print "At $hash{alerts}[0]{timestamp}: $hash{alerts}[0]{text}\n";
                   ^    ^      ^
                   |    |      |
                   |    |      + - hash key
                   |    + - zeroth element of array
                   + - hash key

# {} means hash; [] means array

##</code><code>##

say "$_ => $hash{$_}" for keys %hash;

##</code><code>##

alerts => ARRAY(0x2562880)
recovery_alerts => 0
bad_alerts => 1

##</code><code>##

print $hash{alerts}[0];

##</code><code>##

HASH(0x379350)

##</code><code>##

'alerts' => [
                {
                ^
                |
                + - beginning of hash

##</code><code>##

say "$_ => $hash{alerts}[0]{$_}" for keys %{$hash{alerts}[0]};

##</code><code>##

min_failure_count => 3
status_history => HASH(0x4ec628)
status_code => 1
original_status_code => BAD
dimensions => HASH(0x4f9440)
best_group => NO GROUP
timestamp => 1347395226
text => 95.019 (value) &gt; 95 (max limit) between Tue 20:19 - Tue 20:20 (UTC)
window_size => 3
check_type => system.fs-used_pct

##</code><code>##

print "At $hash{alerts}[0]{timestamp}: $hash{alerts}[0]{text}\n";
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^^^^^^