and server advertised. As a consequence of these rules, server MUST
NOT advertise capabilities it does not understand.
-The 'report-status' and 'delete-refs' capabilities are sent and
+The 'report-status', 'delete-refs', and 'quiet' capabilities are sent and
recognized by the receive-pack (push to server) process.
-The 'ofs-delta' capability is sent and recognized by both upload-pack
-and receive-pack protocols.
+The 'ofs-delta' and 'side-band-64k' capabilities are sent and recognized
+by both upload-pack and receive-pack protocols. The 'agent' capability
+may optionally be sent in both protocols.
All other capabilities are only recognized by the upload-pack (fetch
from server) process.
If the client wants x,y and starts out by saying have F,S, the server
doesn't know what F,S is. Eventually the client says "have d" and
the server sends "ACK d continue" to let the client know to stop
-walking down that line (so don't send c-b-a), but its not done yet,
+walking down that line (so don't send c-b-a), but it's not done yet,
it needs a base for x. The client keeps going with S-R-Q, until a
gets reached, at which point the server has a clear base and it all
ends.
ofs-delta
---------
-Server can send, and client understand PACKv2 with delta refering to
+Server can send, and client understand PACKv2 with delta referring to
its base by position in pack rather than by an obj-id. That is, they can
send/read OBJ_OFS_DELTA (aka type 6) in a packfile.
+agent
+-----
+
+The server may optionally send a capability of the form `agent=X` to
+notify the client that the server is running version `X`. The client may
+optionally return its own agent string by responding with an `agent=Y`
+capability (but it MUST NOT do so if the server did not mention the
+agent capability). The `X` and `Y` strings may contain any printable
+ASCII characters except space (i.e., the byte range 32 < x < 127), and
+are typically of the form "package/version" (e.g., "git/1.8.3.1"). The
+agent strings are purely informative for statistics and debugging
+purposes, and MUST NOT be used to programatically assume the presence
+or absence of particular features.
+
shallow
-------
report-status
-------------
-The upload-pack process can receive a 'report-status' capability,
+The receive-pack process can receive a 'report-status' capability,
which tells it that the client wants a report of what happened after
a packfile upload and reference update. If the pushing client requests
this capability, after unpacking and updating references the server
-----------
If the server sends back the 'delete-refs' capability, it means that
-it is capable of accepting an zero-id value as the target
+it is capable of accepting a zero-id value as the target
value of a reference update. It is not sent back by the client, it
simply informs the client that it can be sent zero-id values
to delete references.
+
+quiet
+-----
+
+If the receive-pack server advertises the 'quiet' capability, it is
+capable of silencing human-readable progress output which otherwise may
+be shown when processing the received pack. A send-pack client should
+respond with the 'quiet' capability to suppress server-side progress
+reporting if the local progress reporting is also being suppressed
+(e.g., via `push -q`, or if stderr does not go to a tty).
+
+allow-tip-sha1-in-want
+----------------------
+
+If the upload-pack server advertises this capability, fetch-pack may
+send "want" lines with SHA-1s that exist at the server but are not
+advertised by upload-pack.