
Cws
io.github.mikusnuzPublished by GitHub account mikusnuzv2.0.2Updated Nov 3, 2026
MCP server for Chrome Web Store — extension upload, publish, status, and rollout
Overview
Manages Chrome Web Store extensions from an MCP client: upload ZIP drafts, publish, check review status, cancel submissions, and set rollout percentages.
- What you can do
- Upload a built ZIP as a draft update to an existing Chrome Web Store item
- Publish or submit for review, with publish type, rollout percentage, skip-review and block-on-warnings options
- Check review state, version and deploy percentage, and cancel a pending submission
- Set staged rollout percentages for eligible extensions
- Read and save draft listing fields (description, category, homepage and support URLs) through the developer dashboard
- When to use it
- Useful when you ship a Chrome extension and want an assistant to handle the release loop: pushing a new ZIP, submitting for review, watching status, ramping a staged rollout, or editing draft listing text without opening the dashboard by hand.
- Requirements
- Runs locally as an npm package (cws-mcp) via npx or node, requiring Node.js 20 or newer and Google Chrome installed. Needs Google OAuth2 credentials for the Chrome Web Store API: CWS_CLIENT_ID, CWS_CLIENT_SECRET and CWS_REFRESH_TOKEN, obtained through a desktop OAuth flow with the chromewebstore scope. Optional CWS_PUBLISHER_ID, CWS_ITEM_ID and CWS_DASHBOARD_PROFILE_DIR. Dashboard tools need a signed-in Chrome profile.
Installation
In SourceWeft
- Open Cws in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.
Other MCP clients
Follow the launch instructions in the repository.
README
cws-mcp
MCP server for Chrome Web Store extension management. Upload, publish, and manage Chrome extensions directly from Claude Code or any MCP client.
When to Use
Use this MCP when you need to:
- "Upload a new version of my Chrome extension" — build your ZIP and use the
uploadtool to push it as a draft - "Publish my extension to the Chrome Web Store" — use
publishto submit for review and go live - "Check the review status of my extension" — use
statusto see review state, version, and deploy percentage - "Update my extension's description or category" — use
update-metadatato save and verify the draft listing - "Cancel a pending submission" — use
cancelto withdraw a submission under review - "Set up staged rollout for my extension" — use
publishwith staged rollout, thendeploy-percentageto ramp up
Tools
API Coverage
An upload returning IN_PROGRESS is pending: poll status until lastAsyncUploadState is SUCCEEDED before publishing. FAILED is a tool error. A blocked publish retains error.details, including the warnings that need attention.
This MCP server covers all Chrome Web Store API v2 endpoints:
All API requests use v2. The public API has no listing-text read/write endpoints; dashboard tools use Playwright and a separate signed-in Chrome profile. Saving listing fields never submits for review. Missing fields, unmatched categories, and unconfirmed saves return errors instead of success.
Setup
Requires Node.js 20 or newer, matching the Playwright runtime requirement.
1. Create OAuth2 Credentials
- Go to Google Cloud Console
- Create a project (or select existing)
- Enable Chrome Web Store API
- Create OAuth2 credentials (Desktop app type)
- Note your Client ID and Client Secret
2. Get Refresh Token
Follow Google's OAuth flow for desktop apps using a local loopback redirect URI, PKCE, and the scope https://www.googleapis.com/auth/chromewebstore. Request offline access (access_type=offline; use prompt=consent when you need a new refresh token). Exchange the authorization code using the same redirect URI and keep the refresh token in your MCP client's secret/environment settings. The former copy-and-paste OOB redirect is no longer supported by Google.
3. Configure MCP
Add to your Claude Code MCP settings (~/.claude/settings.local.json):
Or install globally via npm:
Environment Variables
Usage Examples
Check extension status
Upload and publish
Hold publication until after approval
Publish with skip-review
STAGED_PUBLISH holds an approved submission for a later publication; it is not the rollout percentage. Use deployPercentage separately for an eligible extension's gradual rollout.
Stop publishing on validation warnings
The default is false, matching the API. Inspect returned warningInfo.warnings even when publishing succeeds.
Read or save listing fields without submitting for review
Notes:
categorymust match the visible option label exactly in the current dashboard language; English and Korean field labels are supported.- These tools read/save the current dashboard draft, not the published listing or an arbitrary locale. Select the intended localization in the dashboard first; ambiguous fields fail safely.
- Change title, summary, and default locale in
manifest.json/ localized messages, rebuild, anduploadthe ZIP. Use the dashboard directly for icons and screenshots. - First run with
headless=falseif login is required. - Browser profile path defaults to
~/.cws-mcp-profile(override withCWS_DASHBOARD_PROFILE_DIR). - Google Chrome must be installed. Dashboard UI changes can require selector updates; unverified saves return errors. Verify the dashboard before retrying an ambiguous failure.
Staged rollout
Note: deploy-percentage is only available for extensions with 10,000+ seven-day active users. The new percentage must always be higher than the current target.
Migrating from 1.x to 2.0
Google shuts down API v1 on October 15, 2026. Version 2.0 no longer calls it:
getnow returns v2 status. Its oldprojectionargument is rejected; useget-metadata-uifor draft listing text. Published listing text is not exposed by v2.update-metadatanow uses the same dashboard workflow asupdate-metadata-uiand therefore needs Chrome login, not just an API token.- Raw
metadata,title,summary, anddefaultLocaleinputs are rejected with guidance; unsupported inputs are never silently ignored. storeIconPathis no longer accepted as a working upload. The previous generic file-input approach could not verify which asset it changed; upload the icon in the Developer Dashboard instead.
License
MIT
Source: README.md at commit a10f5f7
Tools
0Version history
3- v2.0.2LatestOct 19, 2026
- v2.0.0Oct 8, 2026
- v1.4.1Sep 16, 2026
Score
50% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
- Reached in the last 30 days25 pts
Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.
- Auth declared10 pts
Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.
- Tools listed15 pts
Answer tools/list without a credential, or ship a package that starts in a sandbox without one.
- DescriptionRequired15 pts
- Logo10 pts
- Documentation15 pts
- License10 pts