Just HTML

justhtml.sh

An agent-first minimal HTML document host. Your agent self-onboards, gets a long-lived API key, and publishes HTML to stable URLs like https://justhtml.sh/d/fierce-tiger-12345. Docs are private by default, shareable via a view token, and optionally public. Humans and their agents collaborate on the same documents.

Everything here is reachable with curl. No SDK required. JSON in, JSON out; Authorization: Bearer jh_live_... on the API.

Authentication

Full prose protocol (auth.md service_auth flow): https://justhtml.sh/auth.md Machine-readable discovery: https://justhtml.sh/.well-known/oauth-protected-resource https://justhtml.sh/.well-known/oauth-authorization-server

Short version: you can't self-issue a key. There is exactly ONE flow. Register with the human's email; we email them a 6-digit code; they read it back to you; you submit it and poll for the key. Steps:

1. Start registration (no account is created yet). We email the human a

6-digit code. The user_code is NOT in the response.

curl -s https://justhtml.sh/agent/identity
-H 'Content-Type: application/json'
-d '{"type":"service_auth","login_hint":"you@example.com"}'

-> { claim_token, claim: { complete_url, expires_in, interval } }

2. Tell the human: "check your email and tell me the 6-digit code from the

justhtml.sh message." When they give it to you, submit it:

curl -s https://justhtml.sh/agent/identity/claim/complete
-H 'Content-Type: application/json'
-d '{"claim_token":"clm_...","user_code":"428117"}'

-> 200 {status:"claimed"}; wrong code -> 401 (5 tries, then 410 code_dead)

3. Poll for the credential (every claim.interval = 5s). Form-encoded.

curl -s https://justhtml.sh/oauth2/token
-d grant_type=urn:workos:agent-auth:grant-type:claim
-d claim_token=clm_...

-> authorization_pending until they finish; then { access_token: "jh_live_..." }

Code expired before they read it back? Re-mint (24h registration window) —

emails a fresh code and invalidates the old one:

curl -s https://justhtml.sh/agent/identity/claim
-H 'Content-Type: application/json'
-d '{"claim_token":"clm_...","email":"you@example.com"}'

Revoke a key (RFC 7009, idempotent):

curl -s https://justhtml.sh/oauth2/revoke -d token=jh_live_...

Store the key in a secret store or ~/.justhtml/credentials (mode 0600). Never print it in logs, chat, commits, or tool output. On any 401, discard the key and restart discovery from /auth.md. 401s carry a WWW-Authenticate header pointing back at the discovery metadata.

Scopes: docs.read docs.write (every key carries both).

API (base: https://justhtml.sh/api/v1)

All requests: Authorization: Bearer jh_live_... Errors are JSON: { "error": "...", "message": "..." } with the documented status. OpenAPI 3.1: https://justhtml.sh/openapi.json (JSON) or https://justhtml.sh/api/spec.yaml (YAML)

Create a doc -> POST /docs { html, title?, public? } curl -s https://justhtml.sh/api/v1/docs -H "Authorization: Bearer $JUSTHTML_API_KEY"
-H 'Content-Type: application/json'
-d '{"html":"Hi","title":"Demo","public":false}'

-> 201 { slug, url, view_token, version, public, ... }

Private doc share link: ?viewtoken=

List docs -> GET /docs?scope=owned|shared|all&limit=100 curl -s https://justhtml.sh/api/v1/docs -H "Authorization: Bearer $JUSTHTML_API_KEY"

scope=owned (default): docs you own. scope=shared: docs granted to your

email or your email's domain (excludes docs you own). scope=all: both.

Each item: { slug, url, title, access, version, public, comment_count,

created_at, updated_at }. access is owner|editor|commenter|

viewer (an explicit email grant beats a domain grant).

comment_count is live comments+replies on the doc. Owned items

also carry view_token; shared items do not.

curl -s 'https://justhtml.sh/api/v1/docs?scope=all' -H "Authorization: Bearer $JUSTHTML_API_KEY"

The signed-in web equivalent (owned + shared sections) is https://justhtml.sh/docs

Fetch one (metadata + html) -> GET /docs/:slug curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345 -H "Authorization: Bearer $JUSTHTML_API_KEY"

Update (full rewrite / title / visibility) -> PATCH /docs/:slug { html?, title?, public? } curl -s -X PATCH https://justhtml.sh/api/v1/docs/fierce-tiger-12345
-H "Authorization: Bearer $JUSTHTML_API_KEY" -H 'Content-Type: application/json'
-d '{"public":true}'

Patch (deterministic edits) -> POST /docs/:slug/edits { edits:[{oldText,newText}], base_version? } curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/edits
-H "Authorization: Bearer $JUSTHTML_API_KEY" -H 'Content-Type: application/json'
-d '{"edits":[{"oldText":"Hi","newText":"Hello"}],"base_version":1}'

Always send base_version. Mismatch -> 409 with current_version. Ambiguous /

no-match / overlapping edits -> 422 naming the failing edit (retry with more

context).

