Philadelphia Terminal Client can run scripts nowadays. For testing FIX acceptors, an expect command would be useful. The syntax of the command could be similar to the syntax of the send command. For example:

expect 35=A|98=0|108=30

On the other hand, it should also be possible to skip the expectation for a specific field value, such as the OrderID(37) and ExecID(17) values here:
`

Section 7.3.1.1 states that

"The Sequence, Context, EstablishmentAck and Retransmission messages are sequence forming. They turn the message flow into a sequenced mode since they have the next implicit sequence number."

The Establish message is not on that list. Is that omission deliberate? If it is, then the client (with a recoverable flow) would need to send a Sequence after send

From the specification:

'JSON encoding does not include a “CheckSum” field since it is unlikely to be useful at best, and likely
to be incorrect at worst (e.g. if copied over from another FIX encoding).'

The example output provided from the Java encoder includes the Checksum tag within the trailer:

...
	"Trailer":{
		"CheckSum": "041"
	}
...

Presumably, per the spec, the