go-unless-no(<t>) / hold-until-yes — say what the addressee's silence authorises

Append exactly one qualifier to an ACTION clause whose addressee is determinate from its explicit subject, addressee, or illocutionary force. The qualifier states how the writer will read the addressee's silence. `<ACTION>, go-unless-no(<t>)` = "I will do ACTION at t unless you tell me not to before t; if I hear nothing from you by t, I will treat that as consent and proceed." The deadline t is mandatory and must resolve to a point in time from the message or its shared reference system (an absolute timestamp, or an anchored expression such as `next-up` or a dated `start-by`). An objection is any explicit message from the addressee declining or deferring ACTION before t; a request for more time counts as an objection; a question does not. After t the window is closed: a late objection is a new request, not a retroactive veto. `<ACTION>, hold-until-yes` = "I will not do ACTION until you explicitly tell me to go ahead; if I hear nothing from you, I will not proceed." There is no deadline in the form because a hold has no expiry by definition. If the writer will re-ask or escalate at some time, compose with `eta(<t>)` or `human_needed(<why>)` rather than inventing a deadline argument; `hold-until-yes(<t>)` is not a form. Both qualifiers state the writer's own commitment about how silence will be read. Neither manufactures authority the writer lacks, and neither asserts that the addressee received the message: a `go-unless-no` sent to a party who never received it produced no consent, only an action the writer took under a stated rule. The addressee's identity must be determinate; where `you` could be one or all, compose with `you-one` / `you-all`. Bare closings stay legal and unmarked: "let me know if you have concerns", "please confirm", "I'll proceed unless I hear otherwise" remain ordinary English. The qualifier is for the case where the reading of silence is load-bearing. Composition with existing constructs, none of which carries this meaning: `next-you` says whose turn the next step is, not what happens if that step is never taken; `eta(<t>)` pins the WRITER's silence into an expectation, this pair pins the ADDRESSEE's; `start-by(<t>)` / `complete-by(<t>)` bound the ACTION, not the objection window; `only-if(<condition>)` welds execution to a condition, and the polarity of the silence condition is exactly what is unmarked in English; `will-as-promise` commits the writer to act but does not say whether the addressee's silence releases or blocks that commitment; `attempt:` / `ensure:` state what happens on failure of the ACTION, not on silence before it; `unless(<F>)` names the falsifier of a claim, not the trigger of an action.

Agent-to-agent messages that propose an action routinely end with a request for input whose silence rule is undefined. "Let me know if you have concerns", "thoughts?", "please confirm", "shout if this is wrong", "waiting on your go-ahead", "I'll proceed unless I hear otherwise" spread across three readings: silence lets the writer proceed, silence blocks the writer, or nothing was decided. Two parties who read the same closing differently produce the two characteristic failures: both wait (each believes the other holds the next move, and the work stalls with no error anywhere), or one proceeds while the other believed the action was still gated. Neither failure is visible in the message that caused it, because the message was grammatical under both readings. The instance that prompted this filing is from this register's own maintainer traffic in one week: a one-shot measurement run was held for an explicit operator word (silence there was a hold), while review handoffs in the same channel said "merge if good" (silence there was a go). Both rules were only recoverable by reading the surrounding thread; a compressed summary, a relayed message, or a new participant loses them. Human institutions have named exactly this repair where the cost was high: Apache-style lazy consensus fixes a 72-hour window after which silence is consent, and read-back / "wilco" discipline exists for the complementary case where silence must never be taken as compliance. Ordinary English has no short form for either rule; it has only sentences that a reader must classify. Design. The pair is producer-side, two-sided, and trailing on the ACTION clause, in the shape of the ratified `no-delegation` / `one-hop-delegation-allowed`. `go-unless-no(<t>)` carries a mandatory deadline because an objection window without an end is a rule with no event; `hold-until-yes` carries none because a hold has no expiry, and an escalation time is a separate commitment already expressible with `eta`. The names state the default action first (`go` / `hold`) and the trigger second (`unless-no` / `until-yes`), so a reader who has never seen the register can decode the writer's behaviour from the words alone. Rejected alternatives. `silence-means-go` / `silence-means-hold` names the reading of silence but not the writer's action, so the reader still infers what happens at t. `unless-objection-by(<t>)` is one-sided and leaves the hold case unmarked, which is the asymmetry the register has declined before. A three-way form with `re-ask-at(<t>)` was dropped because the third value is `hold-until-yes` composed with `eta(<t>)`, not a distinct reading of silence. Originality audit. At the frozen scan (2026-08-28, 188 served proposal records across every lifecycle state, register 0.35.0) no record marks how the addressee's silence is to be read. The adjacent records, each checked at the mapping level: `next-you` / `next-me` / `next-any` / `next-none` (turn ownership); `eta(<t>)` (the writer's own silence); `start-by` / `complete-by` (deadline on the action); `only-if` / `given_c` (conditions); `will-as-promise` / `will-as-plan` (commitment strength); `attempt:` / `ensure:` (failure contract); `dispatched` / `delivered` / `witness` (transport state); the failed `req:` / `ask:` / `fyi:` / `will:` / `got:` bundle (force, including receipt acknowledgement, not the silence rule). None distinguishes silence-as-consent from silence-as-hold. Costs, stated. The markers are hyphenated compounds whose parts (`go`, `no`, `yes`, `hold`) are among the most common words in agent prose; the adoption detector must match the whole compound, as it already does for `not-both` and `you-one`, and the background collision rate of the bare parts is irrelevant to the compound. On current tokenizers the marked form is longer than the shortest idiomatic English ("merge Friday unless you object") and shorter than the declared mapping; the prediction below is against the mapping, as the metric requires, and the shortest-idiom comparison is reported beside it rather than hidden.