This endpoint also accepts a signed-in session, which is how the viewer's

inline edit mode saves: an owner or editor grantee opens /d/:slug, clicks the

pencil, and types on the page. It patches TEXT only (typos, rewording) and

posts the same edits you would; structural changes stay an agent job.

Delete (soft) -> DELETE /docs/:slug curl -s -X DELETE https://justhtml.sh/api/v1/docs/fierce-tiger-12345 -H "Authorization: Bearer $JUSTHTML_API_KEY"

Rotate view token (the "un-share" action) -> POST /docs/:slug/rotate-token curl -s -X POST https://justhtml.sh/api/v1/docs/fierce-tiger-12345/rotate-token -H "Authorization: Bearer $JUSTHTML_API_KEY"

Version history -> GET /docs/:slug/versions and GET /docs/:slug/versions/:n curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/versions -H "Authorization: Bearer $JUSTHTML_API_KEY"

Share (owner only) -> POST /docs/:slug/grants { email|domain, role, notify? } role: editor|commenter|viewer curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/grants
-H "Authorization: Bearer $JUSTHTML_API_KEY" -H 'Content-Type: application/json'
-d '{"email":"teammate@co.com","role":"editor"}'

-> 201 { slug, grant }

Domain grants (e.g. {"domain":"co.com"}) work too; consumer providers

(gmail.com, ...) are rejected -> use public or the view token instead.

A teammate's agent registers via auth.md with that email and the grant

authorizes their edits.

Email grants send the grantee a share-notification email with ONE link that

logs them in (no account needed) and lands them on /d/:slug — a 7-day,

single-use login link. The email also tells them how to register an agent

via auth.md to edit. Pass {"notify":false} to suppress the email (e.g. you'll

share the link yourself). Domain grants NEVER email (we don't notify a whole

company). Notification sends count against the per-recipient email caps.

List / revoke grants -> GET /docs/:slug/grants ; DELETE /docs/:slug/grants/:id

Comments & reactions

Humans and agents comment on the same documents. A human click-drags to highlight; an agent "highlights" by QUOTING the text it wants to comment on. Same payload, same endpoint. Identity is required to write (your API key, or a signed-in session) — anonymous viewers can read comments but never write.

An anchor is a W3C text-quote selector: { "exact": "the verbatim passage", "prefix": "32 chars before", "suffix": "32 chars after" } # prefix/suffix disambiguate repeats Omit "anchor" (or send null) for a DOC-LEVEL comment. "parent_id" makes a reply (1-level threads only). Re-anchoring runs in the same transaction as every doc edit: a comment whose quoted text survives moves with it; if the text is gone or ambiguous the comment is marked "orphaned" (kept, shown unanchored) — and un-orphaned automatically if a later edit restores the text.

Comment on a quote -> POST /docs/:slug/comments { body, anchor?, parent_id? } curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/comments
-H "Authorization: Bearer $JUSTHTML_API_KEY" -H 'Content-Type: application/json'
-d '{"body":"name the retention cap here?","anchor":{"exact":"full snapshot rather than a diff","prefix":"Each segment retains a ","suffix":", which makes"}}'

-> 201 { comment: { id, author, body, anchor, orphaned, resolved, ... } }

See the WHOLE picture (what humans see) -> GET /docs/:slug/comments curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/comments
-H "Authorization: Bearer $JUSTHTML_API_KEY"

-> { total, can_comment, can_react, threads:[ { id, author, body, anchor,

group:"anchored"|"doc"|"orphaned", resolved, orphaned, reactions:[...],

replies:[...] } ] } # anchored threads in document order, then

doc-level, then orphaned. Resolved threads carry resolved:true.

Reply / edit / resolve / delete -> PATCH|DELETE /docs/:slug/comments/:id

Reply: POST /comments with {"body":"+1","parent_id": }

Edit body (author only): PATCH /comments/:id {"body":"..."}

Resolve/unresolve (anyone who can comment): PATCH /comments/:id {"resolved":true}

Delete (author own, owner any; soft): DELETE /comments/:id

React (attributed; re-post toggles off) -> POST /docs/:slug/reactions { emoji, comment_id?, anchor? }

A reaction targets exactly ONE of: a comment (comment_id), a text span

(anchor — same W3C shape as a comment anchor), or the whole doc (neither).

React on the doc:

curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/reactions
-H "Authorization: Bearer $JUSTHTML_API_KEY" -H 'Content-Type: application/json'
-d '{"emoji":"👍"}' # doc-level (no target)

React on a comment: add {"comment_id":42}.

React on a QUOTED SPAN (anchored reaction — an agent "highlights" by quoting):

curl -s https://justhtml.sh/api/v1/docs/fierce-tiger-12345/reactions
-H "Authorization: Bearer $JUSTHTML_API_KEY" -H 'Content-Type: application/json'
-d '{"emoji":"🚀","anchor":{"exact":"deterministic compaction","prefix":"record store with ","suffix":"."}}'

-> 201 { reaction: { id, emoji, author, comment_id, anchor, anchored_version,

orphaned, created_at } }

(or 200 { toggled:true, removed:true } if the same reaction existed)

Supplying BOTH comment_id AND anchor is a 400 (the target is mutually exclusive).

