diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 975d09338..9eb067bc7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -298,6 +298,15 @@ jobs:
         env:
           CI_RUST_SHARD: ${{ matrix.shard }}
         run: python3 scripts/ci_rust_test.py --report target/ci-test-reports/${{ matrix.shard }}.json -- cargo test --locked ${{ matrix.packages }}
+      - name: Run experimental Code Mode and receipt tests
+        if: matrix.shard == 'server'
+        run: |
+          CI_RUST_SHARD=experimental-code-mode \
+            python3 scripts/ci_rust_test.py --report target/ci-test-reports/experimental-code-mode.json -- \
+            cargo test --locked -p webcodex --features experimental-code-mode code_mode
+          CI_RUST_SHARD=experimental-code-mode-receipts \
+            python3 scripts/ci_rust_test.py --report target/ci-test-reports/experimental-code-mode-receipts.json -- \
+            cargo test --locked -p webcodex --features experimental-code-mode receipt_tests
       - name: Upload bounded Rust test evidence
         if: always()
         uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4
diff --git a/src/tool_runtime/control_sidecar.rs b/src/tool_runtime/control_sidecar.rs
index bd84bc4c3..606ecaf25 100644
--- a/src/tool_runtime/control_sidecar.rs
+++ b/src/tool_runtime/control_sidecar.rs
@@ -398,6 +398,7 @@ fn rejection_result(result: ToolResult) -> ToolCallOutcome {
         project: None,
         model_ergonomics: None,
         canonical_audit_output: None,
+        canonical_state_changed: None,
         correlation: Default::default(),
     }
 }
diff --git a/src/tool_runtime/kernel.rs b/src/tool_runtime/kernel.rs
index da2b07955..aebac3e57 100644
--- a/src/tool_runtime/kernel.rs
+++ b/src/tool_runtime/kernel.rs
@@ -118,6 +118,11 @@ pub(crate) struct ToolCallOutcome {
     /// Existing privacy-safe audit projection captured before model compaction.
     /// Never serialized into ToolResult or interpreted as execution authority.
     pub(crate) canonical_audit_output: Option<Value>,
+    /// Canonical pre-model-projection state-change truth for request-local
+    /// internal effect accounting. This is never serialized into ToolResult and
+    /// carries no authorization, source-fence, or replay authority.
+    #[cfg_attr(not(feature = "experimental-code-mode"), allow(dead_code))]
+    pub(crate) canonical_state_changed: Option<bool>,
     /// Trusted internal Window/Workflow Session correlation evidence. This is
     /// adapter metadata only and is never part of the public ToolResult.
     pub(crate) correlation: super::window_activity::ToolCallCorrelation,
@@ -132,6 +137,7 @@ fn session_selector_failure(error: super::SessionSelectorError) -> ToolCallOutco
             project: None,
             model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
             correlation: Default::default(),
         },
         super::SessionSelectorError::RetentionExpired { session_id } => ToolCallOutcome {
@@ -143,6 +149,7 @@ fn session_selector_failure(error: super::SessionSelectorError) -> ToolCallOutco
             project: None,
             model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
             correlation: Default::default(),
         },
     }
@@ -447,6 +454,7 @@ impl ToolRuntime {
                     project: None,
                     model_ergonomics: None,
                     canonical_audit_output: None,
+                    canonical_state_changed: None,
                     correlation: Default::default(),
                 }
             }
@@ -487,6 +495,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -501,6 +510,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -521,6 +531,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -535,6 +546,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -560,6 +572,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -582,6 +595,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -605,6 +619,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -626,6 +641,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -644,6 +660,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -664,6 +681,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -738,6 +756,7 @@ impl ToolRuntime {
                     project: None,
                     model_ergonomics: None,
                     canonical_audit_output: None,
+                    canonical_state_changed: None,
                     correlation: Default::default(),
                 };
             }
@@ -773,6 +792,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -787,6 +807,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -825,6 +846,7 @@ impl ToolRuntime {
                         project: None,
                         model_ergonomics: None,
                         canonical_audit_output: None,
+                        canonical_state_changed: None,
                         correlation: Default::default(),
                     };
                 }
@@ -854,6 +876,7 @@ impl ToolRuntime {
                         project: None,
                         model_ergonomics: None,
                         canonical_audit_output: None,
+                        canonical_state_changed: None,
                         correlation: Default::default(),
                     };
                 }
@@ -920,6 +943,7 @@ impl ToolRuntime {
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             };
         }
@@ -938,6 +962,7 @@ impl ToolRuntime {
                     project: None,
                     model_ergonomics: None,
                     canonical_audit_output: None,
+                    canonical_state_changed: None,
                     correlation: Default::default(),
                 };
             }
@@ -989,6 +1014,7 @@ impl ToolRuntime {
                     project: None,
                     model_ergonomics: None,
                     canonical_audit_output: None,
+                    canonical_state_changed: None,
                     correlation: Default::default(),
                 };
             }
@@ -1011,6 +1037,7 @@ impl ToolRuntime {
                     project: None,
                     model_ergonomics: None,
                     canonical_audit_output: None,
+                    canonical_state_changed: None,
                     correlation: Default::default(),
                 };
             }
@@ -1064,6 +1091,7 @@ impl ToolRuntime {
                     project: None,
                     model_ergonomics: None,
                     canonical_audit_output: None,
+                    canonical_state_changed: None,
                     correlation: Default::default(),
                 };
             }
@@ -1237,6 +1265,7 @@ impl ToolRuntime {
                 recorder_ack_requested,
             );
         }
+        let canonical_state_changed = result.output.get("state_changed").and_then(Value::as_bool);
         // Session/permission evidence is sealed above. The response stage owns
         // canonical audit capture, one-shot model projection, and late sidecars.
