simplify experimental enum variant support

Co-authored-by: Codex <noreply@openai.com>

codex-rs/app-server-protocol/src/experimental_api.rs

@@ -30,8 +30,6 @@ pub enum ExperimentalEnumVariantEncoding {
     StringLiteral,
     /// A tagged object arm, such as `{ "type": "chatgptAuthTokens", ... }`.
     TaggedObject { tag_name: &'static str },
-    /// An externally tagged object arm, such as `{ "reject": { ... } }`.
-    ExternallyTaggedObject,
 }
 
 /// Describes an experimental enum variant on a specific type.

codex-rs/app-server-protocol/src/export.rs

@@ -880,9 +880,6 @@ fn ts_union_arm_matches_experimental_enum_variant(
         ExperimentalEnumVariantEncoding::TaggedObject { tag_name } => {
             ts_object_arm_has_string_property(arm, tag_name, variant.serialized_name)
         }
-        ExperimentalEnumVariantEncoding::ExternallyTaggedObject => {
-            ts_object_arm_has_property(arm, variant.serialized_name)
-        }
     }
 }
 
@@ -905,17 +902,6 @@ fn ts_object_arm_has_string_property(arm: &str, property_name: &str, property_va
     false
 }
 
-fn ts_object_arm_has_property(arm: &str, property_name: &str) -> bool {
-    let Some((open, close)) = find_top_level_brace_span(arm) else {
-        return false;
-    };
-    let inner = &arm[open + 1..close];
-    split_top_level(inner, ',').into_iter().any(|field| {
-        let field = strip_leading_block_comments(field.as_str());
-        parse_property_name(field).is_some_and(|name| name == property_name)
-    })
-}
-
 fn json_schema_matches_experimental_enum_variant(
     schema: &Value,
     variant: &ExperimentalEnumVariant,
@@ -927,9 +913,6 @@ fn json_schema_matches_experimental_enum_variant(
         ExperimentalEnumVariantEncoding::TaggedObject { tag_name } => {
             json_schema_has_tagged_variant(schema, tag_name, variant.serialized_name)
         }
-        ExperimentalEnumVariantEncoding::ExternallyTaggedObject => {
-            json_schema_has_property(schema, variant.serialized_name)
-        }
     }
 }
 
@@ -957,16 +940,6 @@ fn json_schema_has_tagged_variant(schema: &Value, tag_name: &str, tag_value: &st
         .is_some_and(|tag_schema| json_schema_matches_string_literal(tag_schema, tag_value))
 }
 
-fn json_schema_has_property(schema: &Value, property_name: &str) -> bool {
-    let Value::Object(map) = schema else {
-        return false;
-    };
-    let Some(properties) = map.get("properties").and_then(Value::as_object) else {
-        return false;
-    };
-    properties.contains_key(property_name)
-}
-
 fn strip_leading_block_comments(input: &str) -> &str {
     let mut rest = input.trim_start();
     loop {

codex-rs/codex-experimental-api-macros/src/lib.rs

@@ -262,9 +262,7 @@ fn experimental_enum_variant_registration(
             crate::experimental_api::ExperimentalEnumVariantEncoding::StringLiteral
         }
     } else {
-        quote! {
-            crate::experimental_api::ExperimentalEnumVariantEncoding::ExternallyTaggedObject
-        }
+        return None;
     };
 
     Some(quote! {