Drop HTML from your shell.

01Install

One npm install, one human auth step. After that, the agent owns it.

# requires node 20+
$ npm i -g @htmlbin/cli
$ htmlbin login
$ htmlbin publish ./out.html
→ https://htmlbin.dev/p/aB3xK7g

htmlbin login mints an API token via the GitHub device-code flow, ~30 seconds. The token lives at ./.htmlbin/token or ~/.config/htmlbin/token, in that order.

02Built for agents

htmlbin is an API for agents to share HTML; the CLI is the thin layer that lets them call it. Set CLAUDE_CODE, CURSOR_AGENT, CODEX, AIDER, CLINE, AMP_CODE, or DEVIN in the environment and the CLI auto-switches to single-line JSON. No flag needed.

$ CLAUDE_CODE=1 htmlbin publish ./out.html
{"url":"https://htmlbin.dev/p/aB3xK7g","slug":"aB3xK7g","version":1}

The full agent skill is served at htmlbin.dev/.well-known/agent-skills/htmlbin/SKILL.md — agents can fetch it before publishing to learn the rules.

03The PR-preview trick

Idempotent publishes, keyed by metadata. The pattern that makes pull-request previews click.

$ htmlbin publish ./out.html \
    --upsert \
    --metadata repo=u/r \
    --metadata pr=42

First push creates the drop. Every push after updates it. The URL stays stable for the entire life of the PR. Tag with anything you want; --upsert finds the match and re-publishes in place.

04Three backends, one verb

The same publish command, three places it can land. Select with --to <name>, $HTMLBIN_BACKEND, or backend = "..." in ./.htmlbin/config.

cloud

Public previews on htmlbin.dev. The default. Authenticates with an hb_* token.

gh-pages

Org-internal previews behind GitHub SSO. Commits to a gh-pages branch via the Git Data API.

cloudflare

SSO-gated previews via Cloudflare Access. The free tier covers up to 50 users.

05Commands

publish <file>

publish a file, print the URL

update <slug>

mutate an existing drop (PUT new HTML or PATCH metadata)

list

list your drops; filter with --metadata k=v

url <slug>

print the URL for a slug

delete <slug>

remove a drop

login

cloud sign-in via GitHub device code

setup

one-time backend preparation

patterns

install reusable drop templates