Make concurrent tool result archives atomic

Author: Mantiee

rlm/v100/research_tools.py

@@ -841,16 +841,22 @@ def fetch(url: str) -> dict:
 
 def bounded_tool_result(root: Path, result: dict, limit: int = 4096) -> str:
     """Keep complete evidence on disk, exposing explicitly incomplete previews."""
-    encoded = json.dumps(result, ensure_ascii=False, sort_keys=True)
+    encoded = json.dumps(result, ensure_ascii=False, sort_keys=True, allow_nan=False)
     raw = encoded.encode("utf-8")
     if len(raw) <= limit:
         return encoded
+    from rlm.v100.common import atomic_json
+
+    ordered = json.loads(encoded)
+    raw = (json.dumps(ordered, ensure_ascii=False, indent=2, allow_nan=False) + "\n").encode(
+        "utf-8"
+    )
     digest = hashlib.sha256(raw).hexdigest()
     folder = root / "research/tool-results"
     folder.mkdir(parents=True, exist_ok=True)
     path = folder / f"{digest}.json"
     if not path.exists():
-        path.write_bytes(raw)
+        atomic_json(path, ordered)
     if hashlib.sha256(path.read_bytes()).hexdigest() != digest:
         raise ValueError("Archived tool result changed")
     return json.dumps(

tests/test_v100_research_context.py

@@ -71,3 +71,18 @@ def request(endpoint, payload):
         assert generated[0]["max_tokens"] == 128
         assert "large" not in generated[1]["messages"][-1]["content"]
     assert client.sampling_args == original
+
+
+def test_parallel_workers_archive_identical_evidence_without_partial_reads(tmp_path):
+    from concurrent.futures import ThreadPoolExecutor
+
+    result = {"rows": [{"id": i, "text": "evidence" * 300} for i in range(20)]}
+    with ThreadPoolExecutor(max_workers=6) as workers:
+        previews = list(
+            workers.map(
+                lambda _: json.loads(research_tools.bounded_tool_result(tmp_path, result, 2048)),
+                range(24),
+            )
+        )
+    assert len({row["full_result_sha256"] for row in previews}) == 1
+    assert len(list((tmp_path / "research/tool-results").glob("*.json"))) == 1