Runs that go in circles end (M7.8)

Driver.run checks each turn with nisse_core.loop.circles and ends the run
as "circling" when the same calls get much the same back, one harness
correction is given again and again, or the model apologises, for
circle_repeats turns in a row (default 3). Near-identical calls (git add
a.py, b.py) and scattered apologies stay flags on the status page. A
fact in the transcript says why the run ended.

nisse-dev calls in a helper as for a stuck run, then asks the operator;
nisse-review counts a failed run and posts none of its drafts. Tuning:
tuning.driver / tuning.review circle_repeats (0 off) and circle_similar.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J5Utyfzw7gF7UhjRDEtjTk

nisse-review/src/nisse_review/build.py

@@ -138,6 +138,8 @@ def build(
             config.roles.resolve("driver"),
             cancel=cancel,
             compactor=Compactor(model, tuning.context.compaction(), oplog=oplog),
+            circle_repeats=tuning.review.circle_repeats,
+            circle_similar=tuning.review.circle_similar,
         ),
         account=account,
         gitea_url=config.gitea_url,

nisse-review/src/nisse_review/config.py

@@ -14,6 +14,7 @@ from typing import Any
 from nisse_core.config import (
     ConfigError,
     VaultConfig,
+    check_circles,
     flatten,
     llm_numbers,
     parse_tuning,
@@ -64,6 +65,10 @@ class ReviewTuning:
     ci_grace_s: float = field(default=120.0, metadata={"zero": True})
     # Reviews and reply sets before it sums up for the operator (R2).
     max_rounds: int = 4
+    # A run going in circles ends (L2): this many alike turns in a row, or
+    # one correction given this often; 0 never ends one. And how alike.
+    circle_repeats: int = field(default=3, metadata={"zero": True})
+    circle_similar: float = 0.9
 
 
 @dataclass(frozen=True)
@@ -136,6 +141,12 @@ class ReviewConfig:
         if tuning.context.safety_margin >= 1:
             errors.append("tuning.context.safety_margin: must be less than 1")
         check_tuning(tuning.context.compaction(), "tuning.context", errors)
+        check_circles(
+            tuning.review.circle_repeats,
+            tuning.review.circle_similar,
+            "tuning.review",
+            errors,
+        )
         vault = parse_vault(tree.get("vault"), errors)
         flat = flatten({k: v for k, v in tree.items() if k != "vault"})
         flat.pop("tuning", None)

nisse-review/tests/test_review.py

@@ -492,6 +492,29 @@ def test_the_ci_waits_may_be_zero(tmp_path: Path) -> None:
     }
     review = ReviewConfig.from_tree(tree, {}).tuning.review
     assert (review.ci_wait_s, review.ci_grace_s) == (0, 0)
+    assert (review.circle_repeats, review.circle_similar) == (3, 0.9)
+
+
+def test_circles_are_tuned_in_the_config(tmp_path: Path) -> None:
+    from nisse_core.config import ConfigError
+    from nisse_review.config import ReviewConfig
+
+    tree = {
+        "state_db": str(tmp_path / "s.db"),
+        "llm": {"base_url": "http://llm", "token": "k"},
+        "roles": {"reviewer": "local", "expert": "frontier"},
+        "gitea": {"url": "https://g", "token": "t", "operators": ["don"]},
+    }
+    off = {**tree, "tuning": {"review": {"circle_repeats": 0}}}
+    assert ReviewConfig.from_tree(off, {}).tuning.review.circle_repeats == 0
+    for bad, message in (
+        ({"circle_repeats": 1}, "circle_repeats: must be 0 (off) or 2 or more"),
+        ({"circle_similar": 1.5}, "circle_similar: must be at most 1"),
+    ):
+        with pytest.raises(
+            ConfigError, match=message.replace("(", r"\(").replace(")", r"\)")
+        ):
+            ReviewConfig.from_tree({**tree, "tuning": {"review": bad}}, {})
 
 
 def test_compaction_is_tuned_in_the_config(tmp_path: Path) -> None:
@@ -627,6 +650,20 @@ def test_out_of_turns_with_nothing_drafted_is_a_failed_run(tmp_path: Path) -> No
     assert (item(w).position, pr_of(item(w)).attempts) == (READY, 1)
 
 
+def test_a_run_going_in_circles_fails_and_its_repeats_are_not_posted(
+    tmp_path: Path,
+) -> None:
+    # L2, M7.8: the same comment drafted again and again ends the run as
+    # circling, a failed run; its drafts are the repeats, so none is posted.
+    again = [call("comment", path="count.py", line="2", text="Same point.")]
+    model = Scripted(again, again, again, again, again)
+    w = world(tmp_path, model, attempts=2)
+    w["scheduler"].round()
+    assert w["gitea"].posted == []
+    assert (item(w).position, pr_of(item(w)).attempts) == (READY, 1)
+    assert len(model.seen) == 3  # ended at the third, not at the cap
+
+
 def test_code_git_cannot_give_fails_the_run(tmp_path: Path) -> None:
     from nisse_review.clones import CloneError