AGENTS.md

@@ -304,8 +304,8 @@ the file.
 - The drain's wait on the application ignores `shutdownTimeout: 0`.
 - What the application holds unanswered is capped on constants, and a message past the cap is
   refused.
-- A store at its bound answers `ESME_RTHROTTLED` to a `submit_sm` and `ESME_RX_T_APPN` to a
+- A store at its bound answers `ESME_RTHROTTLED` to a submission and `ESME_RX_T_APPN` to a delivery,
-  `deliver_sm`.
+  a `data_sm` by whichever it stands in for.
 - A reconnect keeps the delivery-receipt merges; everything else the link held is dropped.
 - A message id base is merged at most once.
 - A send that never reached the socket waits for the next link; one that did is counted, not resent.

CHANGELOG.md

@@ -42,7 +42,7 @@
   the cap is lost, since its segments were already answered.
 - A message arriving while the application holds 1000 unanswered, or 64 MiB of them counted the way
   `maxOctets` counts segments, is refused with `ESME_RTHROTTLED` (`ESME_RX_T_APPN` on a
-  `deliver_sm`), so the peer keeps it and retries. **Call `sendResp()` on every `sms`, multipart
+  delivery), so the peer keeps it and retries. **Call `sendResp()` on every `sms`, multipart
   included**: 1000 left unanswered now stop inbound traffic for up to five minutes, where the oldest
   used to be dropped with a warning.
 - A `submit_sm` segment the reassembly buffer has no room for is refused with `ESME_RTHROTTLED`,

README.md

@@ -432,13 +432,12 @@ const { err, pduObj } = await session.send({
   each is two messages.
 - **Answered on arrival.** Each segment was answered as it landed, before you see the message:
   [Server in depth](#server-in-depth).
-- **Unanswered messages.** While 1000 messages you have not called `sendResp()` on, or 64 MiB of
+- **Unanswered messages.** While a session holds 1000 messages you have not called `sendResp()` on,
-  them counted the way `maxOctets` counts segments, are held, every new message is refused with
+  or 64 MiB of them counted the way `maxOctets` counts segments, every new message and segment is
-  `ESME_RTHROTTLED` (`ESME_RX_T_APPN` on a `deliver_sm`) so the peer retries it, and no `sms` fires.
+  refused so the peer retries it: `ESME_RTHROTTLED` on a submission, `ESME_RX_T_APPN` on a delivery.
-  Reaching the bound logs one `warn`, and the first message accepted once both are down to half one
+  No `sms` fires. Reaching the bound logs one `warn`, and the first message accepted once both are
-  `info`. A message left five
+  down to half one `info`. A message left five minutes is dropped from the count with a `warn`; a
-  minutes is dropped from the count with a `warn`; a later `sendResp()` still answers it. Neither
+  later `sendResp()` still answers it. None of the three is an option.
-  bound is an option.
 - **Where the body is.** A body in the `message_payload` TLV, SMPP's way of carrying up to 64 KB and
   the only place a `data_sm` has, reads exactly like one in `short_message`, concatenated messages
   and receipts included. A PDU filling both is read from `short_message`.

docs/decisions.md

@@ -679,25 +679,25 @@ rule and an index of the titles below.
 
 - **What the application holds unanswered is capped on constants, and a message past the cap is
   refused.** A bound the application cannot raise is the point: an application that answers nothing
-  would otherwise grow it for the life of the link, which goal 4 forbids. Reassembly's `maxOctets`
+  would otherwise hold ever more messages, which goal 4 forbids. Reassembly's `maxOctets` is an
-  is an option because it bounds what the peer sends; this bounds what the application leaves
+  option because it bounds what the peer sends; this bounds what the application leaves unanswered.
-  unanswered. Maintainer's call, 2026-09-26: a message arriving past the cap is refused with the
+  Maintainer's call, 2026-09-26. Refusing leaves the message with the peer, which will send it again
-  retry status, so the peer keeps it (goal 2). Rejected: dropping the oldest to make room, which
+  (goal 2). Rejected: dropping the oldest to make room, which frees nothing while the application
-  frees nothing while the application still holds its `Sms`, and stops the drain waiting for a
+  still holds its `Sms`, and stops the drain waiting for a message the peer is owed. Rejected:
-  message the peer is owed. Rejected: pausing the socket, which also stalls every answer and
+  pausing the socket, which also stalls every answer and `enquire_link` on the link. Reaching the
-  `enquire_link` on the link. Reaching the bound is a log line and nothing more (goal 8): an event
+  bound shows only in the log (goal 8): an event or a public count would be surface for what the
-  or a public count would be surface for what the application already knows, since it is the one
+  application already knows, since it is the one not answering. A message held past its timeout is
-  not answering. A message held past its timeout is still dropped, so `close()` can
+  still dropped, so `close()` can report fewer unanswered than there were — accepted, because the
-  report fewer unanswered than there were — accepted, because the alternative is holding what
+  alternative is holding what nothing will answer.
-  nothing will answer.
 
-- **A store at its bound answers `ESME_RTHROTTLED` to a `submit_sm` and `ESME_RX_T_APPN` to a
+- **A store at its bound answers `ESME_RTHROTTLED` to a submission and `ESME_RX_T_APPN` to a
-  `deliver_sm`.** Maintainer's call, 2026-09-26, for reassembly and held messages alike, so "keep it
+  delivery, a `data_sm` by whichever it stands in for.** Maintainer's call, 2026-09-26, for
-  and retry" has one spelling per direction. `ESME_RTHROTTLED` asks the sender to slow down, which
+  reassembly and held messages alike, so "keep it and retry" has one spelling per direction.
-  is what the peer outrunning us needs, and operators send it (Vonage, LINK Mobility, Route Mobile,
+  `ESME_RTHROTTLED` asks the sender to slow down, which is what the peer outrunning us needs, and
-  Jasmin), so clients built against them meet it (goal 1). Rejected: `ESME_RMSGQFUL`, which names an
+  operators send it (Vonage, LINK Mobility, Route Mobile, Jasmin), so clients built against them
-  exhausted queue and no rate. `ESME_RTHROTTLED` is the SMSC's to send, so an ESME answers with
+  meet it (goal 1). Rejected: `ESME_RMSGQFUL`, which names an exhausted queue and no rate.
-  SMPP 3.4's temporary receiver error, the one an SMSC retries on (goal 3).
+  `ESME_RTHROTTLED` is the SMSC's to send, so an ESME answers with SMPP 3.4's temporary receiver
+  error, the one an SMSC retries on (goal 3).
 
 - **A reconnect keeps the delivery-receipt merges; everything else the link held is dropped.**
   `onDelivery()` answers each receipt before the group it belongs to is complete, and `teardown()`

src/incoming-requests.ts

@@ -19,7 +19,7 @@ import { paramText } from './defs/types.ts';
 import { respIdParams, segmentId } from './sms-id.ts';
 import { respNameFor } from './defs/commands.ts';
 
-/** Asks the peer to keep the message and retry: RTHROTTLED is the SMSC's to send, so an ESME's is another. */
+/** Asks the peer to keep the message and retry. */
 function throttledStatus(carriedAs: string): ErrorName {
 	return carriedAs === 'submit_sm' ? 'ESME_RTHROTTLED' : 'ESME_RX_T_APPN';
 }