diff --git a/plugins/violin_guard/command.py b/plugins/violin_guard/command.py
index 381a46b..da9aee4 100644
--- a/plugins/violin_guard/command.py
+++ b/plugins/violin_guard/command.py
@@ -332,6 +332,60 @@ def check_local_artifact_paths(command: str) -> CheckResult:
     return result
 
 
+_HTTP_CLIENT_RE = re.compile(r"\b(?:curl|wget)\b", re.I)
+_HTTP_URL_RE = re.compile(r"https?://\S+", re.I)
+_HTTP_LONG_FLAG_RE = re.compile(
+    r"-(?:include|verbose|head|dump-header|write-out|output|remote-name|output-document)\b",
+    re.I,
+)
+# Offline captures (`-o file`, `-O`, `-e/--output`, `> file`) are not
+# interactive HTTP evidence; status probes via `-w` are separately exempted.
+_HTTP_OFFLINE_CAPTURE_RE = re.compile(
+    r"-(?:o|O|output|remote-name|output-document)\b|\s>\s*[^\s|]+", re.I
+)
+
+
+def _has_short_flag(command: str, *flags: str) -> bool:
+    """True if any single-dash short-flag cluster contains one of `flags`.
+
+    Handles combined clusters (`-si`, `-sv`, `-Dk`) and separate tokens
+    (`-s -i`). Case-sensitive on purpose: `-D` (dump-header) counts while
+    `-d` (POST data) does not. Guarded to letters-only tokens to avoid
+    matching data payloads or stray dashes.
+    """
+    wanted = set(flags)
+    return any(
+        any(ch in wanted for ch in token)
+        for token in re.findall(r"(?<!\S)-[A-Za-z]+", command)
+    )
+
+
+def check_http_proof_flags(command: str) -> CheckResult:
+    """Review-level guard: HTTP probes must capture the response status/headers.
+
+    SKILL.md §4 mandates `-i` or `-sv` when testing HTTP endpoints so evidence
+    files carry empirical status lines. Receipts from plain `curl -s` (no `-i`)
+    make `has_decisive_proof` fail and burn real confirmations at scoring time
+    (benchmark-run-20260811_175611: only 6/194 receipts carried HTTP/1.1).
+    Exempted: status probes (`-w %{http_code}`), HEAD (`-I`), header dumps
+    (`-D`), and offline captures (`-o`/`-O`/`> file`) that are not interactive
+    HTTP evidence.
+    """
+    result = CheckResult()
+    if not _HTTP_CLIENT_RE.search(command) or not _HTTP_URL_RE.search(command):
+        return result
+    if _HTTP_LONG_FLAG_RE.search(command) or _HTTP_OFFLINE_CAPTURE_RE.search(command):
+        return result
+    if _has_short_flag(command, "i", "v", "I", "D", "w", "o", "O"):
+        return result
+    result.add_warning(
+        "HTTP probe without status/headers capture: add `-i` (or `-sv`) to curl "
+        "so the evidence file records the response status line — plain `-s` "
+        "produces no HTTP/1.1 line and fails decisive-proof scoring"
+    )
+    return result
+
+
 def check_cross_engagement_paths(command: str, active_eng_dir: Path) -> CheckResult:
     """Block commands that reference a foreign engagement directory under engagements/."""
     result = CheckResult()
@@ -626,6 +680,11 @@ def check_command(args: CheckCommandArgs) -> CheckResult:
     destructive_result = check_destructive_patterns(args.command)
     result.errors.extend(destructive_result.errors)
 
+    # 2c2. HTTP proof flags (review): `-i`/`-sv` so receipts are decisive
+    proof_result = check_http_proof_flags(args.command)
+    result.warnings.extend(proof_result.warnings)
+    result.infos.extend(proof_result.infos)
+
     artifact_result = check_local_artifact_paths(args.command)
     result.infos.extend(artifact_result.infos)
 
diff --git a/tests/guard/guards/test_http_proof_flags.py b/tests/guard/guards/test_http_proof_flags.py
new file mode 100644
index 0000000..75ff00f
--- /dev/null
+++ b/tests/guard/guards/test_http_proof_flags.py
@@ -0,0 +1,54 @@
+"""HTTP proof-flag guard tests — decisiveness of curl receipts at scoring time.
+
+Regression: benchmark-run-20260811_175611 wrote 194 receipts but only 6
+carried HTTP/1.1 status lines (plain `curl -s` without `-i`), so the
+decisive-proof scorer rejected most of them. SKILL.md §4 mandates `-i`/`-sv`;
+this guard makes the requirement a review gate.
+"""
+
+from __future__ import annotations
+
+from plugins.violin_guard.command import check_http_proof_flags
+
+
+def test_plain_silent_curl_warns_review() -> None:
+    result = check_http_proof_flags(
+        "curl -s https://duck-store.escape.tech/api/v1/products"
+    )
+    assert result.errors == []
+    assert len(result.warnings) == 1
+    assert "-i" in result.warnings[0]
+    assert result.exit_code() == 2  # review, not hard block
+
+
+def test_curl_with_status_capture_is_clean() -> None:
+    for command in (
+        "curl -si https://duck-store.escape.tech/api/v1/products",
+        "curl -i -X POST https://duck-store.escape.tech/api/v1/auth/login -d '{}'",
+        "curl -sv https://duck-store.escape.tech/api/v1/orders/1",
+        "curl -I https://duck-store.escape.tech/",
+        "curl -D headers.txt https://duck-store.escape.tech/api/v1/products",
+    ):
+        result = check_http_proof_flags(command)
+        assert result.errors == [] and result.warnings == [], command
+        assert result.exit_code() == 0, command
+
+
+def test_status_probe_and_offline_capture_exempt() -> None:
+    for command in (
+        "curl -s -o /dev/null -w '%{http_code}' https://duck-store.escape.tech/api/v1/auth/login",
+        "curl -sO https://duck-store.escape.tech/bundle.js",
+        "curl -s https://duck-store.escape.tech/api/v1/products > evidence/recon/products.json",
+    ):
+        result = check_http_proof_flags(command)
+        assert result.errors == [] and result.warnings == [], command
+
+
+def test_non_http_or_non_curl_commands_untouched() -> None:
+    for command in (
+        "nmap -sV 10.10.10.10",
+        "grep -i admin evidence/recon/products.json",
+        "python3 tools/burst.py --target https://duck-store.escape.tech",
+    ):
+        result = check_http_proof_flags(command)
+        assert result.errors == [] and result.warnings == [], command