In the design of the management API of a network element, we often include support for the commonly used CLIs like the CISCO style CLI and Juniper style CLI. But to support those commands, we need to know the breakdown of the commands issued into the sequence of operations on the MIB tables and objects there in. For example:
A CLI command : router bgp 4711 neighbor 3.3.3.3
And it's MIB object operations (like in SNMP) would be :
bgpRmEntIndex 4711
bgpPeerLocalAddrType unica
bgpPeerLocalAddr 2.2.2.2
bgpPeerLocalPort 179
bgpPeerRemoteAddrType uni
bgpPeerRemoteAddr 3.3.3.3
bgpPeerRemotePort 179
Is there some resource which can help us understand this breakdown?
In general on the types of devices that you mention, you will find that there is no simple mapping between CLI operations and (SNMP) operations on MIB variables. The CLIs are optimized for "user-friendly" configuration and on-line diagnostics, SNMP is optimized for giving machine-friendly access to "instrumentation", mostly for monitoring. Within large vendors (such as Cisco or Juniper) CLI and SNMP are typically developed by different specialized groups.
For something that is closer to CLIs, but more friendly towards programmatic use (API), have a look at the IETF NETCONF protocol, which provides XML-based RPC read and write access to device configuration (and state). Juniper pioneered this concept through their Junoscript APIs and later helped with defining the IETF standard, so you will find good support there. Cisco has also added NETCONF capabilities to their systems, especially the newer ones such as IOR-XR.