fix(protocol): align trace schemas with v2/v3 classify rules

RecordedTrace validation now follows classify_value — numeric version
selects v3, otherwise v2 — so mixed pages/states and v2 envelopes with
a version field fail Schema checks before Recall import. Keep standalone
trace_step as a v2|v3 union for tools that validate a single step.

crates/bsk-protocol/src/tools/record.rs

@@ -16,6 +16,7 @@ pub use super::record_v3::{
     VOM_FORMAT_VERSION,
 };
 
+/// Logical v2 identifier. Not a wire field — v2 envelopes omit `version`.
 pub const TRACE_VERSION_V2: u32 = 2;
 
 // ---------------------------------------------------------------------------
@@ -45,6 +46,10 @@ pub struct RecordStopParams {
 }
 
 /// Wire trace payload — v2 (legacy `pages[]`) or v3 (`version: 3`, `states[]`).
+///
+/// Classification matches [`RecordedTrace::classify_value`]: a numeric `version`
+/// selects v3 (and forbids `pages[]`); otherwise the envelope is v2 and must
+/// not include `states[]`.
 #[derive(Debug, Clone, PartialEq)]
 pub enum RecordedTrace {
     V2(TraceV2),
@@ -104,12 +109,134 @@ impl JsonSchema for RecordedTrace {
     }
 
     fn json_schema(generator: &mut schemars::SchemaGenerator) -> schemars::schema::Schema {
+        // Mirror classify_value: a numeric `version` selects v3; otherwise v2.
+        // TraceV2 stays open for unknown extension fields but forbids `states[]`
+        // and a numeric `version`. TraceV3 already denies `pages[]`.
+        let mut version_props = schemars::Map::new();
+        version_props.insert(
+            "version".into(),
+            schemars::schema::SchemaObject {
+                instance_type: Some(schemars::schema::InstanceType::Integer.into()),
+                ..Default::default()
+            }
+            .into(),
+        );
+        let mut required = schemars::Set::new();
+        required.insert("version".into());
+
         schemars::schema::SchemaObject {
             subschemas: Some(Box::new(schemars::schema::SubschemaValidation {
-                one_of: Some(vec![
-                    generator.subschema_for::<TraceV2>(),
-                    generator.subschema_for::<TraceV3>(),
-                ]),
+                if_schema: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        object: Some(Box::new(schemars::schema::ObjectValidation {
+                            properties: version_props,
+                            required,
+                            ..Default::default()
+                        })),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                then_schema: Some(Box::new(generator.subschema_for::<TraceV3>())),
+                else_schema: Some(Box::new(generator.subschema_for::<TraceV2>())),
+                ..Default::default()
+            })),
+            ..Default::default()
+        }
+        .into()
+    }
+}
+
+/// One recorded step — v2 (`page`) or v3 (`state` / `result.state`).
+///
+/// Classification matches [`RecordedStep::classify_value`]: `state` selects v3
+/// (and forbids `page`); otherwise the step is v2 and must include `page`.
+#[derive(Debug, Clone, PartialEq)]
+pub enum RecordedStep {
+    V2(StepV2),
+    V3(StepV3),
+}
+
+impl RecordedStep {
+    pub fn classify_value(v: &serde_json::Value) -> Result<Self, String> {
+        if v.get("state").is_some() {
+            if v.get("page").is_some() {
+                return Err("step v3 must not include legacy page".into());
+            }
+            return serde_json::from_value(v.clone())
+                .map(RecordedStep::V3)
+                .map_err(|e| e.to_string());
+        }
+        if v.get("page").is_some() {
+            return serde_json::from_value(v.clone())
+                .map(RecordedStep::V2)
+                .map_err(|e| e.to_string());
+        }
+        Err("ambiguous or unparseable step".into())
+    }
+}
+
+impl Serialize for RecordedStep {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            RecordedStep::V2(s) => s.serialize(serializer),
+            RecordedStep::V3(s) => s.serialize(serializer),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for RecordedStep {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let value = serde_json::Value::deserialize(deserializer)?;
+        Self::classify_value(&value).map_err(serde::de::Error::custom)
+    }
+}
+
+impl JsonSchema for RecordedStep {
+    fn schema_name() -> String {
+        "RecordedStep".into()
+    }
+
+    fn json_schema(generator: &mut schemars::SchemaGenerator) -> schemars::schema::Schema {
+        // Mirror classify_value: `state` selects v3; otherwise v2.
+        // Mixed page + state is rejected at this layer because StepV2/StepV3
+        // still allow unknown extension fields.
+        let mut required = schemars::Set::new();
+        required.insert("state".into());
+        let mut mixed_keys = schemars::Set::new();
+        mixed_keys.insert("page".into());
+        mixed_keys.insert("state".into());
+
+        schemars::schema::SchemaObject {
+            subschemas: Some(Box::new(schemars::schema::SubschemaValidation {
+                if_schema: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        object: Some(Box::new(schemars::schema::ObjectValidation {
+                            required,
+                            ..Default::default()
+                        })),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                then_schema: Some(Box::new(generator.subschema_for::<StepV3>())),
+                else_schema: Some(Box::new(generator.subschema_for::<StepV2>())),
+                not: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        object: Some(Box::new(schemars::schema::ObjectValidation {
+                            required: mixed_keys,
+                            ..Default::default()
+                        })),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
                 ..Default::default()
             })),
             ..Default::default()
@@ -204,26 +331,43 @@ mod tests {
         assert!(serde_json::from_value::<TraceV3>(unsupported).is_err());
     }
 
