Goal: keep an agent’s configuration, working memory, and action history in the primitives that fit each best, and use versioned reads to inspect what the agent believed at an earlier point.

Prerequisites: the strata binary on your PATH. Commands write to a durable directory (./agent) that each invocation reopens.

1. Pin configuration in KV

Flat, rarely-changing settings belong in the key-value store.

strata ./agent kv put config:model tinyllama
strata ./agent kv put config:max_steps 8

created config:model applied=true
created config:max_steps applied=true

2. Initialize working memory as a JSON document

Structured, evolving state belongs in a JSON document you can patch by path.

strata ./agent json set agent '$' '{"status":"planning","step":0,"scratchpad":[]}'

created agent applied=true

3. Advance the run

Each step patches memory and appends to the action log. The event log is your append-only audit trail.

strata ./agent event append tool_call '{"step":0,"tool":"web_search","query":"strata database"}'
strata ./agent json set agent '$.status' '"acting"'
strata ./agent event append tool_result '{"step":0,"status":"ok","hits":3}'
strata ./agent json set agent '$.step' '1'
strata ./agent event append tool_call '{"step":1,"tool":"summarize"}'
strata ./agent json set agent '$.step' '2'
strata ./agent json set agent '$.status' '"done"'

Each json set prints updated agent applied=true; each event append prints created applied=true.

4. Read the current state

strata ./agent --raw kv get config:model
strata ./agent --raw json get agent '$'
strata ./agent event count

tinyllama
{"scratchpad":[],"status":"done","step":2}
3

5. Inspect an earlier state

Every write carries a commit timestamp. List the document’s history, then read --as-of any of those timestamps to see the exact memory at that point — a rollback-style inspection with no rollback.

strata ./agent json history agent
strata ./agent --raw json get agent '$' --as-of 5
strata ./agent --raw json get agent '$' --as-of 9

{"document_version":5,"timestamp":12,"tombstone":false,"value":{"scratchpad":[],"status":"done","step":2},"version":12}
{"document_version":4,"timestamp":11,"tombstone":false,"value":{"scratchpad":[],"status":"acting","step":2},"version":11}
{"document_version":3,"timestamp":9,"tombstone":false,"value":{"scratchpad":[],"status":"acting","step":1},"version":9}
{"document_version":2,"timestamp":7,"tombstone":false,"value":{"scratchpad":[],"status":"acting","step":0},"version":7}
{"document_version":1,"timestamp":5,"tombstone":false,"value":{"scratchpad":[],"status":"planning","step":0},"version":5}
{"scratchpad":[],"status":"planning","step":0}
{"scratchpad":[],"status":"acting","step":1}

Why this works

Each primitive carries its own version history, so you never overwrite the past — you append to it. Config lives in KV, evolving memory in a JSON document, and every action in the event log. Because reads accept a commit timestamp via --as-of, “what did the agent know at step 1” is one query, not a reconstruction. When you need to branch from an earlier point rather than just read it, fork the branch at that version — see A/B Testing with Branches.