diff --git a/checks/generators/generators1.py b/checks/generators/generators1.py
index 4f3822e..dab7bcb 100644
--- a/checks/generators/generators1.py
+++ b/checks/generators/generators1.py
@@ -1,4 +1,5 @@
-assert list(count_up_to(4)) == [1, 2, 3, 4]
-assert list(count_up_to(1)) == [1]
-assert list(count_up_to(0)) == []
-print("generators1 ✓")
+# generators1.py
+assert list(count_up_to(4)) == [1, 2, 3, 4], "Expected list(count_up_to(4)) to be [1, 2, 3, 4]"
+assert list(count_up_to(1)) == [1], "Expected list(count_up_to(1)) to be [1]"
+assert list(count_up_to(0)) == [], "Expected list(count_up_to(0)) to be [] (no elements when limit is 0)"
+print("generators1 ✓")
\ No newline at end of file
diff --git a/checks/generators/generators10.py b/checks/generators/generators10.py
index c5cabcd..8e2c955 100644
--- a/checks/generators/generators10.py
+++ b/checks/generators/generators10.py
@@ -1,7 +1,7 @@
-assert list(running_total([1, 2, 3, 4])) == [1, 3, 6, 10]
-assert list(running_total([10, -3, 7])) == [10, 7, 14]
-assert list(running_total([])) == []
-assert list(running_total([5])) == [5]
-# Works as a streaming pipeline over a generator input.
-assert list(running_total(x * x for x in range(1, 5))) == [1, 5, 14, 30]
-print("generators10 ✓")
+# generators10.py
+assert list(running_total([1, 2, 3, 4])) == [1, 3, 6, 10], "Expected list(running_total([1, 2, 3, 4])) to be [1, 3, 6, 10]"
+assert list(running_total([10, -3, 7])) == [10, 7, 14], "Expected list(running_total([10, -3, 7])) to be [10, 7, 14]"
+assert list(running_total([])) == [], "Expected list(running_total([])) to be [] (no elements to sum)"
+assert list(running_total([5])) == [5], "Expected list(running_total([5])) to be [5]"
+assert list(running_total(x * x for x in range(1, 5))) == [1, 5, 14, 30], "Expected running_total over a generator input (1, 4, 9, 16) to yield [1, 5, 14, 30]"
+print("generators10 ✓")
\ No newline at end of file
diff --git a/checks/generators/generators3.py b/checks/generators/generators3.py
index 8dc4615..94c70b9 100644
--- a/checks/generators/generators3.py
+++ b/checks/generators/generators3.py
@@ -1,4 +1,5 @@
+# generators3.py — first assert already has a message, leave it exactly as-is
 assert collected == [2, 4, 6, 8], f"expected [2, 4, 6, 8], got {collected}"
-assert list(evens_up_to(5)) == [2, 4]
-assert list(evens_up_to(1)) == []
-print("generators3 ✓")
+assert list(evens_up_to(5)) == [2, 4], "Expected list(evens_up_to(5)) to be [2, 4]"
+assert list(evens_up_to(1)) == [], "Expected list(evens_up_to(1)) to be [] (no even numbers \u2264 1)"
+print("generators3 ✓")
\ No newline at end of file
diff --git a/checks/generators/generators6.py b/checks/generators/generators6.py
index 8aabc65..4c6834f 100644
--- a/checks/generators/generators6.py
+++ b/checks/generators/generators6.py
@@ -1,8 +1,8 @@
+# generators6.py — first assert unchanged; big/1000 are plain variables, safe to echo
 assert first_ten == list(range(1, 11)), (
     f"expected [1..10], got {first_ten}"
 )
-# Confirm the generator really is infinite: pull 1000 values.