+    fn assert_classifies_by_integer_version(schema: &serde_json::Value) {
+        assert_eq!(
+            schema["if"]["required"],
+            json!(["version"]),
+            "numeric version is the RecordedTrace classification key"
+        );
+        assert_eq!(schema["if"]["properties"]["version"]["type"], "integer");
+        assert_eq!(schema["then"]["$ref"], "#/definitions/TraceV3");
+        assert_eq!(schema["else"]["$ref"], "#/definitions/TraceV2");
+    }
+
     #[test]
     fn recorded_trace_schema_includes_v2_and_v3() {
         let schema = serde_json::to_value(schemars::schema_for!(RecordStopResult)).unwrap();
-        let variants = schema["definitions"]["RecordedTrace"]["oneOf"]
-            .as_array()
-            .expect("RecordedTrace schema should use oneOf");
+        assert_classifies_by_integer_version(&schema["definitions"]["RecordedTrace"]);
+        assert_eq!(
+            schema["definitions"]["TraceV3"]["properties"]["version"]["const"],
+            3
+        );
+    }
 
-        assert_eq!(variants.len(), 2);
-        let trace_schema = schema["definitions"]["TraceV3"].clone();
-        assert_eq!(trace_schema["properties"]["version"]["const"], 3);
+    #[test]
+    fn recorded_trace_schema_follows_classify_value() {
+        let standalone = serde_json::to_value(schemars::schema_for!(RecordedTrace)).unwrap();
+        assert_classifies_by_integer_version(&standalone);
+        assert!(standalone["definitions"].get("TraceV2").is_some());
+        assert!(standalone["definitions"].get("TraceV3").is_some());
+
+        let stop_result = serde_json::to_value(schemars::schema_for!(RecordStopResult)).unwrap();
+        assert_classifies_by_integer_version(&stop_result["definitions"]["RecordedTrace"]);
     }
 
     #[test]
     fn standalone_trace_schema_is_recorded_trace_union() {
         let schema = serde_json::to_value(schemars::schema_for!(RecordedTrace)).unwrap();
         assert_eq!(schema["title"], "RecordedTrace");
-        let variants = schema["oneOf"]
-            .as_array()
-            .expect("standalone trace schema should be a v2|v3 oneOf");
-        assert_eq!(variants.len(), 2);
+        assert_classifies_by_integer_version(&schema);
         assert!(schema["definitions"].get("TraceV2").is_some());
         assert!(schema["definitions"].get("TraceV3").is_some());
     }
@@ -242,4 +386,70 @@ mod tests {
             other => panic!("expected v2, got {other:?}"),
         }
     }
+
+    fn v2_click() -> serde_json::Value {
+        json!({
+            "op": "click",
+            "id": 1,
+            "page": "p1",
+            "target": { "tag": "button", "role": "button", "name": "发布" }
+        })
+    }
+
+    fn v3_click() -> serde_json::Value {
+        json!({
+            "op": "click",
+            "id": 1,
+            "state": "s1",
+            "result": { "state": "s2" },
+            "target": { "ref": "e1", "role": "button", "name": "发布" }
+        })
+    }
+
+    fn assert_step_classifies_by_state(schema: &serde_json::Value) {
+        assert_eq!(
+            schema["if"]["required"],
+            json!(["state"]),
+            "state is the RecordedStep classification key"
+        );
+        assert_eq!(schema["then"]["$ref"], "#/definitions/StepV3");
+        assert_eq!(schema["else"]["$ref"], "#/definitions/StepV2");
+        let mut forbidden = schema["not"]["required"]
+            .as_array()
+            .expect("RecordedStep schema must reject mixed page + state steps")
+            .iter()
+            .filter_map(|v| v.as_str())
+            .collect::<Vec<_>>();
+        forbidden.sort_unstable();
+        assert_eq!(forbidden, ["page", "state"]);
+    }
+
+    #[test]
+    fn recorded_step_classifies_v2_and_v3() {
+        match RecordedStep::classify_value(&v2_click()).unwrap() {
+            RecordedStep::V2(StepV2::Click { .. }) => {}
+            other => panic!("expected v2 click, got {other:?}"),
+        }
+        match RecordedStep::classify_value(&v3_click()).unwrap() {
+            RecordedStep::V3(StepV3::Click { .. }) => {}
+            other => panic!("expected v3 click, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn recorded_step_rejects_mixed_page_and_state() {
+        let mut mixed = v2_click();
+        mixed["state"] = json!("s1");
+        mixed["result"] = json!({ "state": "s2" });
+        assert!(RecordedStep::classify_value(&mixed).is_err());
+    }
+
+    #[test]
+    fn recorded_step_schema_follows_classify_value() {
+        let schema = serde_json::to_value(schemars::schema_for!(RecordedStep)).unwrap();
+        assert_eq!(schema["title"], "RecordedStep");
+        assert_step_classifies_by_state(&schema);
+        assert!(schema["definitions"].get("StepV2").is_some());
+        assert!(schema["definitions"].get("StepV3").is_some());
+    }
 }

