diff --git a/docs/api/context.md b/docs/api/context.md
index 045211f..d9dd193 100644
--- a/docs/api/context.md
+++ b/docs/api/context.md
@@ -74,12 +74,14 @@ koa uses the [cookies](https://github.com/jed/cookies) module where options are
 
   Set cookie `name` to `value` with `options`:
 
+ - `maxAge` a number representing the milliseconds from Date.now() for expiry
  - `signed` sign the cookie value
  - `expires` a `Date` for cookie expiration
  - `path` cookie path, `/'` by default
  - `domain` cookie domain
  - `secure` secure cookie
  - `httpOnly` server-accessible cookie, __true__ by default
+ - `overwrite` a boolean indicating whether to overwrite previously set cookies of the same name (__false__ by default). If this is true, all cookies set during the same request with the same name (regardless of path or domain) are filtered out of the Set-Cookie header when setting this cookie.
 
 koa uses the [cookies](https://github.com/jed/cookies) module where options are simply passed.