Record the TLV keying decision as the maintainer's

todo.md

@@ -78,34 +78,31 @@ Every defect listed in the AGENTS.md table has a regression test naming the beha
 `gitea.larvit.se/larvit/smpp-js` is the repository. `github.com/larvit/smpp-js` mirrors it and is the
 place issues are filed. Maintainer's calls, 2026-09-13 and 2026-09-14.
 
-- [x] **Move `main` and `v0.4.0` to `larvit/smpp-js`.** It holds `main`, from `typescript`, and
+- [x] `larvit/smpp-js` holds `main`, from `typescript`, and `v0.4.0`, from `master`. `rewrite-base`
-      `v0.4.0`, from `master`. `rewrite-base` and the `renovate/*` branches stayed behind.
+      and the `renovate/*` branches stayed behind.
-- [x] **Protect `main` with fast-forward merges and required checks.** Fast-forward is the only
+- [x] Fast-forward is the only merge style. `main` takes no pushes, requires `Test / lint
-      merge style. `main` takes no pushes, requires `Test / lint (pull_request)` and `Test / test
+      (pull_request)` and `Test / test (*) (pull_request)`, blocks an outdated branch, and gives
-      (*) (pull_request)`, blocks an outdated branch, and gives admins no override. Every other
+      admins no override. Every other branch takes force pushes.
-      branch takes force pushes.
+- [x] The workflows are in `.gitea/workflows/`. Tests run on pull requests only, the event the gate
-- [x] **Run the workflows from `.gitea/workflows/`.** Tests run on pull requests only, the event the
+      reads; Renovate runs as a scheduled workflow, as on adf-codec.
-      gate reads; Renovate runs as a scheduled workflow, as on adf-codec.
+- [x] The release publishes without provenance, which npm generates only on GitHub Actions and
-- [x] **Publish the release without provenance.** npm generates it only on GitHub Actions and GitLab
+      GitLab CI/CD.
-      CI/CD.
+- [x] `package.json` names Gitea, and the GitHub mirror's issues as `bugs`. The README links
-- [x] **Name Gitea in `package.json`, and the GitHub mirror's issues as `bugs`.** The README links
       absolutely: npmjs.com resolves a relative link against itself when the `repository` is not on
       GitHub. Its test badge is gone, since Gitea reports a workflow's status per branch and no
       workflow runs on `main`.
-- **Add a github.com token for Renovate only if its lookups hit the rate limit.**
+- `RENOVATE_GITHUB_TOKEN` exists nowhere, so Renovate queries github.com unauthenticated, as
-  `RENOVATE_GITHUB_TOKEN` exists nowhere, so Renovate queries github.com unauthenticated, as
   adf-codec's nightly run already does without a warning. `RENOVATE_TOKEN` is the Gitea token and
-  cannot stand in for it.
+  cannot stand in for it. Add a github.com token only if lookups hit the rate limit.
 
 ## Before publishing 0.5.0
 
-- [x] **Publish the rewrite as 0.5.0, not 1.0.0, while usage is this low.** Maintainer's call,
+- [x] 0.5.0 rather than 1.0.0, while usage is this low. Maintainer's call, 2026-09-14.
-      2026-09-14.
+- [x] `NPM_TOKEN`, which `.gitea/workflows/release.yaml` needs, is a Gitea organization secret.
-- [x] **Hold `NPM_TOKEN` as a Gitea organization secret.** `.gitea/workflows/release.yaml` needs it.
+- [x] Tag `v0.5.0` on Gitea to publish. The first publish creates `@larvit/smpp` on npm, provided the
-- [x] **Tag `v0.5.0` on Gitea to publish.** The first publish creates `@larvit/smpp` on npm,
+      token can publish under `@larvit`.
-      provided the token can publish under `@larvit`.
+- [x] `npm deprecate larvitsmpp` pointing at `@larvit/smpp`. Maintainer's call to run it; not
-- [x] **Deprecate `larvitsmpp` on npm, pointing at `@larvit/smpp`.** `npm deprecate larvitsmpp` is
+      something CI should do.
-      the maintainer's call to run; not something CI should do.
 
 ## Retire the GitHub repository
 
@@ -113,54 +110,52 @@ Nothing here starts before 0.5.0 is published. Maintainer's call, 2026-09-14. Th
 deleting GitHub's old branches closes every pull request based on them without a reply, and GitHub
 refuses to delete its default branch.
 
