AI agent

• comparision

Layer What you control Simple example
Prompt engineering What you tell the model/ “Summarize this document in 5 bullets.”
Context engineering What information the model gets/ Give it the right documents, database results, memory, schemas, etc.
Harness engineering The entire environment around the model/ Give it tools, APIs, permissions, memory, validation, constraints, feedback loops, monitoring, etc.

• Agent
  Agent = Model + Harness

             ┌──────────────────────────┐
             │       HARNESS            │
             │ tools, memory, validation│
             │ orchestration, feedback  │
             │                          │
             │   ┌──────────────────┐   │
             │   │     CONTEXT      │   │
             │   │ retrieval, data, │   │
             │   │ memory, schemas  │   │
             │   │                  │   │
             │   │  ┌────────────┐  │   │
             │   │  │   PROMPT   │  │   │
             │   │  │ instructions│ │   │
             │   │  └────────────┘  │   │
             │   └──────────────────┘   │
             └──────────────────────────┘
                      ↓
                   MODEL