From 259b2adc0745c765bec63f36462b4f2795d24ebe Mon Sep 17 00:00:00 2001
From: Josh Creek <8179928+jcreek@users.noreply.github.com>
Date: Wed, 29 Jul 2026 08:35:20 +0100
Subject: [PATCH] fix(training): Guard GoalRateCallback against a missing
 goal_scored key

The vendored godot_rl sync bridge (Game/addons/godot_rl_agents/sync.gd,
_training_process) snapshots each agent's info dict once per tick and its
own inline comment already flags that reset-timing path as incomplete
("NEEDS REFACTOR"); at least one agent's terminal-step info can arrive
without "goal_scored" at all. Indexing it directly crashed a training run
(20260729-0607-curric-s1-unmask-retry2) within minutes of starting. Skip
episodes missing the key instead of crashing training over a
monitoring-only metric.
---
 training/train.py | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/training/train.py b/training/train.py
index c6553cec..1abcd205 100644
--- a/training/train.py
+++ b/training/train.py
@@ -43,8 +43,15 @@ class GoalRateCallback(BaseCallback):
     def _on_rollout_end(self) -> None:
         if len(self.model.ep_info_buffer) == 0:
             return
-        goal_rate = safe_mean([ep_info["goal_scored"] for ep_info in self.model.ep_info_buffer])
-        self.logger.record("rollout/goal_rate", goal_rate)
+        # The vendored godot_rl sync bridge (Game/addons/godot_rl_agents/sync.gd,
+        # _training_process) snapshots each agent's info dict once per tick and
+        # has its own "NEEDS REFACTOR" comment on the reset-timing path, so an
+        # episode's terminal info entry can arrive without "goal_scored" at all
+        # (observed crashing a run after 2026-07-28). Skip those rather than
+        # crash training over a monitoring-only metric.
+        rates = [ep_info["goal_scored"] for ep_info in self.model.ep_info_buffer if "goal_scored" in ep_info]
+        if rates:
+            self.logger.record("rollout/goal_rate", safe_mean(rates))
 
 
 def parse_args():