diff --git a/README.md b/README.md
index 2ce5316..02521c2 100644
--- a/README.md
+++ b/README.md
@@ -98,10 +98,14 @@ subsequent requests automatically:
(Result.Error e) (IO.errorln &e)))
```
-The jar handles domain matching (RFC 6265 suffix rules), path matching,
-Secure flag enforcement, and expiry. Cookies are deduplicated by
-name+domain+path. During redirects, cookies from every hop are stored and
-re-applied for each new URL.
+The jar follows RFC 6265 §5.3 and §5.4. A cookie that arrives with no
+`Domain` attribute is host-only: it goes back to the host that set it and to
+no subdomain. A `Domain` attribute the responding host does not domain-match
+is rejected outright, and so is a single-label one such as `Domain=com`. On
+top of that the jar enforces path matching, the `Secure` flag, and expiry;
+cookies are deduplicated by name+domain+path and serialized longest path
+first. During redirects, cookies from every hop are stored and re-applied for
+each new URL.
### Multipart uploads
@@ -207,9 +211,9 @@ given.
| Function | Purpose |
|----------|---------|
| `CookieJar.create` | Create an empty jar |
-| `CookieJar.store! jar cookie` | Store a cookie, replacing duplicates by name+domain+path |
-| `CookieJar.store-response! jar response url` | Store cookies from a response, defaulting domain from URL |
-| `CookieJar.matching jar url` | Return cookies matching the URL by domain, path, security, and expiry |
+| `CookieJar.store! jar cookie` | Store a cookie as a domain cookie, replacing duplicates by name+domain+path |
+| `CookieJar.store-response! jar response url` | Store a response's cookies, applying RFC 6265 §5.3's origin checks |
+| `CookieJar.matching jar url` | Return cookies matching the URL by domain, path, security, and expiry, longest path first |
| `CookieJar.cookie-header jar url` | Build a `Cookie` header value, or `Nothing` if no cookies match |
| `CookieJar.apply-to-headers jar url headers` | Add a `Cookie` header to the headers map |
| `CookieJar.size jar` | Number of stored cookies |
diff --git a/docs/Client.html b/docs/Client.html
index 2674529..eb8ba00 100644
--- a/docs/Client.html
+++ b/docs/Client.html
@@ -32,6 +32,11 @@
CookieJar
+
is a stored cookie together with RFC 6265 §5.3’s
+host-only-flag, which is set when the cookie arrived without a Domain
+attribute and may therefore only go back to the host that set it.