crates/bsk-protocol/src/tools/record_v2.rs

@@ -107,8 +107,9 @@ pub enum StepV2 {
 /// Persisted user-action trace exported by legacy `tool.record_stop` / `await`.
 ///
 /// Unknown extension fields are ignored so older traces remain readable.
-/// Mixed v2/v3 envelopes are rejected by `RecordedTrace` classification.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+/// `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace`
+/// classification — serde still ignores them, but the JSON Schema rejects them.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct TraceV2 {
     /// RFC 3339 timestamp when recording stopped.
     pub recorded_at: String,
@@ -121,6 +122,70 @@ pub struct TraceV2 {
     pub steps: Vec<StepV2>,
 }
 
+fn constrain_trace_v2_schema(mut schema: schemars::schema::Schema) -> schemars::schema::Schema {
+    let schemars::schema::Schema::Object(obj) = &mut schema else {
+        return schema;
+    };
+    obj.metadata().title = Some("TraceV2".into());
+    obj.metadata().description = Some(
+        "Persisted user-action trace exported by legacy `tool.record_stop` / `await`.\n\n\
+         Unknown extension fields are ignored so older traces remain readable. \
+         `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace` classification."
+            .into(),
+    );
+
+    let object = obj.object.get_or_insert_with(Default::default);
+    object
+        .properties
+        .insert("states".into(), schemars::schema::Schema::Bool(false));
+    object.properties.insert(
+        "version".into(),
+        schemars::schema::SchemaObject {
+            metadata: Some(Box::new(schemars::schema::Metadata {
+                description: Some(
+                    "Numeric version selects Trace v3. Legacy v2 envelopes omit this field.".into(),
+                ),
+                ..Default::default()
+            })),
+            subschemas: Some(Box::new(schemars::schema::SubschemaValidation {
+                not: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        instance_type: Some(schemars::schema::InstanceType::Integer.into()),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                ..Default::default()
+            })),
+            ..Default::default()
+        }
+        .into(),
+    );
+    schema
+}
+
+impl JsonSchema for TraceV2 {
+    fn schema_name() -> String {
+        "TraceV2".into()
+    }
+
+    fn json_schema(generator: &mut schemars::SchemaGenerator) -> schemars::schema::Schema {
+        #[derive(JsonSchema)]
+        #[allow(dead_code)]
+        struct TraceV2Shape {
+            /// RFC 3339 timestamp when recording stopped.
+            recorded_at: String,
+            started_at: Option<String>,
+            purpose: Option<String>,
+            entry: TraceEntry,
+            pages: Vec<PageRefV2>,
+            steps: Vec<StepV2>,
+        }
+
+        constrain_trace_v2_schema(TraceV2Shape::json_schema(generator))
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -248,4 +313,18 @@ mod tests {
             "Trace v2 must keep accepting traces with unknown extension fields"
         );
     }
+
+    #[test]
+    fn trace_v2_schema_forbids_classification_keys() {
+        let schema = serde_json::to_value(schemars::schema_for!(TraceV2)).unwrap();
+        assert_eq!(
+            schema["properties"]["states"],
+            json!(false),
+            "Trace v2 schema must reject states[] (reserved for v3)"
+        );
+        assert_eq!(
+            schema["properties"]["version"]["not"]["type"], "integer",
+            "Trace v2 schema must reject a numeric version (that selects the v3 path)"
+        );
+    }
 }