-- [x] **Close the backlog below.**
+- [x] Close the backlog below.
-- [x] **Close [#71](https://github.com/larvit/larvitsmpp/pull/71), pointing at Gitea.**
+- [x] Close [#71](https://github.com/larvit/larvitsmpp/pull/71), pointing at Gitea.
-- [x] **Rename `larvit/larvitsmpp` to `larvit/smpp-js`.** GitHub redirects the old URLs, and the
+- [x] Rename `larvit/larvitsmpp` to `larvit/smpp-js`. GitHub redirects the old URLs, and the `bugs`
-      `bugs` URL in `package.json` resolves from then on.
+      URL in `package.json` resolves from then on.
-- [x] **Push `main` and make it GitHub's default branch.**
+- [x] Push `main` and make it GitHub's default branch.
-- [x] **Set Renovate to Silent for this repository in the Mend Developer Portal.** It then opens
+- [x] Renovate is Silent for this repository in the Mend Developer Portal, so it opens nothing on
-      nothing on GitHub while the organization-wide installation stays. CodeRabbit stays installed.
+      GitHub while the organization-wide installation stays. CodeRabbit stays installed.
       Maintainer's call, 2026-09-14.
-- [x] **Mirror to GitHub from `.gitea/workflows/mirror.yaml` and `mirror-delete.yaml`, with
+- [x] Mirror to GitHub from `.gitea/workflows/mirror.yaml` and `mirror-delete.yaml`, with
-      `MIRROR_GITHUB_TOKEN`.** A push of a commit carrying the workflow, and the nightly run, send
+      `MIRROR_GITHUB_TOKEN`. A push of a commit carrying the workflow, and the nightly run, send all of
-      all of Gitea's branches and tags, overwriting a same-named ref; a branch or tag deleted on
+      Gitea's branches and tags, overwriting a same-named ref; a branch or tag deleted on Gitea is
-      Gitea is deleted there too. Refs only GitHub has stay. Maintainer's call, 2026-09-14.
+      deleted there too. Refs only GitHub has stay. Maintainer's call, 2026-09-14.
-- [x] **Strip GitHub's repository to a mirror, and give both forges the package's About.** GitHub's
+- [x] GitHub's wiki, projects and Actions are off, the Travis app and webhook are gone, and its About
-      wiki, projects and Actions are off, the Travis app and webhook are gone, and its About matches
+      matches the package. Gitea carries the same description, website and topics, and sends issues
-      the package. Gitea carries the same description, website and topics, and sends issues to
+      to GitHub as its external tracker.
-      GitHub as its external tracker.
 
 ## Close the GitHub backlog
 
 **Answer and close as fixed by 0.5.0**, the reply naming what fixed it:
 
-- [x] **Close [#2](https://github.com/larvit/larvitsmpp/issues/2), tests for the README examples.**
+- [x] [#2](https://github.com/larvit/larvitsmpp/issues/2) Tests for the README examples:
-      Fixed by `test/readme.test.ts`.
+      `test/readme.test.ts`.
-- [x] **Close [#3](https://github.com/larvit/larvitsmpp/issues/3), tests for flash messages.** Fixed
+- [x] [#3](https://github.com/larvit/larvitsmpp/issues/3) Tests for flash messages:
-      by `test/session.test.ts`.
+      `test/session.test.ts`.
-- [x] **Close [#4](https://github.com/larvit/larvitsmpp/issues/4), DLR errors with `message_state`
+- [x] [#4](https://github.com/larvit/larvitsmpp/issues/4) DLR errors with `message_state` missing:
-      missing.** `dlrFromPdu()` parses the `stat:` receipt text when the TLVs are absent.
+      `dlrFromPdu()` parses the `stat:` receipt text when the TLVs are absent.
-- [x] **Close [#13](https://github.com/larvit/larvitsmpp/issues/13), limit a long SMS to fewer
+- [x] [#13](https://github.com/larvit/larvitsmpp/issues/13) Limit a long SMS to fewer segments: the
-      segments.** Fixed by the `maxSegments` send option.
+      `maxSegments` send option.
-- [x] **Close [#16](https://github.com/larvit/larvitsmpp/issues/16), support all three bind types.**
+- [x] [#16](https://github.com/larvit/larvitsmpp/issues/16) Support all three bind types: bound and
-      Bound and enforced in both directions.
+      enforced in both directions.
-- [x] **Close [#17](https://github.com/larvit/larvitsmpp/issues/17), `addr_ton`/`addr_npi` should be
+- [x] [#17](https://github.com/larvit/larvitsmpp/issues/17) `addr_ton`/`addr_npi` should be
-      settable.** `sendSms()` takes all four, documented and tested.
+      settable: `sendSms()` takes all four, documented and tested.
-- [x] **Close [#20](https://github.com/larvit/larvitsmpp/issues/20), tests fail on current
+- [x] [#20](https://github.com/larvit/larvitsmpp/issues/20) Tests fail on current dependency
-      dependency versions.** The mocha suite is gone; `node:test` on Node 18 to 26.
+      versions: the mocha suite is gone; `node:test` on Node 18 to 26.
-- [x] **Close [#33](https://github.com/larvit/larvitsmpp/issues/33), large inbound text arrives as
+- [x] [#33](https://github.com/larvit/larvitsmpp/issues/33) Large inbound text arrives as raw
-      raw `Buffer` segments.** `IncomingRequests` reassembles a UDH-carrying `deliver_sm` into one
+      `Buffer` segments: `IncomingRequests` reassembles a UDH-carrying `deliver_sm` into one `sms`
-      `sms` event.
+      event.
-- [x] **Close [#68](https://github.com/larvit/larvitsmpp/pull/68), a pull request for `message_id`
+- [x] [#68](https://github.com/larvit/larvitsmpp/pull/68), a pull request: `message_id` in
-      in `submit_sm_resp` and spec DLR codes.** All four hold: `sendResp()` always answers a
+      `submit_sm_resp`, spec DLR codes. All four hold: `sendResp()` always answers a `message_id`,
-      `message_id`, per segment; `stat:UNDELIV` is the 7-character code. Credit the reporter — the
+      per segment; `stat:UNDELIV` is the 7-character code. Credit the reporter — the fork found real
-      fork found real defects.
+      defects.
 
