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+# SkillOpt-Sleep — plugin load-test (fresh examples)
+
+This records an actual end-to-end load-test of all three plugin shells on a
+**brand-new example** (not the gbrain benchmark seeds), run on 2026-06-08.
+
+## The fresh persona
+
+A data analyst whose SQL queries must always include a `LIMIT` clause — built
+from scratch for this test. Two forms were used:
+
+1. **Real transcripts** — crafted Claude Code session JSONL where the analyst
+   asks for SQL, the agent forgets `LIMIT`, and the user complains ("you forgot
+   a LIMIT again", "always cap results"). This exercises the real
+   harvest → mine pipeline.
+2. **Checkable tasks** — the same intent with a rule judge
+   (`regex: (?i)LIMIT\s+100`), so the optimizer can be scored on whether future
+   SQL follows the house rule.
+
+## Results
+
+### Shell plumbing (all three drive the engine)
+
+| Shell | What was run | Result |
+|---|---|---|
+| **Claude Code** (`scripts/sleep.sh`) | `harvest`, full `run`, `adopt` | harvest found 2 sessions → 2 tasks; `run` staged a proposal; `adopt` honored the safety contract (no live change when nothing was accepted) |
+| **Codex** (`install.sh` + shared runner) | `install.sh` into a temp HOME | placed `~/.codex/prompts/sleep.md` and `~/.agents/skills/skillopt-sleep/SKILL.md` correctly |
+| **Copilot** (`mcp_server.py`) | `initialize` → `tools/list` → `tools/call sleep_harvest` | 5 tools listed; `sleep_harvest` returned real engine output (2 sessions → 2 tasks) |
+
+### Genuine improvement (real model, fresh persona)
+
+Optimizer **Claude Sonnet 4.6** → target **Claude Haiku 4.5**, 3-way split
+(5 train / 2 val / 5 test), scored on the held-out **test** queries; and the same
+fresh persona self-optimized on **Codex**:
+
+| Backend | Held-out **test** (fraction of SQL with `LIMIT 100`) before → after |
+|---|---|
+| Claude (Sonnet → Haiku) | **0.00 → 1.00** |
+| Codex | **0.00 → 1.00** |
+
+In one night each optimizer wrote, into the protected learned block, a rule like:
+
+> *"OVERRIDE: Every SQL query you generate MUST include `LIMIT 100` …"* (Claude)
+> *"Hard requirement: every SQL query response must include …"* (Codex)
+
+and the target then applied it to the **unseen** test queries. This is the whole
+claim on a task family the engine had never seen: it learned the user's house
+rule from their failures and generalized it — confirmed on both backends.
+
+## An honest finding from load-testing
+
+The **first** attempt used `val_fraction=0.34, test_fraction=0.34`, which left
+only **1 train task** for an 8-task set — too little signal — so reflect produced
+nothing and the night was a no-op (val already 0.75). Re-balancing the split to a
+real train pool (5 train) fixed it and produced the 0 → 1.00 result above. This
+is exactly the kind of issue that only surfaces when you actually run the thing,
+and it motivates a future guardrail: warn when the train pool is too small for
+the chosen split fractions.
+
+## Reproduce
+
+The checkable persona run (real Claude):
+
+```python
+# see the snippet in docs/sleep/plugin_load_test.md history, or run:
+python -m skillopt_sleep.experiments.run_experiment --persona programmer --assert-improves  # deterministic
+```
+
+Shell checks:
+
+```bash
+# Copilot MCP server
+printf '%s\n' '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' \
+  | SKILLOPT_SLEEP_REPO="$(pwd)" python3 plugins/copilot/mcp_server.py
+# Codex installer (into a throwaway HOME)
+HOME=$(mktemp -d) bash plugins/codex/install.sh
+```