dsh-playwright-cli

Drive a real browser from DeepSeek Harness: one tool, playwright_cli, wraps microsoft/playwright-cli, plus a bundled playwright-cli skill that teaches the model the command vocabulary.

playwright-cli itself recommends CLI + skills over MCP for coding agents: commands are short, and the page snapshot goes to a file instead of a giant tool schema or accessibility tree. This plugin keeps that design and only adds the two missing pieces — a tool the model can call, and a skill that is discovered and loaded on demand.

中文说明见 README.zh.md。

Install

In the app: Plugins → Plugin Manager → install bundle → dsh-playwright-cli.

From a shell, when the Harness CLI is on your PATH:

dsh plugin --profile <your-profile> add dsh-playwright-cli

From an agent: plugin_manager with action: install_bundle, target: dsh-playwright-cli.

PATH collisions are common on Windows (dsh may belong to another product). If dsh plugin is not the Harness CLI, use the in-app Plugin Manager.

playwright-cli must be available on the machine:

npm install -g @playwright/cli@latest

And a browser has to exist — playwright-cli ships none. Either download its Chromium once:

playwright-cli install-browser chrome-for-testing

or reuse a browser that is already installed, which needs no download at all:

playwright_cli  open https://example.com --browser=msedge

Quick start

playwright_cli  open https://playwright.dev --browser=msedge
playwright_cli  snapshot --depth=4
   → [artifacts] C:\...\.playwright-cli\page-....yml   (read this file to get refs)
playwright_cli  click e15
playwright_cli  fill e7 "user@example.com"
playwright_cli  screenshot --filename=shot.png
playwright_cli  close

Every result carries the page status, the artifacts it produced (absolute paths), and the CLI's exit code. --raw returns just the value, e.g. --raw eval "document.title".

Tool parameters

Parameter	Required	Meaning
command	yes	One playwright-cli command without the playwright-cli prefix. Quote arguments containing spaces.
session	no	Named browser session (-s=<name>), for isolating parallel tasks.
workdir	no	Working directory; artifacts land in <workdir>/.playwright-cli/. Defaults to the session directory.
timeoutMs	no	Per-call wall clock limit (default from config, capped at 900000).

Configuration

Every field is optional and lives in the profile's cordis.patch.yml under the playwright-cli row:

Field	Default	Meaning
executable	auto-discovered	Absolute path to playwright-cli.js (run with nodePath) or to a real executable
nodePath	node from PATH	Node used for the CLI and the browser daemon it spawns
session	none	Default session name
timeoutMs	120000	Per-command limit
disableUpdateNotifier	true	Sets NO_UPDATE_NOTIFIER=1 (see the Node 24 note below)
env	{}	Extra environment, e.g. PLAYWRIGHT_MCP_BROWSER: chrome

How it works

• No shell. The command line is tokenized and passed as an argv vector to node playwright-cli.js …, so & in URLs, spaces in paths, --data="k=v" and Windows quoting cannot corrupt a command.
• Discovery. It walks up from the session directory looking for a local node_modules/@playwright/cli or node_modules/playwright, then checks the usual global npm, pnpm and Homebrew locations. executable overrides all of it.
• Real Node, not the Host binary. The desktop Host runs as Electron-as-node (ELECTRON_RUN_AS_NODE=1), so process.execPath is the app binary. playwright-cli re-spawns its browser daemon with that path and dies with too many arguments; the plugin therefore resolves a real node from PATH first.
• Exit codes are honest. playwright-cli's update notifier crashes the process after a successful command on Node 24 (exit code becomes 0xC0000409); the notifier is disabled by default.
• Artifacts are files. Snapshots, screenshots, PDFs, videos, traces and console logs are resolved to absolute paths and listed under [artifacts], so the model reads them with read / read_image instead of paying for them in the result.
• Hints, not guesses. The two first-run failures (no browser installed, browser not started) get an extra [hint] line with the exact next command.

Troubleshooting

Symptom	Cause	Fix
playwright-cli is not installed or was not found	no local/global install	npm i -g @playwright/cli@latest, or set executable
Browser "chrome-for-testing" is not installed	no bundled browser	playwright_cli install-browser chrome-for-testing, or --browser=msedge
Chromium distribution 'chrome' is not found	Chrome not in its default path	--browser=msedge or --browser=chrome
too many arguments. Expected 1 argument but got 2	CLI launched with the Electron binary	leave nodePath unset so the plugin resolves node
The browser '<name>' is not open	session idle-closed or never opened	open again (add --persistent to keep the profile)
百度安全验证 page on Baidu	site-level anti-automation captcha	not a plugin bug: report the wall, try another engine
snapshot only has header/footer	results rendered after the command returned	re-run snapshot, or use find "<text>"

