diff --git a/README.md b/README.md
index b1ee97c..09087f4 100644
--- a/README.md
+++ b/README.md
@@ -61,6 +61,40 @@ npx @gamemaker/gm-cli@latest login <my key>
 gm-cli manual open "sprites" --language=es
 ```
 
+### Publish to GX.Games
+Use `gm-cli gxgames` to publish a game to [gx.games](https://gx.games). Run `gm-cli gxgames --help` for the full list of subcommands.
+
+The flow:
+
+1. **Package** the game as an OperaGX zip:
+   ```sh
+   npx @gamemaker/gm-cli@latest package --target=operagx --output=game.zip
+   ```
+2. **Link** the project to a studio and game (opens the browser to sign in on first use):
+   ```sh
+   npx @gamemaker/gm-cli@latest gxgames link --studioid=<id> --gameid=<id>
+   ```
+   Omit the flags to pick interactively.
+3. **Upload** the zip (prompts for a `X.Y.Z.B` version if `--version` is omitted):
+   ```sh
+   npx @gamemaker/gm-cli@latest gxgames upload --file=game.zip --version=1.0.0.0
+   ```
+4. **Set metadata** required for publishing — title (must be unique across GX.Games), description, age rating, platforms, 16:9 cover, and 16:9 screenshot. Cover and graphic must have an **exact** 16:9 aspect ratio (e.g. 1920×1080):
+   ```sh
+   npx @gamemaker/gm-cli@latest gxgames meta \
+     --title="My Game" \
+     --description="A short description" \
+     --age-rating=EVERYONE \
+     --platforms=DESKTOP,MOBILE \
+     --cover=cover_1920x1080.png \
+     --graphic=screenshot_1920x1080.png
+   ```
+   Each flag overrides one field; omitted flags keep the current server value.
+5. **Publish** to make the game public (opens the published page on success):
+   ```sh
+   npx @gamemaker/gm-cli@latest gxgames publish
+   ```
+
 ## Near future
 > Note: The GameMaker CLI is made for the community and we welcome your feedback! Please suggest features or tell us about any issues you are having.
 
@@ -81,10 +115,6 @@ The `ask` subcommand displays an article directly in your terminal,
 gm-cli manual ask "data structures"
 ```
 
-### Publishing games to the web
-
-Direct integration with [gx.games](https://gx.games) to share your games! 
-
 ### A library to make your own tools
 `gm-cli` will expose its internals as a TypeScript library that you can use to more easily make your own editor tools. 
 
diff --git a/src/commands/gxgames/command.ts b/src/commands/gxgames/command.ts
index 1879a5f..1099f1a 100644
--- a/src/commands/gxgames/command.ts
+++ b/src/commands/gxgames/command.ts
@@ -70,6 +70,7 @@ const gxgamesUploadCommand = buildCommand({
     brief: "Upload a game bundle to GX.Games",
     fullDescription:
       "Uploads a zip bundle to GX.Games. " +
+      "Produce the zip with `gm-cli package --target operagx`. " +
       "Prompts for the version number if --version is not provided.",
   },
 });
@@ -85,7 +86,7 @@ const gxgamesMetaCommand = buildCommand({
         brief: "Game title",
         optional: true,
       },
-      agerating: {
+      ageRating: {
         kind: "parsed",
         parse: String,
         brief:
@@ -124,8 +125,7 @@ const gxgamesMetaCommand = buildCommand({
     brief: "Set or update game metadata required for publishing",
     fullDescription:
       "Set or update metadata for your GX.Games game. " +
-      "Run without flags for an interactive prompt, or pass flags to set specific fields. " +
-      "All flags are optional — omit any flag to be prompted for it interactively.",
+      "Each flag overrides the corresponding field; omitted flags keep their current server value.",
   },
 });
 
diff --git a/src/commands/gxgames/commands/meta-impl.ts b/src/commands/gxgames/commands/meta-impl.ts
index f769eae..7f58dd5 100644
--- a/src/commands/gxgames/commands/meta-impl.ts
+++ b/src/commands/gxgames/commands/meta-impl.ts
@@ -29,7 +29,7 @@ import type {
 
 interface MetaFlags {
   title?: string;
-  agerating?: string;
+  ageRating?: string;
   description?: string;
   platforms?: string;
   cover?: string;
@@ -59,7 +59,7 @@ export default async function (
     title: flags.title ?? game.title,
     shortDescription: flags.description ?? game.shortDescription,
     ageRating:
-      (flags.agerating?.toUpperCase() as
+      (flags.ageRating?.toUpperCase() as
         | GameDevUpdateGameRequestAgeRatingEnum
         | undefined) ??
       (game.ageRating as GameDevUpdateGameRequestAgeRatingEnum),
diff --git a/src/commands/gxgames/commands/upload-impl.ts b/src/commands/gxgames/commands/upload-impl.ts
index f076959..685b30a 100644
--- a/src/commands/gxgames/commands/upload-impl.ts
+++ b/src/commands/gxgames/commands/upload-impl.ts
@@ -24,6 +24,12 @@ import type { ProjectPath } from "~/project";
 
 import { LinkStorage } from "../api";
 
+const VERSION_RE = /^\d+\.\d+\.\d+\.\d+$/;
+const validateVersion = (v: string | undefined): string | undefined =>
+  v && VERSION_RE.test(v)
+    ? undefined
+    : "Version must be X.Y.Z.B (e.g. 1.0.0.0)";
+
 export default async function (
   this: Context,
   flags: { file: string; version?: string },
@@ -49,12 +55,17 @@ export default async function (
 
   let version: string;
   if (flags.version != null) {
+    const err = validateVersion(flags.version);
+    if (err) {
+      throw new KnownError(err);
+    }
     version = flags.version;
   } else {
     const v = await p.text({
       message: "Version",
       placeholder: "0.0.1.0",
       defaultValue: previousVersion,
+      validate: validateVersion,
     });
     if (p.isCancel(v)) {
       return process.exit(0);