Purpose of max_episode_steps in Crafter?

[jens321]

I noticed the Crafter language wrapper specifies a max_steps property, but it seems it's never used: https://github.com/balrog-ai/BALROG/blob/main/balrog/environments/crafter/env.py#L199. In addition, the underlying Crafter environment seems to have its own length property: https://github.com/danijar/crafter/blob/main/crafter/env.py#L29, which is also customizable by BALROG here: https://github.com/balrog-ai/BALROG/blob/main/balrog/config/config.yaml#L67 Hence, I'm wondering if length is the only one needed? And if not, what's the purpose of max_steps?

Thanks!

[DavidePaglieri]

Hi @jens321 , sorry for the delay in getting back to you. Despite the max_steps argument not being used inside the crafter environment, it is taken as a property by the environment wrapper

BALROG/balrog/environments/env_wrapper.py

Lines 18 to 19 in ab4eaee

	def max_steps(self):
	return self.env.max_steps

This is then used in the evaluator here

BALROG/balrog/evaluator.py

Line 280 in ab4eaee

max_steps_per_episode = env.max_steps if self.max_steps_per_episode is None else self.max_steps_per_episode

to determine the maximum number of steps in a way that's easier to handle across the various environments.

While crafter does have a length=10000 argument similarly to in our config file as you pointed out, that is actually not used, and the max_episode_steps in the config defines the maximum episode length. I have removed the length argument from the config in PR #39 to avoid confusions.

I'm closing this issue but feel free to reopen if something is unclear!