I think how the game works is that you would get these random investigations where you can assign agents to. The assigned agent's skill gets checked against the required skill of said task and you would get the results come morning. If the agent assigned is not skilled enough, you fail the task.

Andre Brasillach
Strength: 1
Surveillance: 1
Social: 1

Adeline Brahe
Strength: 0
Surveillance: 1
Social: 3

Anthony Palme
Strength: 3
Surveillance: 0
Social: 1

Gerhard Merkel
Strength: 1
Surveillance: 0
Social: 3

Clark Orwell
Strength: 3
Surveillance: 1
Social: 1

Abyad Alshah
Strength: 2
Surveillance: 1
Social: 1

Catherine Hirsch
Strength: 1
Surveillance: 1
Social: 2

Henry Taggert
Strength: 1
Surveillance: 2
Social: 1

John Overton
Strength: 1
Surveillance: 3
Social: 1

Albin Arrow
Strength: 2
Surveillance: 1
Social: 0

Eric Hoffmann
Strength: 0
Surveillance: 1
Social: 2

Well, the main issue with this game is that the agent files does a poor job at telling you what the agent is good at. When you get an investigation, however, you can clearly see what skills each of the options require and you can therefore reference this table to assign the best agent for the task.

For example:
When it says interrogate witness, you want to assign someone with good social skill
When it says tail someone, you want to assign someone with good surveillance skill
When it says beat someone, you want to assign someone with good strength skill

I found the data at:
Steam\steamapps\common\For the People\game\documents\agents.json