Decision Log
Persist the agent's reasoning trace alongside its actions so post-hoc review can explain the *why*, not just the *what*.
Intent & Description
🎯 Intent
Persist the agent’s reasoning trace alongside its actions so post-hoc review can explain why the agent did something, not just what it did.
📋 Context
You already keep an action log — which tool was called, which output was returned. But when a trading agent opens a bad position or a support agent issues a wrong refund, investigators need the reasoning behind the action. Action logs alone leave you blind.
💡 Solution
Persist reasoning at a chosen granularity (full trace, key decisions, or summary). Link each action in the provenance ledger to its reasoning trace. Index by request ID and timestamp for fast retrieval.
Real-world Use Case
- Action-only logs leave you unable to explain why the agent did something.
- Reasoning at some granularity (full trace, key decisions, summary) can be captured and stored cheaply.
- Post-hoc review or debugging routinely needs to consult the reasoning chain.
Source
📌 TL;DR
Log the reasoning, not just the actions — when something goes wrong, you need the agent’s thought process, not a list of API calls.
Advantages
- Debugging speed jumps — you see the why immediately, not just the what.
- User-facing explanations become possible (“the agent did X because it concluded Y”).
Disadvantages
- Storage and privacy implications — reasoning traces can contain sensitive context.
- Trace tampering (agent rewriting its own trace) defeats the purpose — append-only storage is required.