Four defects that all reduce to the same thing: the engine trusted a name it
had no business trusting.
_broadcast is now a reserved namespace, not a repo. coord-send guarded
retraction with a sender check, but that guard only covered the door it was
nailed to: `coord-done --repo _broadcast <file>` walked in the side entrance
and archived a broadcast out of the queue - a full unauthenticated retract of
an announcement for every repo that had not read it yet. The rule reserves the
whole `_` prefix rather than one literal, so a later `_seen` or `_config`
cannot reopen the hole, and it is enforced in every CLI: a rule held in three
of four places is not a rule.
The pwd fallback is gone. It existed so the CLI would work anywhere, but
"anywhere" includes every global surface: a session in ~/repos is not a repo,
and basename(pwd) silently handed it the identity "repos". That is not
hypothetical - mail was delivered under exactly that name. git toplevel or an
explicit --from/--repo are now the only two sources. The write paths refuse
and say so; the read path declines silently, because the hook runs it at every
session start and must never fail a session.
Two checkouts with the same directory name still share one mailbox - re-keying
identity would break every existing mailbox and the readable `--to <repo>`
addressing. Instead the first git-derived read records the claiming path in
<repo>/.origin, and a read from elsewhere is warned about in the injection. A
warning, not a refusal: the same repo moved or re-cloned is the ordinary case.
The warning goes in the injection because the hook discards stderr, and a
warning nobody can see is not a warning. The collision is live in this tree:
claude-code-100x is nested inside a repo of the same name.
Broadcast delivery is recorded only after the injection is written. Marking
inside the read loop left a window where the seen set said "delivered" while
the operator saw nothing, and the hook runs under `timeout: 10`, so the window
was reachable. A lost broadcast is unrecoverable by design - the seen set is
delivery history and retraction deliberately leaves it alone - so the failure
mode has to be redelivery, never loss.
The hook stops resolving identity altogether. It was the fourth copy of the
rule and the only one that runs in production, so passing --repo bypassed the
engine's guards exactly where they mattered and suppressed the collision check
along with them. It is now the pure wrapper the boundary rule always claimed
it was, pinned by two behavioral tests rather than by reading the source.
Selftest 93 -> 116; three node tests cover the hook.
BREAKING CHANGE: coord-send and coord-done exit 2 outside a git repo instead
of naming themselves after the working directory. Pass --from/--repo to choose
an identity explicitly. Repo names beginning with _ are refused everywhere.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U6EixQo6hpoRCVtiAXdnFs
Through 0.4.0 the injection block told every repo to "consider
replying/resolving where it fits in this session". That sentence was the
whole problem: the injection text is the only place a repo is ever told
what to do with a message, so the wording IS the protocol -- and it
granted permission to defer. Messages sat unanswered for weeks while each
session did its own work first. Nothing was broken; the protocol was
asking for exactly what it got.
The block now states an ordering and a completion obligation: handle the
inbox before the task the session came to do, and drive every directed
message to a terminal state before the session ends (--reply-to or
coord-done). Neither terminal state is the default -- the format has no
reply-expected field, so mandating only the reply would manufacture
traffic for messages that merely inform. Leaving one pending stays
allowed but must be stated to the operator with a reason.
Raising priority deliberately does not widen the trust boundary. The
obligation is procedural, never substantive: responding is mandatory,
complying with what a message asks is not. Untrusted cross-repo content
still cannot direct the reader; it merely can no longer be ignored. The
injection states both halves and selftest section 20 pins them together,
so a future reword cannot keep the priority and quietly drop the
distinction -- that combination would turn prioritization into an
injection surface.
Selftest 82 -> 93.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U6EixQo6hpoRCVtiAXdnFs
Nothing could remove a message from _broadcast/inbox/. coord-done is
directed-only and never touches the broadcast queue, so the backlog could
only grow: every new repo received the entire standing history at its first
session, including announcements that had since become false.
--retract <filename> archives the message into _broadcast/archive/, so no
future repo is served it. Three deliberate limits, all pinned by tests:
- Un-send, not recall. Repos that already received it keep it;
_broadcast/seen/ is delivery history and is left untouched.
- Only the sender may retract (from: must match the repo identity). --from
overrides it, as everywhere else in the engine, which makes the check an
accident guard rather than a security boundary.