         let postprocess::PostRecordResult {
@@ -1260,6 +1289,7 @@ impl ToolRuntime {
             project,
             model_ergonomics: None,
             canonical_audit_output,
+            canonical_state_changed,
             correlation,
         }
     }
diff --git a/src/tool_runtime/orchestration_host.rs b/src/tool_runtime/orchestration_host.rs
index 2146b1324..cb19edc7c 100644
--- a/src/tool_runtime/orchestration_host.rs
+++ b/src/tool_runtime/orchestration_host.rs
@@ -355,7 +355,12 @@ impl OrchestrationEffectAccumulator {
         self.children.remove(&ordinal);
     }
 
-    fn finish(&mut self, ordinal: usize, result: &super::ToolResult) {
+    fn finish(
+        &mut self,
+        ordinal: usize,
+        result: &super::ToolResult,
+        canonical_state_changed: Option<bool>,
+    ) {
         let output = &result.output;
         let execution_state = output.get("execution_state").and_then(Value::as_str);
         let failure_kind = output.get("failure_kind").and_then(Value::as_str);
@@ -413,9 +418,7 @@ impl OrchestrationEffectAccumulator {
             .children
             .get(&ordinal)
             .is_some_and(|child| runtime_tool_metadata(&child.tool).effect == ToolEffect::Mutate);
-        let mutation_state_changed = is_mutation
-            .then(|| output.get("state_changed").and_then(Value::as_bool))
-            .flatten();
+        let mutation_state_changed = is_mutation.then_some(canonical_state_changed).flatten();
         if let Some(child) = self.children.get_mut(&ordinal) {
             child.job_id = None;
             child.continuation = None;
@@ -879,7 +882,7 @@ impl CanonicalOrchestrationHost {
             if outcome.error_status.is_some() {
                 effects.remove(child_ordinal);
             } else if let Some(result) = outcome.result.as_ref() {
-                effects.finish(child_ordinal, result);
+                effects.finish(child_ordinal, result, outcome.canonical_state_changed);
             }
         }
         // Publish effect truth before releasing the sequential scheduling fence:
@@ -935,24 +938,52 @@ mod receipt_tests {
     use super::*;
 
     #[test]
-    fn mutation_result_without_authoritative_state_changed_fails_closed() {
-        let mut effects = OrchestrationEffectAccumulator::default();
-        effects.begin_if_consequential(1, "edit_project_files");
-        effects.finish(
-            1,
-            &crate::tool_runtime::ToolResult::ok(serde_json::json!({
-                "execution_state": "completed"
-            })),
-        );
+    fn mutation_result_uses_preprojection_state_changed_truth() {
+        for state_changed in [false, true] {
+            let mut effects = OrchestrationEffectAccumulator::default();
+            effects.begin_if_consequential(1, "edit_project_files");
+            effects.finish(
+                1,
+                &crate::tool_runtime::ToolResult::ok(serde_json::json!({
+                    "changed": state_changed
+                })),
+                Some(state_changed),
+            );
+
+            let receipt = effects.receipt();
+            assert_eq!(receipt.consequential_calls, 1);
+            assert_eq!(receipt.known_results, 1);
+            assert_eq!(receipt.outcome_unknown, 0);
+            assert_eq!(
+                receipt.children[0].outcome,
+                ConsequentialChildOutcome::KnownResult
+            );
+            assert_eq!(receipt.children[0].success, Some(true));
+            assert_eq!(receipt.children[0].state_changed, Some(state_changed));
+        }
+    }
 
-        let receipt = effects.receipt();
-        assert_eq!(receipt.consequential_calls, 1);
-        assert_eq!(receipt.known_results, 0);
-        assert_eq!(receipt.outcome_unknown, 1);
-        assert_eq!(
-            receipt.children[0].outcome,
-            ConsequentialChildOutcome::OutcomeUnknown
-        );
-        assert_eq!(receipt.children[0].state_changed, None);
+    #[test]
+    fn mutation_result_without_authoritative_state_changed_fails_closed() {
+        for projected_state_changed in [None, Some(false), Some(true)] {
+            let mut effects = OrchestrationEffectAccumulator::default();
