CHANGELOG.md

@@ -8,9 +8,12 @@
   recovery contracts, including stable actor-scoped request keys.
 - Add `printer-media-v1` capability negotiation; selected-profile jobs require
   a supporting current client, including after capability downgrade/reconnect.
-- Retain wire version 1 and the realtime transport. Printing extension 2.2.0
-  advertises the additive native routes. Consumer runtime, installed and physical
+- Retain wire version 1 and the realtime transport. Printing extension 2.3.0
+  advertises the additive native routes; 2.2.0 is the separate rendering extension
+  and carries no media negotiation. Consumer runtime, installed and physical
   acceptance remain required before a coordinated release.
+- Add the [extension version registry](docs/VERSIONS.md). No schema or fixture shape
+  changed for the 2.2 to 2.3 reservation.
 
 ## 0.3.0-rc.1 — 2026-10-31
 

README.md

@@ -5,7 +5,8 @@ Shared contract for the [QQQ 4.1+ printing QBit](https://github.com/QRun-IO/qbit
 Current release candidate: [**0.3.0-rc.1**](https://github.com/QRun-IO/qqq-print-protocol/releases/tag/v0.3.0-rc.1). Previous distribution: [**0.2.0-rc.1**](https://github.com/QRun-IO/qqq-print-protocol/releases/tag/v0.2.0-rc.1). Wire protocol: **v1**. This repository supplies specification, JSON Schema and synthetic compatibility fixtures; install the Windows connector and integrate the QBit from their own repositories to print documents.
 
 The next candidate, **0.4.0-rc.1**, adds the [printer media and operator
-contract](docs/PRINTER-MEDIA.md) for printing semantic extension **2.2.0**. It is
+contract](docs/PRINTER-MEDIA.md) for printing semantic extension **2.3.0** (see the
+[extension version registry](docs/VERSIONS.md); 2.2 is rendering only). It is
 under consumer qualification and is not a published release. Media profiles
 represent configured Windows queue defaults with exact revision binding;
 operator access uses normal current-user and tenant authorization without

docs/PRINTER-MEDIA.md

@@ -2,9 +2,12 @@
 
 This additive contract is under implementation for the Echo integration. It is
 not advertised by the installed 0.3.2 client. Existing wire version 1 and the
-WebSocket subprotocol remain unchanged. The server extension is 2.2.0 in the
-implementation branch; immutable consumer artifacts must be qualified together
-before publication. Older 2.x deployments do not promise the operator routes.
+WebSocket subprotocol remain unchanged. The feature minimum is printing extension
+2.3.0 (see [VERSIONS.md](VERSIONS.md)); immutable consumer artifacts must be
+qualified together before publication. A client must offer `printer-media-v1` only
+after discovering a stable 2.3+ extension within major two, so a 2.2 (rendering)
+server keeps it a three-capability peer. Older 2.x deployments do not promise the
+operator routes.
 
 A client advertising `printer-media-v1` reports optional `mediaProfiles` in each
 exposed printer's inventory. The initial implementation reports at most one

docs/SESSION-STATE.md

@@ -10,7 +10,7 @@ dimension options. These tests establish the draft wire shape only.
 
 Matching Windows discovery/revalidation, least-privilege operator catalog and
 submission, and atomic retained-source adoption are active in separate consumer
-branches. The server source targets extension 2.2.0; no compatible published
+branches. The server source targets extension 2.3.0 (2.2.0 is rendering on protected main); no compatible published
 consumer tuple is qualified yet. The installed 0.3.2 client does not advertise
 this capability. No physical output was submitted.
 

docs/VERSIONS.md

@@ -0,0 +1,41 @@
+# Extension version registry
+
+Three version numbers are independent. Do not compare them.
+
+| Number | Meaning | Current |
+| --- | --- | --- |
+| Wire payload version | Shape of the JSON messages in this repository | 1 |
+| WebSocket subprotocol | Framing and message envelope | `qqq-printing.v1` |
+| Printing semantic extension | Server feature level discovered at `/qqq/v1/version` | see below |
+
+## Printing semantic extension
+
+Extension versions are discovered, never assumed. Within major 2 each minor is
+additive and keeps the earlier behavior.
+
+| Extension | Adds | Contract |
+| --- | --- | --- |
+| 2.0.0 | Authenticated realtime channel is required for native claims; no polling fallback | [REALTIME.md](REALTIME.md) |
+| 2.1.0 | Record, table-list and text print processes | server documentation |
+| 2.2.0 | Render-to-PDF process, header and footer values, content sections. No media negotiation | server documentation |
+| 2.3.0 (unreleased, reserved) | Least-privilege operator catalog, submission and request lookup; reported queue-default media and `printer-media-v1`; opt-in retained-source facade | [PRINTER-MEDIA.md](PRINTER-MEDIA.md) |
+
+## Negotiation rules
+
+- A client advertises a capability only when it supports it **and** the discovered
+  extension is a stable `major.minor.patch` version in major 2 at or above the
+  feature minimum. `printer-media-v1` has minimum 2.3.0.
+- A client facing 2.0, 2.1 or 2.2 stays a three-capability peer (`realtime-v1`,
+  `REFRESH_INVENTORY`, `CANCEL_SPOOL`) and sends no media inventory.
+- A server must not let a client that did not advertise `printer-media-v1` claim a
+  job that carries a media selection, whatever extension version that client
+  discovered.
+- Capabilities are re-evaluated on each new socket, so a server upgrade from 2.0
+  to 2.3, or a downgrade from 2.3 to 2.2, takes effect at the next reconnect
+  without a polling schedule.
+- Pre-release, ambiguous or malformed versions (`2.3.0-rc.1`, `2.3`, `02.3.0`,
+  four-part values) never enable a feature.
+
+The 2.3.0 number is reserved for the unreleased operator, media and retained-source
+feature set. It is not a published release until consumer artifacts are qualified
+together.