> ## Documentation Index
> Fetch the complete documentation index at: https://docs.51ultron.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Memory Recall

> How Ultron selects the right memories for each turn — and why it caps at 5.

Ultron doesn't inject all memories into every conversation. That would flood context with irrelevant information. Instead, a targeted recall system selects exactly the entries most relevant to the current task.

## How recall works

<Steps>
  <Step title="Side-query runs">
    Before each agent turn, a separate fast-model side-query runs against the memory store. It receives the current task objective and searches for relevant entries.
  </Step>

  <Step title="Candidates scored">
    Memory entries are ranked by semantic relevance to the current objective. Recency is a secondary factor — fresh entries score slightly higher when relevance is equal.
  </Step>

  <Step title="Deduplication applied">
    Entries that were already surfaced in recent turns are skipped. This prevents the same memory from appearing repeatedly and wasting context.
  </Step>

  <Step title="Top 5 injected">
    The 5 highest-scoring entries are injected into context before Kimi K2 sees the message. More than 5 adds noise without improving output.
  </Step>
</Steps>

## Why the cap is 5

Intuition says more context is better. In practice, it isn't.

With more than 5 memories injected, two things happen:

1. Irrelevant entries dilute the signal of relevant ones
2. Token budget fills up faster, triggering compression sooner

5 high-signal entries outperform 15 mixed-relevance entries every time.

## Memory drift defense

Before any memory entry is injected, Ultron validates it:

* File paths mentioned — do they still exist?
* Functions referenced — are they still in the codebase?
* External references — are they still current?

Stale memories that reference deleted files or outdated context are flagged or skipped rather than injected and acted on incorrectly.

<Warning>
  If Ultron says "I don't have recent information on this" when you expect it to, the relevant memory may be stale or tagged with a different topic. Use the Brain Graph to audit what's stored.
</Warning>