🤖 [codex] Honor FIREHOSE_DISABLED when installing the execution extension

CHANGELOG.md

@@ -9,6 +9,15 @@ This changelog covers Firehose-specific changes only. For upstream changes, see
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## Unreleased
+
+### Fixed
+
+- Honor `FIREHOSE_DISABLED` when installing the Firehose execution extension, as
+  well as when initializing the tracer. Previously a plain archive RPC startup
+  could briefly serve requests and then exit because the extension accessed the
+  uninitialized tracer. The normal Firehose-enabled path is unchanged.
+
 ## dev-049d306-fh3.1-3
 
 ### Fixed

src/main.rs

@@ -629,7 +629,9 @@ fn main() -> eyre::Result<()> {
                         tracing::info!("Succeed to register eth_config (EIP-7910) API");
                         Ok(())
                     })
-                    .install_exex("firehose", |ctx| async move {
+                    // The ExEx requires the tracer's global state. A plain RPC node
+                    // with FIREHOSE_DISABLED must skip both initialization and ExEx.
+                    .install_exex_if(!firehose_disabled, "firehose", |ctx| async move {
                         // Box::pin works around a rustc higher-ranked lifetime limitation when
                         // proving the (deeply generic) run_exex future Send inside this closure.
                         Ok(Box::pin(reth_firehose::run_exex(ctx))