dev-browser

Original：🇺🇸 English

Not Translated

Browser automation with persistent page state. Use when users ask to navigate websites, fill forms, take screenshots, extract web data, test web apps, or automate browser workflows. Trigger phrases include "go to [url]", "click on", "fill out the form", "take a screenshot", "scrape", "automate", "test the website", "log into", or any browser interaction request.

3installs

Sourcejtsang4/dev-browser

Added on2026-02-10

NPX Install

npx skill4agent add jtsang4/dev-browser dev-browser

SKILL.md Content

Dev Browser Skill

Use

dev-browser

CLI to run multi-step browser automation with persistent page state.

Defaults

Prefer multi-step execution: Use one
```
run --code
```
block for multiple actions whenever possible.
Reuse page names: Keep the same
```
--page
```
name across turns to preserve state.
Control via daemon commands: Explicitly use
```
ensure/status/stop/clean
```
.
CLI must be available: Ensure
```
dev-browser
```
command is installed and on
```
PATH
```
(from the separated CLI package).

Setup

If

dev-browser

command is missing, install CLI globally:

bash

pnpm add -g @jtsang/dev-browser-cli
# or: npm install -g @jtsang/dev-browser-cli

Ensure daemon is running before actions:

bash

dev-browser daemon ensure --mode launch --json
# optional: choose launch engine (default: patchright)
dev-browser daemon ensure --mode launch --engine playwright --json

Use extension mode when user wants their existing Chrome session:

bash

dev-browser daemon ensure --mode extension --json

Useful lifecycle commands:

bash

dev-browser daemon status --json
dev-browser daemon stop --mode launch
dev-browser daemon clean --stale-only
dev-browser doctor

Run Multi-Step Scripts

Use

run --code

as the primary execution command.

bash

dev-browser run --mode launch --page checkout --json --code '
await page.goto("https://example.com");
await helpers.waitForPageLoad(page);
await page.fill("input[name=email]", "test@example.com");
await page.click("button[type=submit]");
return { url: page.url(), title: await page.title() };
'

Execution Context

--code

runs as async JavaScript function body with injected values:

```
page
```
- persistent Playwright
```
Page
```
for
```
--page
```
name
```
client
```
- dev-browser client instance
```
helpers
```
- utility helpers (
```
waitForPageLoad
```
)
```
log(entry)
```
- structured step logs collected in output

Output Contract

Success (

ok: true

) includes:

```
mode
```
```
pageName
```
```
data
```
(your returned value)
```
logs
```
```
timingMs
```

Failure (

ok: false

) includes:

```
error.code
```
(
```
RUN_TIMEOUT
```
or
```
RUN_EXEC_ERROR
```
)
```
error.message
```
```
error.retryable
```

Workflow Pattern

For complex tasks:

```
daemon ensure
```
Run one multi-step
```
run --code
```
Evaluate JSON result
If needed, run another
```
run --code
```
with same
```
--page
```
On completion,
```
daemon stop
```
(or rely on idle TTL)

Page State Inspection

Use

run --code

for debugging snapshots/screenshots:

bash

dev-browser run --page debug --json --code '
await page.screenshot({ path: "debug.png", fullPage: true });
const snapshot = await client.getAISnapshot("debug");
return { url: page.url(), title: await page.title(), snapshot };
'

Notes

```
run --code
```
accepts JavaScript only (no TypeScript syntax inside code body).
Same
```
--page
```
name is serialized by lock to prevent concurrent mutation conflicts.
Runtime data is stored under
```
~/.dev-browser/
```
(override with
```
DEV_BROWSER_HOME
```
).