 **Close as superseded**, all against 0.4.0 dependencies the rewrite does not have — `async`,
 `coveralls`, `eslint`, `iconv-lite`, `larvitutils`, `mocha`, `mocha-eslint`, `portfinder`, `uuid`:
 
-- [x] **Close the twelve dependency pull requests as superseded.**
+- [x] [#40](https://github.com/larvit/larvitsmpp/pull/40),
-      [#40](https://github.com/larvit/larvitsmpp/pull/40),
       [#41](https://github.com/larvit/larvitsmpp/pull/41),
       [#42](https://github.com/larvit/larvitsmpp/pull/42),
       [#45](https://github.com/larvit/larvitsmpp/pull/45),
@@ -180,9 +175,8 @@ the rewrite, for a dependency added later. Maintainer's call, 2026-09-14.
 
 **Close as tracked here**, the reply saying it will be implemented on Gitea:
 
-- [x] **Close [#8](https://github.com/larvit/larvitsmpp/issues/8), the socket's remote host and port
+- [x] [#8](https://github.com/larvit/larvitsmpp/issues/8) The socket's remote host and port on log
-      on log messages, as tracked here.** It sits under Worth doing, not blocking. Maintainer's
+      messages: under Worth doing, not blocking. Maintainer's call, 2026-09-14.
-      call, 2026-09-14.
 
 ## 0.6.0
 
@@ -452,80 +446,78 @@ next work ([decision](docs/decisions.md#internals-and-tests)).
       as `true`. One fix closes all three, and `valueText()` in `defs/types.ts` is the quoted
       spelling to take it from. Raised by review, 2026-09-20.
 
-- [ ] **Refuse a send the codec cannot build before it waits for a link and a window slot.** Today
+- [ ] **A send the codec will refuse waits for a link and a window slot first.** `refuse()` in
-      it waits first. `refuse()` in `outgoing-requests.ts` runs `misuse()` and the abort check
+      `outgoing-requests.ts` runs `misuse()` and the abort check before the wait, precisely so a call
-      before the wait, precisely so a call that can never go out does not queue for what it will
+      that can never go out does not queue for what it will never use; a body `objToPdu()` refuses on
-      never use; a body `objToPdu()` refuses on every attempt is the same case, and #98 made it a
+      every attempt is the same case, and #98 made it a common one. On a down link the caller waits
-      common one. On a down link the caller waits `responseTimeout` and is told the link failed
+      `responseTimeout` and is told the link failed rather than that the body could not be built —
-      rather than that the body could not be built — goal 2's wrong answer about what happened. The
+      goal 2's wrong answer about what happened. The cheap fix builds the PDU twice, so the shape is
-      cheap fix builds the PDU twice, so the shape is the open half. Raised by the architecture
+      the open half. Raised by the architecture review of
-      review of [#98](https://github.com/larvit/larvitsmpp/pull/98), 2026-09-09.
-
-- [ ] **Split the SMPP time format out of `message.ts` once the file has to move anyway.** It
-      answers two questions: message coding and the SMPP time format (`smppDate`, `smppTime`) share
-      the file, which the architecture map in AGENTS.md already spells out as four concerns. Nothing
-      is wrong today; if the file has to move for another reason, `smpp-time.ts` is the split.
-      Raised by the architecture review of
       [#98](https://github.com/larvit/larvitsmpp/pull/98), 2026-09-09.
 
-- [ ] **Add a gate that refuses a floating version anywhere in the repo.** Maintainer's ask on
+- [ ] **`message.ts` answers two questions.** Message coding and the SMPP time format (`smppDate`,
-      [#71](https://github.com/larvit/larvitsmpp/pull/71), 2026-09-06, on the `release.yaml` pinning
+      `smppTime`) share the file, which the architecture map in AGENTS.md already spells out as four
-      thread. Pinning every action and runner by hand is what the ask followed; the gate is what
+      concerns. Nothing is wrong today; if the file has to move for another reason, `smpp-time.ts` is
-      keeps them pinned. It has to cover workflow `uses:` and `runs-on:`, compose `image:`, and
+      the split. Raised by the architecture review of
+      [#98](https://github.com/larvit/larvitsmpp/pull/98), 2026-09-09.
+
+- [ ] **A gate that refuses a floating version anywhere in the repo.** Maintainer's ask on
+      [#71](https://github.com/larvit/larvitsmpp/pull/71), 2026-09-06, on the `release.yaml`
+      pinning thread. Pinning every action and runner by hand is what the ask followed; the gate is
+      what keeps them pinned. It has to cover workflow `uses:` and `runs-on:`, compose `image:`, and
       Dockerfile `FROM`, and the conventions differ per kind — actions take a semver tag, images the
       full patch version — so one grep for `latest` is not it.
 
