists - should spawn new AgentTask"
+    );
+}