# Agentic Ai Engineering
All Agentic Ai Engineering notes →1. Context Assembly
How the final prompt an agent actually sends gets built from disparate sources — system instructions, retrieved chunks, memory, tool schemas, and conversation history — and why where a piece sits changes how much the model attends to it.
2. Context Ranking
Covers scoring and ordering already-selected context fragments -- retrieved chunks, memory items, tool output, and prior turns -- by semantic similarity, recency, source authority, and prior usefulness before they compete for a fixed token budget, and the near-duplicate crowding failure mode that ranking by similarity alone produces.
3. Memory Selection
The policy layer between memory retrieval and context assembly -- deciding which of the memories retrieval surfaced are actually worth spending tokens on for this specific turn, and why over-including memory is its own failure mode, not just a cost line item.
4. Prompt Budgets
Allocating a fixed token budget across system prompt, tool schemas, conversation history, retrieved context, and memory -- concrete allocation math, what happens when the budget is exceeded, and why percentage-based budgets break the moment you swap context-window sizes.
5. Retrieval Policies
The decision layer that sits in front of Part 05's retrieval mechanics — whether to retrieve at all, how much to pull for a given query, and from which knowledge source, what over- and under-retrieving each cost you, and how Agentic RAG relocates the whole policy into the model's own reasoning loop.
6. Context Compression
Summarization, extractive pruning, and structured compression for fitting more signal into less context — and the risk every one of them shares: silently dropping the one detail the model actually needed this turn.
7. Prompt Compilers
Covers the emerging, deliberately-not-yet-standardized idea of treating context assembly as a compilation step -- a declarative spec of what a turn needs compiled through a coherent pass of ranking, budgeting, and compression -- instead of hand-assembled string concatenation that degrades as context sources multiply.