Document 'filter' field for _replicate endpoint.
diff --git a/src/api/server/common.rst b/src/api/server/common.rst
index 97f838a..ee0f352 100644
--- a/src/api/server/common.rst
+++ b/src/api/server/common.rst
@@ -361,6 +361,7 @@
:<json boolean create_target: Creates the target database.
Required administrator's privileges on target server.
:<json array doc_ids: Array of document IDs to be synchronized
+ :<json string filter: The name of a :ref:`filter function <filterfun>`.
:<json string proxy: Address of a proxy server through which replication
should occur (protocol can be "http" or "socks5")
:<json string source: Source database name or URL