+            effects.begin_if_consequential(1, "edit_project_files");
+            let mut output = serde_json::json!({"execution_state": "completed"});
+            if let Some(state_changed) = projected_state_changed {
+                output["state_changed"] = serde_json::json!(state_changed);
+            }
+            effects.finish(1, &crate::tool_runtime::ToolResult::ok(output), None);
+
+            let receipt = effects.receipt();
+            assert_eq!(receipt.consequential_calls, 1);
+            assert_eq!(receipt.known_results, 0);
+            assert_eq!(receipt.outcome_unknown, 1);
+            assert_eq!(
+                receipt.children[0].outcome,
+                ConsequentialChildOutcome::OutcomeUnknown
+            );
+            assert_eq!(receipt.children[0].success, None);
+            assert_eq!(receipt.children[0].state_changed, None);
+        }
     }
 }
diff --git a/src/tool_runtime/specialized.rs b/src/tool_runtime/specialized.rs
index b20b1f0ca..38cee26d0 100644
--- a/src/tool_runtime/specialized.rs
+++ b/src/tool_runtime/specialized.rs
@@ -57,6 +57,7 @@ pub(crate) async fn try_dispatch_specialized_gateway(
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation: Default::default(),
             });
         }
@@ -142,6 +143,7 @@ pub(crate) async fn try_dispatch_specialized_gateway(
                 project: None,
                 model_ergonomics: None,
                 canonical_audit_output: None,
+                canonical_state_changed: None,
                 correlation,
             }
         }
@@ -152,6 +154,7 @@ pub(crate) async fn try_dispatch_specialized_gateway(
             project: None,
             model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
             correlation: Default::default(),
         },
         Err(SpecializedGovernanceDenial::Scope {
@@ -167,6 +170,7 @@ pub(crate) async fn try_dispatch_specialized_gateway(
             project: None,
             model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
             correlation: Default::default(),
         },
     })
diff --git a/src/tool_runtime/tests/code_mode_e2b.rs b/src/tool_runtime/tests/code_mode_e2b.rs
index 1b63a2425..892e1e7c7 100644
--- a/src/tool_runtime/tests/code_mode_e2b.rs
+++ b/src/tool_runtime/tests/code_mode_e2b.rs
@@ -392,7 +392,7 @@ async fn e2b_read_guarded_edit_post_read_preserves_canonical_mutation_truth() {
         const after = await tools.read_files({items:[{path:"src/example.rs"}]});
         text(JSON.stringify({
             edit_success: edit.success,
-            changed: edit.output.state_changed,
+            changed: edit.output.changed,
             after: after.output.items[0].output.text
         }));
     "#;
@@ -440,7 +440,7 @@ async fn e2b_noop_mutation_is_known_false_without_edit_provenance() {
             kind:"edit", path:"src/example.rs", expected_read_revision:revision,
             edits:[{kind:"replace_exact", old_text:"same", new_text:"same"}]
         }]});
-        text(JSON.stringify({success:edit.success, changed:edit.output.state_changed}));
+        text(JSON.stringify({success:edit.success, changed:edit.output.changed}));
     "#;
     let task = spawn_e2b_call(&runtime, &project, &session_id, source, None);
     service_e2b_call(
@@ -483,7 +483,7 @@ async fn e2b_dry_run_is_known_false_and_never_creates_edit_provenance() {
                 edits:[{kind:"replace_exact", old_text:"before", new_text:"after"}]
             }]
         });
-        text(JSON.stringify({success:edit.success, changed:edit.output.state_changed, would_change:edit.output.would_change}));
+        text(JSON.stringify({success:edit.success, changed:edit.output.changed, would_change:edit.output.would_change}));
     "#;
     let task = spawn_e2b_call(&runtime, &project, &session_id, source, None);
     service_e2b_call(
@@ -1135,7 +1135,7 @@ async fn e2b_nested_edit_drives_real_final_changes_baseline_to_full_final_worksp
             kind:"edit",path:"README.md",expected_read_revision:revision,
             edits:[{kind:"replace_exact",old_text:"base readme",new_text:"E2b readme"}]
         }]});