-- [ ] **Add a gate that catches the test matrix missing the current Node.** Maintainer's ask on
+- [ ] **A gate that fails when the test matrix misses the current Node.** Maintainer's ask on
       [#71](https://github.com/larvit/larvitsmpp/pull/71), 2026-09-06, on the Node 26 thread. Node
       26 was added by hand; nothing notices when 27 ships. Needs a source for what Current is — the
       Node release schedule is published as JSON — and a decision on whether a new Current fails the
       build or opens a PR, which is what Renovate already does for everything else here.
 
-- [ ] **Have CodeRabbit review Gitea pull requests through the GitHub mirror.** CodeRabbit does not
+- [ ] **CodeRabbit reviews through the GitHub mirror.** CodeRabbit does not support Gitea, so mirror
-      support Gitea, so mirror each Gitea pull request to GitHub for it to review there.
+      each Gitea pull request to GitHub for it to review there. Maintainer's ask, 2026-09-14; not
-      Maintainer's ask, 2026-09-14; not started until asked.
+      started until asked.
 
-- [ ] **Count what is left of a budget one way in `leftOf()` and the link gate.** Today they are one
+- [ ] **`leftOf()` and the link gate's own budget are one concept counted twice.**
-      concept counted twice. `idle-waiters.ts` reads what is left of a budget as `Math.max(1,
+      `idle-waiters.ts` reads what is left of a budget as `Math.max(1, deadline - now)`, because 0
-      deadline - now)`, because 0 means "forever" there; `link-gate.ts` runs the same subtraction
+      means "forever" there; `link-gate.ts` runs the same subtraction and calls `<= 0` expired.
-      and calls `<= 0` expired. Neither is reachable from the other, so nothing can disagree today,
+      Neither is reachable from the other, so nothing can disagree today, but a reader who learns one
-      but a reader who learns one and applies it to the other is wrong. A budget type both take
+      and applies it to the other is wrong. A budget type both take would close it. Raised by review,
-      would close it. Raised by review, 2026-09-01.
+      2026-09-01.
 
-- [ ] **Write a non-zero `err:` on a receipt only for a state that failed.** `receiptText()` now
+- [ ] **`err:` on a receipt for a state that neither delivered nor failed.** `receiptText()` now
       writes `err:000` for `DELIVERED` and for the two transient states, and `err:001` for every
-      other — so `ACCEPTED`, `SKIPPED`, `UNKNOWN` and `DELETED` still announce an error code the
+      other — so `ACCEPTED`, `SKIPPED`, `UNKNOWN` and `DELETED` still announce an error code the SMSC
-      SMSC never had. Which of those are failures is the open half. Raised by review, 2026-09-03;
+      never had. Which of those are failures is the open half. Raised by review, 2026-09-03; needs a
-      needs a decision.
+      decision.
 
-- [ ] **Share one `once()` across the test files, one that gives up.** Today it is copied into four
+- [ ] **`once()` is copied into four test files, and two copies never give up.**
-      test files, and two copies never give up. `session-extras.test.ts` and `readme.test.ts` reject
+      `session-extras.test.ts` and `readme.test.ts` reject after 5000 ms; `session.test.ts` and
-      after 5000 ms; `session.test.ts` and `tls.test.ts` wait forever, so an event that never fires
+      `tls.test.ts` wait forever, so an event that never fires still hangs the run the way an
-      still hangs the run the way an unclosed listener used to. One shared, guarded copy closes the
+      unclosed listener used to. One shared, guarded copy closes the rest of that class.
-      rest of that class.
 
-- [ ] **Carry the peer's address and bind on every session log message.** `remoteAddress` and
+- [ ] **The peer's address and bind on every session log message.** `remoteAddress` and `remotePort`
-      `remotePort` reach only `server - incoming connection`, and `systemId` only the bind messages,
+      reach only `server - incoming connection`, and `systemId` only the bind messages, so with
-      so with several peers connected one session's lines cannot be told apart, and a reconnect
+      several peers connected one session's lines cannot be told apart, and a reconnect leaves nothing
-      leaves nothing stable to filter on. Carrying them in every session message's metadata is a
+      stable to filter on. Carrying them in every session message's metadata is a change to every
-      change to every call site. From [#8](https://github.com/larvit/larvitsmpp/issues/8), closed
+      call site. From [#8](https://github.com/larvit/larvitsmpp/issues/8), closed there as tracked
-      there as tracked here; maintainer's call, 2026-09-14.
+      here; maintainer's call, 2026-09-14.
 
