A durable interaction record
Sessions contain user input, assistant responses, tool calls, and outputs in chronological order.
Sessions & Memory
Sessions and Memory for Harness Engineer Systems
Sessions and memory solve different problems. Sessions preserve process and chronology, while memory preserves reusable value across time. Harness Engineer work depends on treating them as distinct layers.
- Clarify the difference between session logs and context payloads
- Explain why memory should be its own subsystem
- Show how state, extraction, and retrieval work together
Signal Layer Harness Engineer Index
Session parts Events + State
Memory role Long-term value
Design goal Continuity
What a session is
A place for working state
They can also store temporary state or scratchpad-style structures that support the active task.
Not the same as context
A full session should rarely be sent to the model unchanged. Context is a filtered payload, not raw storage.
Why memory is separate
It enables cross-session continuity
Without memory, useful preferences and long-term facts stay trapped inside isolated conversations.
It supports multi-agent interoperability
Different agents may keep private histories, but they can still share a memory layer with canonical information.
It reduces repeated work
Memory retrieval can bring back what matters without replaying every prior conversation.
Key memory manager responsibilities
Extraction
Identify what is meaningful enough to become memory.
Consolidation
Merge or replace overlapping facts so the memory layer evolves instead of bloating.
Retrieval
Return the right memories at the right time and place them where they help reasoning the most.
Frequently Asked Questions
These questions cover high-frequency search intent around Harness Engineer, context engineering, sessions, and memory.
What is the difference between session history and context?
Session history is the full persistent record, while context is the curated subset sent to the model for a specific step.
Does memory always require a vector database?
No. Vector search is common, but structured stores, knowledge graphs, and hybrid systems can also be appropriate.
Next Step
Want help designing sessions and memory together?
We can help structure session persistence, memory generation, retrieval placement, and compaction rules.