diff --git a/.github/workflows/publish-vscode.yml b/.github/workflows/publish-vscode.yml
index c860ae3..eecd611 100644
--- a/.github/workflows/publish-vscode.yml
+++ b/.github/workflows/publish-vscode.yml
@@ -41,7 +41,7 @@ jobs:
           PUBLISHER="$(node -p "require('./package.json').publisher")"
           EXTENSION="$(node -p "require('./package.json').name")"
           test "$RELEASE_TAG" = "v$VERSION"
-          test "$PUBLISHER" = "om-core"
+          test "$PUBLISHER" = "cloudcell"
           test "$EXTENSION" = "om-tools"
           test "$(git rev-parse HEAD)" = "$(git rev-list -n 1 "$RELEASE_TAG")"
           git fetch --no-tags origin main
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d23bd34..ae7fbb7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## 0.1.2
+
+- Correct the extension publisher identifier to `cloudcell` for Visual Studio Marketplace publishing.
+- No changes to the OM Core extension functionality since 0.1.0.
+
 ## 0.1.0 (preview)
 
 First public preview.
diff --git a/MARKETPLACE-PUBLISHING.md b/MARKETPLACE-PUBLISHING.md
index 82e0464..a40696d 100644
--- a/MARKETPLACE-PUBLISHING.md
+++ b/MARKETPLACE-PUBLISHING.md
@@ -1,10 +1,10 @@
 # VS Code Marketplace publishing
 
-The extension is published as `om-core.om-tools` from GitHub releases using **Visual Studio Marketplace Trusted Publishing (GitHub Actions OIDC)**. No Marketplace PAT or Azure account secret is required.
+The extension is published as `cloudcell.om-tools` from GitHub releases using **Visual Studio Marketplace Trusted Publishing (GitHub Actions OIDC)**. No Marketplace PAT or Azure account secret is required.
 
 ## One-time setup (repository owner)
 
-1. Open [Marketplace publisher management](https://marketplace.visualstudio.com/manage/publishers/), sign in, and create or select the **`om-core`** publisher. This identifier must match `package.json`.
+1. Open [Marketplace publisher management](https://marketplace.visualstudio.com/manage/publishers/), sign in, and create or select the **`cloudcell`** publisher. This identifier must match `package.json`.
 2. In that publisher, open **Trusted Publishing** > **Create**.
 3. Set the policy fields **exactly**:
    - Policy name: `OM Tools releases` (any descriptive name)
@@ -17,6 +17,12 @@ The extension is published as `om-core.om-tools` from GitHub releases using **Vi
 
 **Do not** put PATs in source, Actions secrets, or workflow inputs. The Marketplace's OIDC trust policy permits the named GitHub workflow to obtain an expiring, single-use publishing credential.
 
+## First publication after correcting the publisher
+
+The GitHub release `v0.1.0` was created while the extension manifest still contained publisher `om-core`, so its Marketplace publishing attempt failed with `The requested publisher doesn't exist`. Do not move or replace that historical tag. The corrected publisher identifier is `cloudcell` and the first Marketplace release should use `v0.1.2`.
+
+Before publishing, confirm that the **cloudcell** Marketplace publisher has a Trusted Publishing policy matching GitHub repository `cloudcell/om-tools`, workflow `publish-vscode.yml`, and an empty environment field. The GitHub release's tag must match the version in both `package.json` and `package-lock.json`.
+
 ## Publishing a version
 
 1. Merge reviewed changes into `main` and confirm the quality/security workflow passes.
@@ -27,13 +33,13 @@ The extension is published as `om-core.om-tools` from GitHub releases using **Vi
    git checkout main
    git pull --ff-only
    # package.json must now contain 0.1.0, for example
-   git tag -a v0.1.0 -m "OM Tools 0.1.0"
-   git push origin v0.1.0
+   git tag -a v0.1.2 -m "OM Tools 0.1.2"
+   git push origin v0.1.2
    ```
 
 4. On GitHub, open **Releases > Draft a new release**, select that tag, and publish a **normal** release (not draft/prerelease).
-5. GitHub Actions runs [Publish VS Code Marketplace](../workflows/publish-vscode.yml). It checks tag/version equality, ensures the tagged commit is already reachable from `main`, installs locked dependencies, typechecks, builds, scans, packages, examines the VSIX, then publishes using `vsce publish --oidc`.
-6. After a successful run, check the extension page: https://marketplace.visualstudio.com/items?itemName=om-core.om-tools
+5. GitHub Actions runs [Publish VS Code Marketplace](.github/workflows/publish-vscode.yml). It checks tag/version equality, ensures the tagged commit is already reachable from `main`, installs locked dependencies, typechecks, builds, scans, packages, examines the VSIX, then publishes using `vsce publish --oidc`.
+6. After a successful run, check the extension page: https://marketplace.visualstudio.com/items?itemName=cloudcell.om-tools
 
 Only published **non-prerelease** GitHub releases trigger publication. Pushes to `main` or `dev` do **not** publish. If the release cannot obtain an OIDC credential, double-check the Marketplace policy owner, repository, filename, and blank environment field. If a version is already published, increment the package version, create a new tag, and publish a new GitHub release; do not reuse a published version.
 
@@ -47,4 +53,4 @@ Only published **non-prerelease** GitHub releases trigger publication. Pushes to
 - Marketplace release is distinct from publishing to Open VSX (VSCodium). Open VSX requires its own publisher registration and workflow.
 - The **first** successful publish cannot happen until the publisher account and Trusted Publishing policy have been created manually.
 
-Reference: https://code.visualstudio.com/api/working-with-extensions/publishing-extension#publish-with-github-actions-and-trusted-publishing
+Reference: https://code.visualstudio.com/api/working-with-extensions/publishing-extension
diff --git a/package-lock.json b/package-lock.json
index f6b7726..da1cac8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "om-tools",
-  "version": "0.1.0",
+  "version": "0.1.2",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "om-tools",
-      "version": "0.1.0",
+      "version": "0.1.2",
       "license": "AGPL-3.0-or-later",
       "devDependencies": {
         "@types/node": "^20.11.0",
diff --git a/package.json b/package.json
index 2b92872..6a736c5 100644
--- a/package.json
+++ b/package.json
@@ -2,8 +2,8 @@
   "name": "om-tools",
   "displayName": "OM Core",
   "description": "Multidimensional modeling engine GUI for OM Core — connects to the om-core runtime.",
-  "version": "0.1.0",
-  "publisher": "om-core",
+  "version": "0.1.2",
+  "publisher": "cloudcell",
   "license": "AGPL-3.0-or-later",
   "repository": {
     "type": "git",