-- [ ] **Settle how a peer whose message ids share one base logs its refused merges.** Today it logs
+- [ ] **A peer whose message ids share one base logs a refused merge on every send.** `smsc01-000123`
-      one on every send. `smsc01-000123` and `smsc01-000124` carry the same base, so `DlrMerger`
+      and `smsc01-000124` carry the same base, so `DlrMerger` merges the first message and refuses
-      merges the first message and refuses every one after it, one log line per send. Left at `info`
+      every one after it, one log line per send. Left at `info` — nothing the operator can fix is
-      — nothing the operator can fix is wrong — but a rate guard or silence may suit it better.
+      wrong — but a rate guard or silence may suit it better. Raised by review, 2026-08-30.
-      Raised by review, 2026-08-30.
 
-- [ ] **Exercise `submit_multi` and the broadcast commands end to end.** They encode and decode, but
+- [ ] **`submit_multi` and the broadcast commands** encode and decode, but nothing exercises them
-      nothing exercises them end to end. The interop suite is the natural place.
+      end to end. The interop suite is the natural place.
-- [ ] **Move to TypeScript 7 once `typescript-eslint` supports it.** `renovate.json` pins TypeScript
+- [ ] **Move to TypeScript 7** once `typescript-eslint` supports it; `renovate.json` pins TypeScript
       below 6.1 for exactly that reason.
-- [ ] **Add an `onReceipt` hook.** Receipt text is only loosely specified and operators disagree on
+- [ ] **An `onReceipt` hook.** Receipt text is only loosely specified and operators disagree on it,
-      it, but `dlrFromPdu()` is wired into `IncomingRequests` with no seam of its own: an
+      but `dlrFromPdu()` is wired into `IncomingRequests` with no seam of its own: an application
-      application facing a format we do not parse has to take the whole PDU on `onRequest` and
+      facing a format we do not parse has to take the whole PDU on `onRequest` and reimplement the
-      reimplement the dispatch, which owns the response as well. Mirror the `onRequest` seam —
+      dispatch, which owns the response as well.
-      return a `Dlr` to own the receipt, `undefined` to fall through to the built-in parser.
+      Mirror the `onRequest` seam — return a `Dlr` to own the receipt, `undefined` to fall through
+      to the built-in parser.
 
 ## Gaps against other SMPP libraries
 
@@ -535,40 +527,38 @@ Each lands under goal 7: an option or a hook, with the call that passes none unc
 
 ### Sending
 
-- [ ] **Add a limiter hook, with a messages-per-second cap built on it.** Maintainer's call,
+- [ ] **A limiter hook, with a messages-per-second cap built on it.** Maintainer's call, 2026-09-14,
-      2026-09-14, reversing the earlier decline: Kannel, Jasmin, go-smpp and `smpp-js-sdk` all limit
+      reversing the earlier decline: Kannel, Jasmin, go-smpp and `smpp-js-sdk` all limit throughput.
-      throughput. Count PDUs, not `sendSms()` calls — a long message is one `submit_sm` per segment
+      Count PDUs, not `sendSms()` calls — a long message is one `submit_sm` per segment and the
-      and the operator counts those, which an application wrapping `sendSms()` cannot see. The hook
+      operator counts those, which an application wrapping `sendSms()` cannot see. The hook takes a
-      takes a limiter the application already runs; the built-in cap counts per session until the
+      limiter the application already runs; the built-in cap counts per session until the store at the
-      store at the bottom lets it span sessions and processes. The default stays uncapped. Open: the
+      bottom lets it span sessions and processes. The default stays uncapped. Open: the hook's shape (a
-      hook's shape (a wait that resolves when a PDU may go, cut short by the send's `signal`), which
+      wait that resolves when a PDU may go, cut short by the send's `signal`), which requests it gates
-      requests it gates — messages, never `enquire_link`, `unbind` or a response — and whether its
+      — messages, never `enquire_link`, `unbind` or a response — and whether its wait counts against
-      wait counts against `responseTimeout`.
+      `responseTimeout`.
 
 - [ ] **Back off and resend on `ESME_RTHROTTLED`.** The SMSC refused the PDU, so resending cannot
       duplicate it and goal 2 holds, and the retry needs nothing wider than the session. Needs a
       decision: on by default with a bounded budget, as goal 5 suggests, and whether `ESME_RMSGQFUL`
       counts too. A throttled answer is also what a limiter hook wants to hear about.
 
