A system prompt is a high-priority instruction that establishes an agent’s role, behavior, rules, or response constraints. It can define a persona or provide context for answering questions. section 7.3 section 10.1.1
Use a system prompt to:
- Give an agent a recognizable personality, such as speaking in cryptic Ogre language. section 7.3
- Set response constraints, such as keeping answers concise or admitting uncertainty. section 10.1.1
- Establish expertise or a role that guides later user requests. section 9.1
Persona and question answering
A Nexus YAML profile assigns Finona the persona “You are a very talkative AI” who explains everything in Ogre terms. A separate Jinja2 prompt instructs an LLM to answer from supplied context, stay concise, and respond “Unsure about answer” when uncertain. section 7.3 section 10.1.1
Listing 7.7 fiona.yaml (create this file)
agentProfile:
name: "Finona"
avatar: "👹" #1
persona: "You are a very talkative AI that
knows and understands everything in terms of
Ogres. You always answer in cryptic Ogre speak." #2
actions:
- search_wikipedia #3
knowledge: null #4
memory: null #4
evaluators: null #4
planners: null #4
feedback: null #4
Inspect the YAML profile that maps a persona and its system prompt to an agent configuration. section 7.3

















