 big = list(itertools.islice(natural_numbers(), 1000))
-assert len(big) == 1000
-assert big[-1] == 1000
-print("generators6 ✓")
+assert len(big) == 1000, f"Expected 1000 values pulled from natural_numbers(), got {len(big)}"
+assert big[-1] == 1000, f"Expected the 1000th value to be 1000, got {big[-1]!r}"
+print("generators6 ✓")
\ No newline at end of file
diff --git a/checks/generators/generators7.py b/checks/generators/generators7.py
index a043998..66b0e43 100644
--- a/checks/generators/generators7.py
+++ b/checks/generators/generators7.py
@@ -1,11 +1,11 @@
+# generators7.py — first assert unchanged
 import itertools
 
 first8 = list(itertools.islice(fibonacci(), 8))
 assert first8 == [0, 1, 1, 2, 3, 5, 8, 13], (
     f"expected [0, 1, 1, 2, 3, 5, 8, 13], got {first8}"
 )
-# Confirm more terms keep coming.
 first15 = list(itertools.islice(fibonacci(), 15))
-assert len(first15) == 15
-assert first15[-1] == 377
-print("generators7 ✓")
+assert len(first15) == 15, f"Expected 15 terms from fibonacci(), got {len(first15)}"
+assert first15[-1] == 377, f"Expected the 15th Fibonacci term to be 377, got {first15[-1]!r}"
+print("generators7 ✓")
\ No newline at end of file
diff --git a/checks/generators/generators8.py b/checks/generators/generators8.py
index d1e027d..2e3e7c8 100644
--- a/checks/generators/generators8.py
+++ b/checks/generators/generators8.py
@@ -1,8 +1,8 @@
-assert list(Countdown(3)) == [3, 2, 1]
-assert list(Countdown(1)) == [1]
-assert list(Countdown(5)) == [5, 4, 3, 2, 1]
-# Should be re-iterable: a fresh iteration each time.
+# generators8.py — Countdown is the class under test, no re-invocation in messages
+assert list(Countdown(3)) == [3, 2, 1], "Expected list(Countdown(3)) to be [3, 2, 1]"
+assert list(Countdown(1)) == [1], "Expected list(Countdown(1)) to be [1]"
+assert list(Countdown(5)) == [5, 4, 3, 2, 1], "Expected list(Countdown(5)) to be [5, 4, 3, 2, 1]"
 cd = Countdown(3)
-assert list(cd) == [3, 2, 1]
-assert list(cd) == [3, 2, 1]
-print("generators8 ✓")
+assert list(cd) == [3, 2, 1], "Expected first iteration over cd to be [3, 2, 1]"
+assert list(cd) == [3, 2, 1], "Expected second iteration over cd to also be [3, 2, 1] \u2014 Countdown should be re-iterable, not exhausted after one pass"
+print("generators8 ✓")
\ No newline at end of file
diff --git a/checks/generators/generators9.py b/checks/generators/generators9.py
index 691b7eb..2f3cd9d 100644
--- a/checks/generators/generators9.py
+++ b/checks/generators/generators9.py
@@ -1,13 +1,13 @@
-assert list(Counter(4)) == [0, 1, 2, 3]
-assert list(Counter(1)) == [0]
-assert list(Counter(0)) == []
-# StopIteration must be raised at the right moment.
+# generators9.py
+assert list(Counter(4)) == [0, 1, 2, 3], "Expected list(Counter(4)) to be [0, 1, 2, 3]"
+assert list(Counter(1)) == [0], "Expected list(Counter(1)) to be [0]"
+assert list(Counter(0)) == [], "Expected list(Counter(0)) to be [] (no elements when stop is 0)"
 c = Counter(2)
-assert next(c) == 0
-assert next(c) == 1
+assert next(c) == 0, "Expected the first value from Counter(2) to be 0"
+assert next(c) == 1, "Expected the second value from Counter(2) to be 1"
 try:
     next(c)
     raise AssertionError("expected StopIteration after stop elements")
 except StopIteration:
     pass
-print("generators9 ✓")
+print("generators9 ✓")
\ No newline at end of file