1. What is the nature and description of the request?

Customer would like to be able to easily monitor status of each job executed within a workflow ( the ones executed by the worfklow, and those exected by a sub-workflow, etc...). Today, they have to check each job and merge results. Now the would like to have a summary on the workflow  webui and with the api 
/api/workflow_jobs/<id>/summary_jobs
2. Why does the customer need this? (List the business requirements here)

Facilitate monitoring result, especially for big workflow (they have workflow which are calling dozens of sub-workflows, each of them calling some jobs). Having a uniq endpoint to have the result of all executions could be a game changer.

3. How would you like to achieve this? (List the functional requirements here)

Like for playbook execution, adding at the end of the source worfklow the summary in this form
Workflow 1 have 2 Workflow nodes A and B
WF node A launch the playbook on host C +D
WF node B launch the playbook on host E + F

At the end of WF we want to have in /api/workflow_jobs/<id>/summary_jobs

wf_nodeA
host C ok: 2, failed:5, skipped2 ....
host D ok: 0, unreachable: 1 ...
wf_nodeB
host E ok:4, failed: 3..
host F ok:8 changed: 3 ...
 

4. List any affected known dependencies: Doc, UI etc..

UI, API