feat: support configurable metric_exporter (#10940)

codex-rs/core/config.schema.json

@@ -611,6 +611,14 @@
           "description": "Log user prompt in traces",
           "type": "boolean"
         },
+        "metrics_exporter": {
+          "allOf": [
+            {
+              "$ref": "#/definitions/OtelExporterKind"
+            }
+          ],
+          "description": "Optional metrics exporter"
+        },
         "trace_exporter": {
           "allOf": [
             {

codex-rs/core/src/config/mod.rs

@@ -1808,12 +1808,13 @@ impl Config {
                     .unwrap_or(DEFAULT_OTEL_ENVIRONMENT.to_string());
                 let exporter = t.exporter.unwrap_or(OtelExporterKind::None);
                 let trace_exporter = t.trace_exporter.unwrap_or_else(|| exporter.clone());
+                let metrics_exporter = t.metrics_exporter.unwrap_or(OtelExporterKind::Statsig);
                 OtelConfig {
                     log_user_prompt,
                     environment,
                     exporter,
                     trace_exporter,
-                    metrics_exporter: OtelExporterKind::Statsig,
+                    metrics_exporter,
                 }
             },
         };
@@ -4073,6 +4074,23 @@ model_verbosity = "high"
         Ok(())
     }
 
+    #[test]
+    fn metrics_exporter_defaults_to_statsig_when_missing() -> std::io::Result<()> {
+        let fixture = create_test_fixture()?;
+
+        let config = Config::load_from_base_config_with_overrides(
+            fixture.cfg.clone(),
+            ConfigOverrides {
+                cwd: Some(fixture.cwd()),
+                ..Default::default()
+            },
+            fixture.codex_home(),
+        )?;
+
+        assert_eq!(config.otel.metrics_exporter, OtelExporterKind::Statsig);
+        Ok(())
+    }
+
     #[test]
     fn test_precedence_fixture_with_gpt3_profile() -> std::io::Result<()> {
         let fixture = create_test_fixture()?;

codex-rs/core/src/config/types.rs

@@ -437,6 +437,9 @@ pub struct OtelConfigToml {
 
     /// Optional trace exporter
     pub trace_exporter: Option<OtelExporterKind>,
+
+    /// Optional metrics exporter
+    pub metrics_exporter: Option<OtelExporterKind>,
 }
 
 /// Effective OTEL settings after defaults are applied.