-- [ ] **Let `sendSms()` take the rest of `submit_sm`.** `service_type`, `priority_flag`,
+- [ ] **`sendSms()` takes the rest of `submit_sm`.** `service_type`, `priority_flag`, `protocol_id`,
-      `protocol_id`, `replace_if_present_flag` and TLVs on every segment, and `registered_delivery`
+      `replace_if_present_flag` and TLVs on every segment, and `registered_delivery` beyond final
-      beyond final receipts: on failure only, and intermediate notifications. Today each needs
+      receipts: on failure only, and intermediate notifications. Today each needs `send()`, which gives
-      `send()`, which gives up splitting, the alphabet checks and receipt merging. TLVs are the
+      up splitting, the alphabet checks and receipt merging. TLVs are the common case: India's DLT
-      common case: India's DLT rules put `PE_ID` (0x1400) and `TEMPLATE_ID` (0x1401) on every
+      rules put `PE_ID` (0x1400) and `TEMPLATE_ID` (0x1401) on every `submit_sm`, and USSD rides on
-      `submit_sm`, and USSD rides on `ussd_service_op`. Refuse a TLV the send composes itself
+      `ussd_service_op`. Refuse a TLV the send composes itself (`sar_*`, `message_payload`). Open: one
-      (`sar_*`, `message_payload`). Open: one spelling for receipts, since `dlr: true` and a raw
+      spelling for receipts, since `dlr: true` and a raw `registered_delivery` could disagree, and
-      `registered_delivery` could disagree, and whether goal 4's rule on optional parameters binds a
+      whether goal 4's rule on optional parameters binds a TLV the caller named.
-      TLV the caller named.
 
 - [ ] **Choose how a long message is spelled on the wire.** Only an 8-bit UDH reference goes out
       (`message.ts`), though the reader takes a 16-bit UDH, `sar_*` and `message_payload` alike. Some
       SMSCs take only `sar_*` or `message_payload`; php-smpp offers all three. A 16-bit reference also
       makes a collision rarer: the 8-bit one wraps every 255 sends on a session.
 
-- [ ] **Fail over across SMSC hosts.** Maintainer's call, 2026-09-14. `client()` takes one `host`
+- [ ] **Failover across SMSC hosts.** Maintainer's call, 2026-09-14. `client()` takes one `host` and
-      and `port`; Kannel, Jasmin and php-smpp take several. A list the reconnect loop walks holds
+      `port`; Kannel, Jasmin and php-smpp take several. A list the reconnect loop walks holds only
-      only which host the one session is on, so it needs no store. Two options, both maintainer's
+      which host the one session is on, so it needs no store. Two options, both maintainer's calls:
-      calls:
       - **Order**, `fixed` or round robin, default `fixed`. Fixed starts every reconnect at the first
         host; round robin at the host after the one the link was last on.
       - **Starting over**, a boolean, default on: once the last host has been tried, go back to the
@@ -579,29 +569,26 @@ Each lands under goal 7: an option or a hook, with the call that passes none unc
 
 ### The server
 
-- [ ] **Send `deliver_sm` from `sendSms()` on a `server()` session.** Today it sends `submit_sm`
+- [ ] **`sendSms()` on a `server()` session sends `submit_sm` toward the ESME.** Kannel answers
-      toward the ESME. Kannel answers `ESME_RINVCMDID` (`interop-tests/kannel.test.ts`, "MO to
+      `ESME_RINVCMDID` (`interop-tests/kannel.test.ts`, "MO to Kannel"), and goal 1 says that PDU never
-      Kannel"), and goal 1 says that PDU never goes out. A server has no other way to send an MO
+      goes out. A server has no other way to send an MO message either: `sendMo()` in that test builds
-      message either: `sendMo()` in that test builds one from `submitSmParams()` and
+      one from `submitSmParams()` and `ConcatReference`, neither exported. Choosing `deliver_sm` by
-      `ConcatReference`, neither exported. Choosing `deliver_sm` by `linkEnd` gives MO messages the
+      `linkEnd` gives MO messages the splitting and checks, keeps one method for one goal, and refuses
-      splitting and checks, keeps one method for one goal, and refuses the options 3.4 has
+      the options 3.4 has `deliver_sm` leave empty (`scheduleDeliveryTime`, `validityPeriod`).
-      `deliver_sm` leave empty (`scheduleDeliveryTime`, `validityPeriod`).
 
-- [ ] **Let a response this library builds carry error TLVs.** `buildBody()` in `pdu.ts` writes no
+- [ ] **Error TLVs on a response this library builds.** `buildBody()` in `pdu.ts` writes no body for
-      body for any non-zero status, so a server cannot answer a `data_sm` with
+      any non-zero status, so a server cannot answer a `data_sm` with `delivery_failure_reason`,
-      `delivery_failure_reason`, `network_error_code` or `additional_status_info_text`, and a 5.0
+      `network_error_code` or `additional_status_info_text`, and a 5.0 peer gets none of its error TLVs.
-      peer gets none of its error TLVs. 3.4 omits the body on error for `submit_sm_resp` by name;
+      3.4 omits the body on error for `submit_sm_resp` by name; read each response's section before
-      read each response's section before widening it. Reading needs nothing: an error response
+      widening it. Reading needs nothing: an error response carrying a body already parses.
-      carrying a body already parses.
 