-        text(JSON.stringify({success:edit.success,changed:edit.output.state_changed}));
+        text(JSON.stringify({success:edit.success,changed:edit.output.changed}));
     "#;
     let e2b = spawn_e2b_call(&runtime, &project, &session.session_id, source, None);
     service_e2b_call(
@@ -1281,7 +1281,7 @@ async fn e2b_outer_only_noop_and_prestart_failure_do_not_create_final_changes_el
         &runtime,
         &project,
         &noop.session_id,
-        "const before=await tools.read_files({items:[{path:'README.md'}]}); const revision=before.output.items[0].output.read_revision; const r=await tools.edit_project_files({changes:[{kind:'edit',path:'README.md',expected_read_revision:revision,edits:[{kind:'replace_exact',old_text:'base',new_text:'base'}]}]}); text(String(r.output.state_changed));",
+        "const before=await tools.read_files({items:[{path:'README.md'}]}); const revision=before.output.items[0].output.read_revision; const r=await tools.edit_project_files({changes:[{kind:'edit',path:'README.md',expected_read_revision:revision,edits:[{kind:'replace_exact',old_text:'base',new_text:'base'}]}]}); text(String(r.output.changed));",
         None,
     );
     service_e2b_call(
@@ -1446,7 +1446,7 @@ async fn e2b_parent_omits_retired_continuity_overlays_after_nested_edit() {
                     arguments: json!({
                         "project": project_for_call,
                         "session_id": session_for_call,
-                        "source": "const before=await tools.read_files({items:[{path:'src/example.rs'}]}); const revision=before.output.items[0].output.read_revision; const e=await tools.edit_project_files({changes:[{kind:'edit',path:'src/example.rs',expected_read_revision:revision,edits:[{kind:'replace_exact',old_text:'before',new_text:'after'}]}]}); text(String(e.output.state_changed));"
+                        "source": "const before=await tools.read_files({items:[{path:'src/example.rs'}]}); const revision=before.output.items[0].output.read_revision; const e=await tools.edit_project_files({changes:[{kind:'edit',path:'src/example.rs',expected_read_revision:revision,edits:[{kind:'replace_exact',old_text:'before',new_text:'after'}]}]}); text(String(e.output.changed));"
                     }),
                 },
                 ToolCallContext {
diff --git a/src/tool_runtime/tests/code_mode_e2c.rs b/src/tool_runtime/tests/code_mode_e2c.rs
index 16e171f52..950cdfb0b 100644
--- a/src/tool_runtime/tests/code_mode_e2c.rs
+++ b/src/tool_runtime/tests/code_mode_e2c.rs
@@ -237,7 +237,7 @@ async fn direct_edit(
     );
     let result = task.await.unwrap();
     assert!(result.success, "{result:?}");
-    assert_eq!(result.output["state_changed"], true);
+    assert_eq!(result.output["changed"], true);
 }
 
 fn validator_receipt(result: &ToolResult) -> &Value {
@@ -267,7 +267,7 @@ async fn e2c_guarded_edit_then_check_or_test_keeps_execution_and_source_truth_se
     ] {
         let client = format!("e2c-known-{tool}-{noop}-{exit}");
         let (root, runtime, project, session) = fixture(&client).await;
-        let source = format!("{EDIT} const validation = await tools.{tool}({args}); text({{changed:edit.output.state_changed,success:validation.success,passed:validation.output.passed,source:validation.output.source_state}});");
+        let source = format!("{EDIT} const validation = await tools.{tool}({args}); text({{changed:edit.output.changed,success:validation.success,passed:validation.output.passed,source:validation.output.source_state}});");
         let task = spawn_e2b_call(&runtime, &project, &session, &source, None);
         let request = reach_validation(
             &runtime,
diff --git a/src/tool_runtime/tests/control_sidecars.rs b/src/tool_runtime/tests/control_sidecars.rs
index 992f6652e..983f0f3da 100644
--- a/src/tool_runtime/tests/control_sidecars.rs
+++ b/src/tool_runtime/tests/control_sidecars.rs
@@ -99,6 +99,7 @@ impl Fixture {
             project: None,
             model_ergonomics: None,
             canonical_audit_output: None,
+            canonical_state_changed: None,
             correlation: Default::default(),
         };
         execution.decorate(&mut outcome);