Here is a list of all documented files with brief descriptions:

proton
codec
common.hpp	Unsettled API - Shared codec functions
decoder.hpp	Unsettled API - A stream-like decoder from AMQP bytes to C++ values.
deque.hpp	Unsettled API - Enable conversions between proton::value and std::deque
encoder.hpp	Unsettled API - A stream-like encoder from C++ values to AMQP bytes.
forward_list.hpp	Unsettled API - Enable conversions between proton::value and std::forward_list
list.hpp	Unsettled API - Enable conversions between proton::value and std::list
map.hpp	Unsettled API - Enable conversions between proton::value and std::map
unordered_map.hpp	Unsettled API - Enable conversions between proton::value and std::unordered_map
vector.hpp	Unsettled API - Enable conversions between proton::value and std::vector
io
connection_driver.hpp	Unsettled API - An AMQP driver for a single connection.
annotation_key.hpp	A key for use with AMQP annotation maps.
binary.hpp	Arbitrary binary data.
byte_array.hpp	Arbitrary fixed-size data.
connect_config.hpp
connection.hpp	A connection to a remote AMQP peer.
connection_options.hpp	Options for creating a connection.
container.hpp	A top-level container of connections, sessions, and links.
decimal.hpp	AMQP decimal types
default_container.hpp	Deprecated - Use the API in container.hpp
delivery.hpp	A received message.
delivery_mode.hpp	The message delivery policy to establish when opening a link.
duration.hpp	A span of time in milliseconds.
endpoint.hpp	The base class for session, connection, and link.
error.hpp	The base Proton error.
error_condition.hpp	Describes an endpoint error state.
function.hpp	Deprecated - Use the API in work_queue.hpp
fwd.hpp	Forward declarations
link.hpp	A named channel for sending or receiving messages.
listen_handler.hpp	Unsettled API - A handler for incoming connections.
listener.hpp	A listener for incoming connections.
map.hpp	A collection of key-value pairs.
message.hpp	An AMQP message.
message_id.hpp	An AMQP message ID.
messaging_handler.hpp	Handler for Proton messaging events.
namespaces.hpp	Namespace declarations
null.hpp	The type of the AMQP null value.
receiver.hpp	A channel for receiving messages.
receiver_options.hpp	Options for creating a receiver.
reconnect_options.hpp	Options for reconnect and failover after connection loss.
returned.hpp	A return type for container methods.
sasl.hpp	SASL information.
scalar.hpp	A holder for an instance of any scalar AMQP type.
scalar_base.hpp	The base class for scalar types.
sender.hpp	A channel for sending messages.
sender_options.hpp	Options for creating a sender.
session.hpp	A container of senders and receivers.
session_options.hpp	Options for creating a session.
source.hpp	A point of origin for messages.
source_options.hpp	Options for creating a source node for a sender or receiver.
ssl.hpp	SSL information.
symbol.hpp	A string that represents the AMQP symbol type.
target.hpp	A destination for messages.
target_options.hpp	Options for creating a target node for a sender or receiver.
terminus.hpp	One end of a link, either a source or a target.
thread_safe.hpp	Deprecated - No longer used
timestamp.hpp	A 64-bit timestamp in milliseconds since the Unix epoch.
tracing.hpp
tracker.hpp	A tracker for a sent message.
transfer.hpp	The base class for delivery and tracker.
transport.hpp	A network channel supporting an AMQP connection.
type_id.hpp	Type IDs for AMQP data types
types.hpp	Proton types used to represent AMQP types
types_fwd.hpp	Forward declarations for Proton types used to represent AMQP types
url.hpp	Deprecated - Use a third-party URL library
uuid.hpp	A 16-byte universally unique identifier.
value.hpp	A holder for any AMQP value, simple or complex.
work_queue.hpp	Unsettled API - A context for thread-safe execution of work.