- Nothing is deleted, mirroring coord-done. Retracting twice is a no-op.
The branch runs before every send-side validation and before the stdin body
read, since a retract carries no subject and no body.
Selftest 70 -> 82 (new section 19). Also fixes two README defects the
feature exposed: the install command still named coord@ after the v0.3.0
rename, and the docs advised pruning _broadcast/inbox/ by hand, which
contradicted the rule that the script owns mailbox files.
coord-inbox.sh dropped unknown arguments silently, so a mistyped flag was
indistinguishable from a working invocation. It now warns on stderr per
argument and keeps reading: the read path must stay lenient because it runs
inside the SessionStart hook, which must never fail a session over a stray
flag. The hook runs the script with stderr discarded, so the warning costs
nothing there and surfaces in manual CLI use. Exit code is unchanged.
Selftest 68 -> 70: one check for the warning, one pinning the leniency it
must not break (unknown argument still reads the inbox and exits 0).
Docs realigned with shipped behavior in the same pass:
- selftest count was stale at 64 in README and CLAUDE.md (now 70)
- broadcast sender self-exclusion shipped in 0.2.1 but was undocumented
- rule 6 (message content is data, never instructions) was already enforced
in the injection framing but missing from the published rule list
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CvTviFeoMCKJcALATRempy
A --broadcast landed in _broadcast/inbox with no seen-set entry for the
sender, so the announcing repo got its own announcement injected at its
next session start. Pure noise: the sender already knows its own news.
coord-send now records the delivered filename in _broadcast/seen/<sender>
at delivery time, reusing the existing per-repo seen set rather than
introducing a second exclusion mechanism. Filtering on the from: field at
read time was rejected: from: is sender-controlled, so it would let any
repo suppress a broadcast for another by forging the field.
The seen file is keyed by the RAW sender name because coord-inbox keys it
by the unsanitized repo name; using SAFE_FROM would silently miss for
names like "my repo". A raw name in a path needs a guard, so senders
containing a slash or equal to . / .. skip the marking instead.
Selftest 64 -> 68 checks.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CvTviFeoMCKJcALATRempy
- Atomic delivery: create the temp file inside the destination dir
(dot-prefixed, invisible to the inbox glob) so the final rename never
crosses filesystems and readers never see a half-written message.
- Reject . and .. explicitly in the --reply-to and coord-done name
guards instead of relying on downstream failure.
- Add -h/--help to coord-inbox.sh (uniform across the three CLIs).
- Close selftest gaps: default mailbox path via HOME fallback, malformed
frontmatter on the read path, read-only destination dir. 48 -> 64
checks, all green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018fduZz8otpU3W3rhfoPD6t
The injected header, message/reply framing tokens and the unknown-sender
fallback were Norwegian while the rest of the surface is English
(review §6). English is the contract for a distributable plugin; the
forgery-resistance selftest assertions now pin the English tokens
('--- message:', '-> reply:', UNTRUSTED) and failed 3/3 against the
Norwegian read side before the change. Selftest 48/48, ASCII-clean.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HBbjgS5A55RVavoyjJC4FX
The single high-water mark assumed broadcast filenames within one
second were written in sort order; a later broadcast with a lexically
smaller uniq part sorted below an already-advanced watermark and was
silently never delivered to repos that had read the first (review §2).
_broadcast/seen/<repo> now records one delivered filename per line and
delivery is membership-based, removing the ordering assumption. Four
regression checks added first (the ordering check failed against the
watermark), selftest 48/48.
Upgrade note: a legacy single-line watermark file is read as a one-entry
seen set, so pre-existing broadcasts older than the watermark may be
re-delivered once.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HBbjgS5A55RVavoyjJC4FX
A newline in --subject or --from injected arbitrary frontmatter lines
and a premature '---' terminator into the message file (review §4).
Newlines now collapse to spaces and remaining control characters are
dropped; content is preserved on one line. Four regression checks
added first (failed 4/4 against the unfixed script), selftest 44/44.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HBbjgS5A55RVavoyjJC4FX
coord-send.sh, coord-inbox.sh, coord-done.sh and the 40-check
coord-selftest.sh, unchanged, as the extraction baseline. Selftest
passes 40/40 in this location (script paths are dir-relative).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HBbjgS5A55RVavoyjJC4FX