diff --git a/docs/plans/v2/README.md b/docs/plans/v2/README.md
index d6b0ef1..5194a88 100644
--- a/docs/plans/v2/README.md
+++ b/docs/plans/v2/README.md
@@ -77,3 +77,8 @@ reason.
   (`/home/kyle/src/crossar/Makefile`), the sandbox refused the out-of-repository read, and it
   ended its turn — the sixth refusal-ending tonight, this one triggered by its own typo. Model
   fault; no change to the task. Restarted.
+- 2026-09-25, task 05, second session (30 min in, wiring written, smoke check 3 failing): the given
+  `tools/smoke.sh` passed a 300 KB prompt as one `curl -d` argument, which Linux caps at 128 KiB
+  per argv element, so check 3 could never pass. Test fault (mine): the body now goes through a
+  file (`-d @file`). Ornith diagnosed it correctly. Resumed from the working tree with the
+  corrected script.
diff --git a/docs/plans/v2/_files/tools/smoke.sh b/docs/plans/v2/_files/tools/smoke.sh
index 965deb9..420d546 100755
--- a/docs/plans/v2/_files/tools/smoke.sh
+++ b/docs/plans/v2/_files/tools/smoke.sh
@@ -33,7 +33,9 @@ curl -s "$base/_crossbar/hosts" | grep -q '"beta":{"healthy":true' || fail "beta
 
 # 3. with beta awake, a prompt that fits nowhere is a 400 (both slots too small? no — beta fits):
 #    check the guard's refusal with a prompt beyond beta's 65536-per-slot too
-h=$(curl -s -o "$tmp/toolarge.json" -w '%{http_code}' -X POST -H 'Content-Type: application/json' -d "$(printf '{"model":"ornith-1.5-35b-a3b","messages":[{"role":"user","content":"%s"}]}' "$(head -c 300000 /dev/zero | tr '\0' 'x')")" "$base/opencode-a/v1/chat/completions")
+#    (the body goes through a file: a 300 KB string cannot be a single argv element on Linux)
+{ printf '{"model":"ornith-1.5-35b-a3b","messages":[{"role":"user","content":"'; head -c 300000 /dev/zero | tr '\0' 'x'; printf '"}]}'; } > "$tmp/toolarge-req.json"
+h=$(curl -s -o "$tmp/toolarge.json" -w '%{http_code}' -X POST -H 'Content-Type: application/json' -d @"$tmp/toolarge-req.json" "$base/opencode-a/v1/chat/completions")
 [ "$h" = "400" ] && grep -q '"prompt too large"' "$tmp/toolarge.json" || fail "300 KB prompt should be 400 prompt too large, got $h $(cat "$tmp/toolarge.json")"
 
 # 4. identity: hermes-x is locked to peer talos (header mode)