-- [ ] **Accept the PROXY protocol on `server()`.** Behind HAProxy or an AWS NLB every session's
+- [ ] **PROXY protocol on `server()`.** Behind HAProxy or an AWS NLB every session's remote address is
-      remote address is the balancer's, so `authenticate` cannot allow-list by IP and logs name the
+      the balancer's, so `authenticate` cannot allow-list by IP and logs name the wrong peer. v1 is
-      wrong peer. v1 is text; v2 is binary and the only one an NLB sends. `smpp` accepts v1 from
+      text; v2 is binary and the only one an NLB sends. `smpp` accepts v1 from anyone; accept either
-      anyone; accept either only from addresses the option names.
+      only from addresses the option names.
 
-- [ ] **Handle `outbind`.** It is in the command table, handled nowhere: a client cannot take an
+- [ ] **`outbind`.** In the command table, handled nowhere: a client cannot take an SMSC's `outbind`
-      SMSC's `outbind` and bind back, and `server()` cannot send one. Rare; take it on with a peer
+      and bind back, and `server()` cannot send one. Rare; take it on with a peer that uses it.
-      that uses it.
 
 - [ ] **Register vendor-specific commands.** 3.4 reserves `command_id` `0x00010200`–`0x000102FF` for
       SMSC vendors; today one arrives as a `PduRefusedError`. `smpp` has `addCommand()`. The same
@@ -623,9 +610,9 @@ Each lands under goal 7: an option or a hook, with the call that passes none unc
       on one coding are an `err`. Settle whether a claim on 0x00 reaches the class groups
       `messageClassEncoding()` reads GSM 7-bit from, which `flash` writes under.
 
-- [ ] **Carry the alphabets SMPP 3.4 names that no encoding carries.** `consts.ENCODING` lists the
+- [ ] **The alphabets SMPP 3.4 names that no encoding carries.** `consts.ENCODING` lists the
-      `data_coding` ids (5.2.19); only `ASCII`, `LATIN1` and `UCS2` can be sent. Those with a
+      `data_coding` ids (5.2.19); only `ASCII`, `LATIN1` and `UCS2` can be sent. Those with a published
-      published definition, and what each costs:
+      definition, and what each costs:
       - 0x01 IA5 (ITU-T T.50, ASCII in practice): trivial.
       - 0x06 ISO-8859-5 (Cyrillic) and 0x07 ISO-8859-8 (Hebrew): 96-entry tables.
       - 0x05 JIS X 0208, 0x0D JIS X 0212, 0x0A ISO-2022-JP and 0x0E KS C 5601: two-octet sets.
@@ -635,34 +622,30 @@ Each lands under goal 7: an option or a hook, with the call that passes none unc
         A Node without full ICU throws from `new TextDecoder()`, which hard rule 1 wraps into an `err`.
       - 0x09 pictogram has no published definition; leave it out.
 
-- [ ] **Read and send the GSM 7-bit national language shift tables.** 3GPP TS 23.038 defines them
+- [ ] **GSM 7-bit national language shift tables.** 3GPP TS 23.038 defines them for Turkish, Spanish
-      for Turkish, Spanish (single shift only), Portuguese and ten Indian languages — Bengali,
+      (single shift only), Portuguese and ten Indian languages — Bengali, Gujarati, Hindi, Kannada,
-      Gujarati, Hindi, Kannada, Malayalam, Oriya, Punjabi, Tamil, Telugu and Urdu — selected per
+      Malayalam, Oriya, Punjabi, Tamil, Telugu and Urdu — selected per message by UDH elements 0x25
-      message by UDH elements 0x25 (locking) and 0x24 (single). They keep that text near GSM's
+      (locking) and 0x24 (single). They keep that text near GSM's segment size instead of UCS2's 67
-      segment size instead of UCS2's 67 characters. Reading means honouring those elements in
+      characters. Reading means honouring those elements in `decodeMessage()`; sending means `detect()`
-      `decodeMessage()`; sending means `detect()` picking a table, with each element's 3 octets off
+      picking a table, with each element's 3 octets off the segment budget. `smpp` has Turkish, Spanish
-      the segment budget. `smpp` has Turkish, Spanish and Portuguese, used only when the caller
+      and Portuguese, used only when the caller writes the UDH.
-      writes the UDH.
 
-- [ ] **Offer packed GSM 7-bit, opt-in.** Everything goes out unpacked, SMPP's convention
+- [ ] **Packed GSM 7-bit, opt-in.** Everything goes out unpacked, SMPP's convention (AGENTS.md, "GSM
-      (AGENTS.md, "GSM 7-bit is sent unpacked"); go-smpp carries a packed codec for SMSCs that want
+      7-bit is sent unpacked"); go-smpp carries a packed codec for SMSCs that want septets. Find an SMSC
-      septets. Find an SMSC that needs it before building it.
+      that needs it before building it.
 
