CLI reference

The package installs a single binary: headless-prerender.

headless-prerender <command> [options]

Command	Purpose
serve	Start the prerender HTTP server
render <url>	Render one URL and print or save the HTML
help	Print usage (also --help)

serve

Starts a long-running HTTP server.

headless-prerender serve --port 3000 --cache-ttl 60000

Endpoints

Route	Description
GET /render?url=<page>	Returns the fully-rendered HTML of <page>
GET /health	Returns {"ok":true}

Options

Flag	Default	Description
--port <n>	3000	TCP port to listen on
--host <host>	0.0.0.0	Interface to bind
--cache-ttl <ms>	0	In-memory cache TTL; 0 disables caching
--token <string>	none	Require this token via ?token= or x-prerender-token

Plus all common render options.

render <url>

Renders one page and exits.

headless-prerender render https://example.com --extra-wait 500 --out page.html

Flag	Default	Description
--out <file>	stdout	Write the HTML to a file instead of standard output

Plus all common render options.

Progress and result details are written to stderr, so --out is optional and piping the HTML on stdout stays clean:

headless-prerender render https://example.com > page.html

Common render options

These apply to both serve and render.

Flag	Default	Description
--timeout <ms>	20000	Navigation timeout
--wait-until <event>	networkidle2	load, domcontentloaded, networkidle0, or networkidle2
--extra-wait <ms>	0	Extra settle time after the page is considered loaded
--user-agent <string>	Mozilla/5.0 (compatible; headless-prerender)	User-Agent sent to the target page
--allow-origin <origin>	none	Only render URLs on this origin; repeatable
--executable-path <path>	bundled Chromium	Path to a Chromium binary

Restricting origins

Pass --allow-origin more than once to allow several origins:

headless-prerender serve \
  --allow-origin https://www.example.com \
  --allow-origin https://blog.example.com

Any request for a URL outside the list returns an error.

Exit codes

Code	Meaning
0	Success
1	Invalid arguments, or a render/serve error