Maintaining this plugin

Repository layout

Path	Owns	Update it when
index.js	Tool schema, spawn, discovery, artifacts, hints, presenters	CLI flags/output shape change, or DSH's ToolDefinition changes
skill.js	Model-facing skill text (command table, loop, triage)	the command surface changes
cordis.patch.yml	Loader row + default config + field comments	you add a config key
locale/*.json, icon.svg	Plugin Manager title, description, icon	wording/branding
README.md, README.zh.md	user + maintainer docs	any behavior change

Adapting to a new playwright-cli release

1. npm view @playwright/cli version, then npm i -g @playwright/cli@latest.
2. playwright-cli --help — compare the command list with the table in skill.js. The skill is the model's contract, so keep it in sync before anything else.
3. Check open / attach flags (--browser, --device, --persistent, --profile, --config). New flags normally need docs only, no code.
4. Check the output markers: ### Page, ### Snapshot, [Snapshot](.playwright-cli/…), ### Events with console-….log#L1-L6. If a path shape changes, adjust MARKDOWN_LINK, FILE_TOKEN and the #L… stripping in collectArtifacts().
5. Check session selection: the plugin passes -s=<name> and sets PLAYWRIGHT_CLI_SESSION. If a release starts rejecting one of them, drop the env assignment in execute().
6. Check the error strings matched by hintFor(): is not installed, Chromium distribution 'chrome' is not found, is not open, please run open first.
7. Run the smoke test below, then bump the version and the changelog.

The output schema is enforced

DSH validates the tool's returned value against output.schema; a mismatch fails the whole call with returned invalid output. Declare every nullable field as oneOf: [{type:'string'}, {type:'null'}] (this bit us once with signal: null), and build the returned object and the schema together.

Adapting to a new DSH release

1. dsh --version; only raise engines.dsh when you depend on something new.
2. Re-check the four services the plugin uses. In a live session: cordis_inspect_query with platform: host, provider: Service, input: {"service":"tools"} (also subprocess, skills, workingDirectory).
3. Confirm ctx.subprocess.resolveExecutable('node') still resolves; if a Host stops running as Electron-as-node, the fallback to process.execPath keeps working either way.
4. This plugin intentionally ships no Config schema (it would add a schemastery dependency). If in-app config editing starts requiring one, add export const Config.
5. Reinstall and confirm both halves registered: the tool in the agent's tool list and playwright-cli in the skill catalog.

Release checklist

Semver: patch = docs/hints, minor = new commands or config keys (backward compatible), major = renamed package/row, removed config, renamed tool.

npm pack --dry-run          # confirm index.js, skill.js, patch, locale, icon, docs, LICENSE
git add -A && git commit -m "release: vX.Y.Z"
git tag vX.Y.Z && git push --follow-tags
npm publish                 # add --provenance when publishing from CI

Then verify from a clean state:

dsh plugin --profile <profile> remove dsh-playwright-cli
dsh plugin --profile <profile> add dsh-playwright-cli

and run the smoke test. Keep CHANGELOG.md current.

Local development loop

The profile links this directory, but the Host caches the loaded module. After editing index.js, skill.js or cordis.patch.yml, remove and re-install the bundle (Plugin Manager toggle, or remove_bundle + install_bundle through plugin_manager); only a reload picks up new code.

Smoke test

Command	Expected
--version	version line, exit=0
list	(no browsers) or the open sessions
open https://example.com --browser=msedge	page title, .playwright-cli/page-*.yml artifact
find "Example"	matching nodes with context
screenshot --filename=shot.png	shot.png under absolute [artifacts]
close	Browser '<name>' closed

Search-engine smoke tests are the honest end-to-end check: Bing/Google work headless; Baidu returns a captcha page to automation and should be reported, not retried.

Publishing

1. Replace the placeholders in package.json: YOUR NAME, YOUR_GITHUB_USER (three URLs).
2. git init && git branch -M main, create the GitHub repository, push.
3. npm login (2FA accounts need an OTP), then npm publish.
4. Publish must go to the public npm registry; mirrors such as registry.npmmirror.com are for installing, not for npm publish.
5. Optional: publish from GitHub Actions with --provenance (id-token: write), or configure npm trusted publishing for the repository.

Getting listed in the in-app market

Direct install by package name works as soon as the package is on npm. The Plugin Market (dshmarket) reads a curated catalog, https://awesome-dsh-plugin.com/plugins.json, fetched fresh on every request; entries carry name, description, category (at least one), and a source (npm package or URL/repo). Listing is curated — submit an entry to that catalog (its repository accepts PRs/issues for new plugins) with:

{
  "name": "dsh-playwright-cli",
  "description": "microsoft/playwright-cli as a DSH tool plus a bundled skill.",
  "category": ["tool", "browser"],
  "source": { "kind": "npm", "pkg": "dsh-playwright-cli" }
}

Users can also add that catalog URL manually under Plugins → Discover → Index sources.

License and credits

MIT for this plugin. The skill text in skill.js is adapted from microsoft/playwright-cli's SKILL.md (Apache-2.0, Copyright Microsoft Corporation); see LICENSE.