-- [ ] **Give each alphabet in `consts.ENCODING` one name.** Five are spelled twice:
+- [ ] **`consts.ENCODING` spells five alphabets twice.** `CYRILLIC`/`ISO_8859_5`,
-      `CYRILLIC`/`ISO_8859_5`, `HEBREW`/`ISO_8859_8`, `JIS`/`X_0208_1990`,
+      `HEBREW`/`ISO_8859_8`, `JIS`/`X_0208_1990`, `EXTENDED_KANJI_JIS`/`X_0212_1990` and
-      `EXTENDED_KANJI_JIS`/`X_0212_1990` and `LATIN1`/`ISO_8859_1`; `FLASH` is a message class, not
+      `LATIN1`/`ISO_8859_1`; `FLASH` is a message class, not an alphabet. One name each before
-      an alphabet. One name each before registration starts taking names. A breaking change to an
+      registration starts taking names. A breaking change to an export.
-      export.
 
 ### Observability
 
-- [ ] **Add metrics: outbound PDU events and counts of requests waiting.** Inbound traffic has
+- [ ] **Metrics.** Inbound traffic has `data`, `incomingPdu` and `incomingPduObj`; outbound has no
-      `data`, `incomingPdu` and `incomingPduObj`; outbound has no event, and nothing counts requests
+      event, and nothing counts requests in flight, queued for a window slot, waiting for a link, or
-      in flight, queued for a window slot, waiting for a link, or unanswered. `smpp` and
+      unanswered. `smpp` and `@semyonf/smpp` emit `metrics`; cloudhopper keeps per-session counters. An
-      `@semyonf/smpp` emit `metrics`; cloudhopper keeps per-session counters. An
+      `outgoingPdu`/`outgoingPduObj` pair mirrors the inbound events; the counters can be one read-only
-      `outgoingPdu`/`outgoingPduObj` pair mirrors the inbound events; the counters can be one
+      snapshot, read from the owner of each count rather than a second tally that can drift.
-      read-only snapshot, read from the owner of each count rather than a second tally that can
-      drift.
 
 ### Packaging, tests and CI
 
@@ -672,21 +655,21 @@ Each lands under goal 7: an option or a hook, with the call that passes none unc
       `src` (41 files, 209 KB) makes go to definition land in the TypeScript, and lets a debugger or
       `--enable-source-maps` show it.
 
-- [ ] **Add a coverage report and a floor to the gate.** `node --test --experimental-test-coverage
+- [ ] **A coverage report and a floor in the gate.** `node --test --experimental-test-coverage
       --test-coverage-include='src/**' test/*.test.ts` on Node 24.18.0, 2026-09-14: 98.77% lines,
       93.85% branches, 98.28% functions. Gate at 98, 93 and 98 with `--test-coverage-lines`,
-      `--test-coverage-branches` and `--test-coverage-functions`, which Node 22 and later take — a
+      `--test-coverage-branches` and `--test-coverage-functions`, which Node 22 and later take — a job
-      job of its own on 24, since the matrix runs compiled JavaScript — and add it to `main`'s
+      of its own on 24, since the matrix runs compiled JavaScript — and add it to `main`'s required
-      required checks. Raise the floor as coverage rises; never lower it.
+      checks. Raise the floor as coverage rises; never lower it.
 
-- [ ] **Add mutation testing.** `@stryker-mutator/tap-runner` runs `node:test` suites and measures
+- [ ] **Mutation testing.** `@stryker-mutator/tap-runner` runs `node:test` suites and measures whether
-      whether a test notices a change, which coverage cannot; `@semyonf/smpp` runs Stryker in CI.
+      a test notices a change, which coverage cannot; `@semyonf/smpp` runs Stryker in CI. The session
-      The session suites are timer-heavy, so start with the codec and the encodings.
+      suites are timer-heavy, so start with the codec and the encodings.
 
-- [ ] **Build a Node-RED node, as a package of its own.** `@leissner/node-red-smpp` is the only SMPP
+- [ ] **A Node-RED node, as a package of its own.** `@leissner/node-red-smpp` is the only SMPP node in
-      node in the Node-RED library, and by a read of its source it never parses a receipt and never
+      the Node-RED library, and by a read of its source it never parses a receipt and never answers the
-      answers the SMSC's `enquire_link`. Its UI is a fair list of what operators set. It builds on
+      SMSC's `enquire_link`. Its UI is a fair list of what operators set. It builds on this package,
-      this package, never inside it.
+      never inside it.
 
 ## Declined
 
@@ -700,9 +683,9 @@ Each lands under goal 7: an option or a hook, with the call that passes none unc
 
 ## An optional store
 
-- [ ] **Add pooling, and state that survives a restart, through an optional store.** Maintainer's
+- [ ] **Pooling, and state that survives a restart, through an optional store.** Maintainer's call,
-      call, 2026-09-14. It replaces two declines — merge state surviving a restart, and a pool of
+      2026-09-14. It replaces two declines — merge state surviving a restart, and a pool of sessions —
-      sessions — and goal 9 was rewritten for it. Big: design before code.
+      and goal 9 was rewritten for it. Big: design before code.
       - **What it holds.** Receipts still awaited and the groups `DlrMerger` collects. Segments of a
         message already answered but not yet whole, which the peer will not send again (goal 2). The
         concatenation reference, so a restart does not reuse one. For a pool, the ids every session