# SxCP Eval Loop

This loop is for tuning the SxCP generator toward stronger Krea2 images.
ComfyUI sends a generated prompt, image, and seed to Codex, Codex analyzes the
result, then sends back exactly one edited prompt for the next A/B test.
Confirmed findings become either generator changes or durable prompt rules in
[`krea2-prompt-guide.md`](krea2-prompt-guide.md).

## Channels

- `sxcp_eval_in`: ComfyUI to Codex. Contains the prompt text, image path, and
  seed.
- `sxcp_eval_out`: Codex to ComfyUI. Prompt-only text plus the same seed through
  the MCP signal when supported. Do not put analysis here.
- `sxcp_eval_log`: optional analysis/log channel.

## Manual Loop

Start the helper after sending a test prompt:

```bash
tools/sxcp_eval_loop.sh 3
```

Every three minutes it prints a structured request asking Codex to:

1. Pull `sxcp_eval_in`.
2. Record the emitted seed.
3. Inspect the image.
4. Compare it to the prompt and previous edit.
5. Push one prompt-only edit to `sxcp_eval_out`, preserving the same seed through
   the MCP signal when available.
6. Classify the finding as prompt-only, prompt-guide rule, or generator fix.
7. Change generator code/data only when the issue is systemic.
8. Record the finding and update the Krea2 prompt guide when a rule is confirmed.

Runtime logs are written under `.sxcp_eval/` and ignored by git.

## Optional Command Hook

If you have a one-shot Codex command you want to run automatically, set:

```bash
SXCP_EVAL_CODEX_CMD="codex exec" tools/sxcp_eval_loop.sh 3
```

The request is sent on stdin. The command also receives:

- `SXCP_EVAL_IN_CHANNEL`
- `SXCP_EVAL_OUT_CHANNEL`
- `SXCP_EVAL_LOG_CHANNEL`
- `SXCP_EVAL_GUIDE_FILE`
- `SXCP_EVAL_REQUEST_FILE`
- `SXCP_EVAL_CYCLE_DIR`
- `SXCP_EVAL_CYCLE`

## Evaluation Axes

- Identity consistency
- Outfit continuity
- Pose/action accuracy
- Camera compliance
- Location coherence
- Crop/framing
- Prompt noise/repetition
- Model confusion tokens
- Seed control/reproducibility
- Overall Krea2 image usefulness

## Seed Contract

The seed is transport metadata, not prompt text. When the graph emits a seed, an
A/B wording test should reuse that exact seed so the image difference mostly
comes from wording, not sampling randomness. If a payload has no seed, mark that
cycle as uncontrolled and avoid turning the result into a durable generator rule
without another controlled run.

## Generator Fix Rule

Only edit the generator when the image shows a repeatable, systemic prompt
failure. Examples:

- Selfie wording overrides orbit camera.
- Clothing continuity loses the selected softcore outfit.
- POV wording makes the off-camera participant the visual subject.
- Location camera layout inserts foreground anchors in the wrong place.

For one-off model drift, send a cleaner prompt to `sxcp_eval_out` and keep the
generator unchanged. For repeated prompt behavior, update the generator and add
the rule to `docs/krea2-prompt-guide.md`.