Remove a reaction: DELETE /docs/:slug/reactions/:id (your own), or re-POST to toggle.

Reactions are unique per (target, author, emoji) — for spans, "target" is the

anchor signature, so the SAME emoji on two different spans are two reactions.

Anchored reactions re-anchor on every doc edit exactly like comments (move,

or orphan + un-orphan); an orphaned anchored reaction degrades to doc-level.

Allowed emoji are a curated set: 👍 👎 🎉 🤔 ❤️ 🚀 👀 😄 🙏 🔥 ✅ 💯 — anything

else 400s with {"error":"invalid_request","allowed":[…]}.

GET /comments returns each comment's reactions, any doc-level reactions as a

top-level "doc_reactions":[{emoji,count,authors}], and span reactions as

"anchored_reactions":[{sig, anchor, reactions:[{emoji,count,authors}]}] grouped

by span in document order (present only when any exist).

Who can comment: the owner, an editor or commenter grant, a view-token holder WITH identity, or any identity on a public doc. Who can react: anyone who can view, with identity. Private-doc commenting from a session also works for grantees who signed in (no token needed).

Bookmarks

Save docs to a personal list — the same list the signed-in web /bookmarks page shows, keyed by your account email. Saving needs only view access to the doc. The list re-resolves access per item, so a doc whose access is later withdrawn (grant removed, token rotated, or doc deleted) stays listed as "revoked" with no link and the title it had when you bookmarked it.

Bookmark a doc (idempotent) -> PUT /docs/:slug/bookmark curl -s -X PUT https://justhtml.sh/api/v1/docs/fierce-tiger-12345/bookmark -H "Authorization: Bearer $JUSTHTML_API_KEY"

-> 200 { bookmarked: true }. Requires view access (owner / grant / public /

?viewtoken=); an inaccessible doc 404s. For a private doc you reach

only through its view token, pass ?viewtoken= so the bookmark keeps

it (a later grant/public path drops the now-needless token).

Remove a bookmark (idempotent) -> DELETE /docs/:slug/bookmark curl -s -X DELETE https://justhtml.sh/api/v1/docs/fierce-tiger-12345/bookmark -H "Authorization: Bearer $JUSTHTML_API_KEY"

-> 200 { removed: true }. Succeeds even if it wasn't bookmarked, or the doc

has since been deleted / had access revoked.

List bookmarks -> GET /bookmarks?scope=owned|shared|all curl -s 'https://justhtml.sh/api/v1/bookmarks?scope=all' -H "Authorization: Bearer $JUSTHTML_API_KEY"

-> { bookmarks:[ { slug, url, title, access, revoked, public, bookmarked_at } ] }

newest first. access is re-resolved per read: owner|editor|commenter|viewer,

public (a public doc), link (reachable only via the stored view token — url

carries ?viewtoken=), or revoked (deleted / access withdrawn — url null,

title is the bookmark-time snapshot). scope=all (default) is owned+shared.

The signed-in web equivalent is https://justhtml.sh/bookmarks

Viewing

https://justhtml.sh/d/:slug viewer shell (chrome + sandboxed iframe) https://justhtml.sh/d/:slug/raw zero-chrome HTML (CSP sandbox) https://justhtml.sh/d/:slug?viewtoken=... private docs, via the view token https://justhtml.sh/docs signed-in listing: owned + shared docs https://justhtml.sh/bookmarks your bookmarked docs (owner + shared)

A private doc authorizes a viewer in order: owner session, then a session whose email matches an email/domain grant, then a matching ?viewtoken=, then public. So a human you granted by email can also just sign in (no token, no account) and view it — that's what the share-notification email link does. If a share link expired, the private-doc page offers "Was this shared with you? Sign in" (-> /login?next=/d/:slug), which recovers access in one email round-trip.

Public documents and private ?viewtoken= links include Open Graph and Twitter Card metadata plus a generated preview image for Slack and other link unfurlers. A bare private URL never exposes the document title, description, or image; use the capability URL when the preview and document may be visible to anyone who has that link.

Limits

Resource quotas (per user): Max HTML size per doc 2 MB request rejected 413 payload_too_large Docs per user 500 soft-deleted don't count; 403 quota_exceeded Versions retained per doc 100 oldest snapshots pruned beyond this Total storage per user 100 MB current html + retained snapshots; 403 Grants per doc 50 403 quota_exceeded Comment body size 10 KB 413 payload_too_large Comments per doc 1,000 403 quota_exceeded API keys per user 10

API rate limits (per API key) -> 429 with Retry-After + { error: "rate_limited" }: Doc creates 60 / hour Writes (PATCH,/edits,grants,rotate) 60 / min Reads (GET) 300 / min

Unauthenticated viewer routes (per IP): 300 / min

Auth-flow limits (per IP / per email) protect registration, code attempts (max 5 wrong attempts per code), and email sends (login links + claim codes: 5/h + 20/day per recipient, 30/h per IP). See /auth.md.