code-mode: use client cell ids and linear observations

codex-rs/code-mode-protocol/src/lib.rs

@@ -25,6 +25,7 @@ pub use runtime::CreateCellRequest;
 pub use runtime::DEFAULT_EXEC_YIELD_TIME_MS;
 pub use runtime::DEFAULT_MAX_OUTPUT_TOKENS_PER_EXEC_CALL;
 pub use runtime::DEFAULT_WAIT_YIELD_TIME_MS;
+pub use runtime::ObservationGeneration;
 pub use runtime::ObserveOutcome;
 pub use runtime::ObserveRequest;
 pub use runtime::RuntimeResponse;

codex-rs/code-mode-protocol/src/runtime.rs

@@ -14,7 +14,7 @@ pub const DEFAULT_MAX_OUTPUT_TOKENS_PER_EXEC_CALL: usize = 10_000;
 
 #[derive(Clone, Debug, Deserialize, PartialEq, Serialize)]
 pub struct CreateCellRequest {
-    pub idempotency_key: String,
+    pub cell_id: CellId,
     pub tool_call_id: String,
     pub enabled_tools: Vec<ToolDefinition>,
     pub source: String,
@@ -22,11 +22,34 @@ pub struct CreateCellRequest {
 
 #[derive(Clone, Debug, Deserialize, PartialEq, Serialize)]
 pub struct ObserveRequest {
-    pub idempotency_key: String,
     pub cell_id: CellId,
+    pub generation: ObservationGeneration,
     pub yield_time_ms: u64,
 }
 
+#[derive(Clone, Copy, Debug, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
+#[serde(transparent)]
+pub struct ObservationGeneration(u64);
+
+impl ObservationGeneration {
+    pub const INITIAL: Self = Self(0);
+
+    pub const fn new(value: u64) -> Self {
+        Self(value)
+    }
+
+    pub const fn get(self) -> u64 {
+        self.0
+    }
+
+    pub const fn next(self) -> Option<Self> {
+        match self.0.checked_add(1) {
+            Some(value) => Some(Self(value)),
+            None => None,
+        }
+    }
+}
+
 /// A valid result of observing a cell.
 #[derive(Clone, Debug, Deserialize, PartialEq, Serialize)]
 #[serde(tag = "type")]

codex-rs/code-mode-protocol/src/runtime_tests.rs

@@ -34,7 +34,7 @@ fn image(image_url: &str, detail: Option<ImageDetail>) -> FunctionCallOutputCont
 #[test]
 fn requests_round_trip_with_exact_tool_and_namespace_fields() {
     let create = CreateCellRequest {
-        idempotency_key: "thread-3:response-call-7".to_string(),
+        cell_id: CellId::new("cell-a7".to_string()),
         tool_call_id: "response-call-7".to_string(),
         enabled_tools: vec![
             ToolDefinition {
@@ -62,7 +62,7 @@ fn requests_round_trip_with_exact_tool_and_namespace_fields() {
     assert_json_round_trip(
         &create,
         json!({
-            "idempotency_key": "thread-3:response-call-7",
+            "cell_id": "cell-a7",
             "tool_call_id": "response-call-7",
             "enabled_tools": [
                 {
@@ -91,13 +91,13 @@ fn requests_round_trip_with_exact_tool_and_namespace_fields() {
 
     assert_json_round_trip(
         &ObserveRequest {
-            idempotency_key: "thread-3:wait-call-2".to_string(),
             cell_id: CellId::new("cell-a7".to_string()),
+            generation: ObservationGeneration::new(/*value*/ 3),
             yield_time_ms: 250,
         },
         json!({
-            "idempotency_key": "thread-3:wait-call-2",
             "cell_id": "cell-a7",
+            "generation": 3,
             "yield_time_ms": 250,
         }),
     );