As a reader of Simon's work, I can speculate an answer here.
All "designing agentic loops" is context engineering, but not all context engineering is designing agentic loops. He's specifically talking about instructing the model to run and iterate against an evaluation step. Sure, that instruction will end up in the context, but he's describing creating a context for a specific behavior that allows an agent to be more effective working on its own.
Of course, it'll be interesting to see if future models are taught to create their own agentic loops with evaluation steps/tests, much as models were taught to do their own chain of thought.
Context engineering is about making sure you've stuffed the context with all of the necessary information - relevant library documentation and examples and suchlike.
Design the agentic loop is about picking the right tools to be provided to the model. The tool descriptions may go in the context but you also need to provide the right implementations of them.
Reason I felt like they are closely connected are because for designing tools for lets say coding agents, you have to be thoughful of context engineering.
Eg linear MCP is notorious for giving large JSONs which quickly fill up context and hard for model to understand. So tools need to be designed slightly differently for agents keeping context engineering in mind compared to how you design them for humans.
Context engineering feels like more central and first-principle approach of designing tools, agent loops.
They feel pretty closely connected. For instance: in an agent loop over a series of tool calls, which tool results should stay resident in the context, which should be summarized, which should be committed to a tool-searchable "memory", and which should be discarded? All context engineering questions and all kind of fundamental to the agent loop.
andrewacove|5 months ago
All "designing agentic loops" is context engineering, but not all context engineering is designing agentic loops. He's specifically talking about instructing the model to run and iterate against an evaluation step. Sure, that instruction will end up in the context, but he's describing creating a context for a specific behavior that allows an agent to be more effective working on its own.
Of course, it'll be interesting to see if future models are taught to create their own agentic loops with evaluation steps/tests, much as models were taught to do their own chain of thought.
simonw|5 months ago
Context engineering is about making sure you've stuffed the context with all of the necessary information - relevant library documentation and examples and suchlike.
Design the agentic loop is about picking the right tools to be provided to the model. The tool descriptions may go in the context but you also need to provide the right implementations of them.
prats226|5 months ago
Eg linear MCP is notorious for giving large JSONs which quickly fill up context and hard for model to understand. So tools need to be designed slightly differently for agents keeping context engineering in mind compared to how you design them for humans.
Context engineering feels like more central and first-principle approach of designing tools, agent loops.
tptacek|5 months ago
andrewacove|5 months ago