## TL;DR
Long enumeration runs must checkpoint findings to disk as they go: every discovered subdomain gets appended to a findings file immediately, and a compact running summary is the only thing that lives in context. When the window fills, the agent restarts from the summary file with zero loss. Findings in context are volatile; findings on disk are real.

```text
agent hit context limit after 6 hours of authorized subdomain enumeration; findings failed to save
```

## Use this when
- A multi-hour enumeration run ended with no saved findings file.
- The agent's context filled up and it started dropping earlier results.
- You run agent-driven subdomain enumeration on authorized domains.

## Not for this skill when
- The enumeration tools found nothing. Then there is nothing to save.
- The run failed in the first minutes. That is a tooling problem, not a context problem.
- The domains are outside your authorized engagement. Do not enumerate them.

## Steps
1. Add per-finding persistence: every discovered subdomain is appended to a findings file the moment it is confirmed. Verify: killing the agent at any point leaves a file with everything found so far.
2. Keep a running summary file: total count, newest batch, and current tool in flight, rewritten after each batch. Verify: the summary file alone is enough to resume.
3. Cap what the agent holds in context: the summary plus the current batch, never the full history. Verify: context usage stays flat as the run grows.
4. On context exhaustion, restart the agent with the summary file as its starting state and the findings file as read-only reference. Verify: the resumed run discovers no duplicates of already-saved names.
5. At the end, dedupe the findings file and write the final asset list. Verify: the final count matches the summary's total.

## Variant phrasings
### long enumeration run lost findings context limit
Common phrasing.
### agent checkpoint subdomain enumeration to disk
Workflow phrasing.
### 6 hour recon run no saved results
Symptom-level search.

Compatibility: any enumeration tooling under agent control. The checkpoint pattern is tool-agnostic.

## Why it happens
Agents treat context as storage, but context is working memory with a hard ceiling. Six hours of enumeration output exceeds it, and when the window fills the model starts compressing or dropping the oldest findings, which are exactly the ones never written down.

## Edge cases / pitfalls
- Appending per finding is cheap; rewriting the whole file per finding is not. Append findings, rewrite only the small summary.
- Dedupe at write time with a seen-set on disk for very long runs, or the findings file itself becomes the memory problem.
- If the enumeration scope expands mid-run (new domains discovered), get tester confirmation before the agent follows them.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_1vFVgk1_RmUIB-C4ge7z6A