status: complete audience: both chapter: 05 last_updated: 2026-04 contributors: [alexwill87, claude-cockpit] lang: en

5.5 -- Memory Drift

Context

Your agent's memory accumulates information over time. Some becomes obsolete, some contradicts itself, some has become false without anyone noticing. This is memory drift.

Steinberg compares it to a desk: if you never organize, important documents get lost under expired papers.

Symptoms of Drift

You have a drift problem when:

• The agent mentions a project you finished 2 months ago.
• The agent uses an old workflow that has been replaced.
• The agent gives contradictory information in two close responses.
• The agent "remembers" a decision that was canceled.
• The agent repeats information, phrasing it differently each time (sign of redundancy).

Types of Drift

Obsolescence

The information was true but no longer is.

Memory: "The cockpit project uses Express.js"
Reality: you migrated to Fastify 3 weeks ago.

Contradiction

Two pieces of information contradict each other.

Memory file A: "Backups are daily"
Memory file B: "Backups are weekly"

Inflation

The same information is stored in 5 different forms. The agent no longer knows which one to use.

File 1: "The user prefers informal speech"
File 2: "Use informal speech, not formal"
File 3: "Informal communication, use tu"

Memorized Hallucination

The agent once "invented" information and stored it as fact.

Memory: "The server has 16 GB of RAM"
Reality: it has 8.

Periodic Cleanup

Frequency

• Monthly: quick scan (15 minutes).
• Quarterly: deep cleanup (1 hour).
• After each completed project: remove project context.

Scan Prompt

Read all your memory and context files.
For each factual piece of information, indicate:
- [OK]: still true and useful
- [OBSOLETE]: no longer true
- [DOUBT]: you're not sure, needs verification with me
- [REDUNDANT]: says the same thing as another entry

List the results. We'll clean up together.

Cleanup Process

1. Run the scan prompt.
2. Review the results with the agent.
3. Delete the [OBSOLETE] entries.
4. Merge [REDUNDANT] entries into a single one.
5. Verify the [DOUBT] entries — correct or delete.
6. Save the cleaned version.

Night Consolidation

Steinberg's concept: at the end of each day (or week), the agent consolidates what it learned.

Summary of the day:
- What new information did you learn today?
- Does it contradict anything in your memory?
- What information in memory was confirmed by today?

Propose the necessary memory updates.

It doesn't take long. 2 minutes at the end of the day. But it prevents drift from accumulating.

Voluntary Forgetting

Sometimes the right action is to delete from memory. Not because it's false, but because it's no longer useful.

Candidates for forgetting:

• Details of a completed project (keep only lessons learned).
• Intermediate decisions that were replaced by the final decision.
• Temporary context ("this week I'm working on X").
• Documented trials and errors that are no longer relevant.

Voluntary forgetting reduces noise and token cost. Less memory = faster reads = more accurate responses.

Common Mistakes

Never clean up. Memory grows, contradictions accumulate, response quality drops. You blame the agent when it's actually polluted memory.

Delete everything. Radical cleanup: you erase all memory. The agent starts from scratch and loses all useful context. Clean surgically.

Trust the scan without verifying. The agent marks [OK] on obsolete information because it doesn't know it changed. Verify critical facts yourself.

No memory versioning. You delete information and need it 2 weeks later. Keep a backup before each cleanup.

Steps

1. Run the scan prompt on your memory.
2. Review the results: OBSOLETE, DOUBT, REDUNDANT.
3. Save the current version of memory (backup).
4. Clean up: delete, merge, correct.
5. Test: does the agent give more accurate responses?
6. Schedule the next cleanup (monthly).

Verification

• [ ] A memory scan has been done in the last month.
• [ ] Obsolete information is deleted.
• [ ] Redundancies are merged into a single entry.
• [ ] A memory backup exists before each cleanup.
• [ ] Night consolidation is practiced (daily or weekly).