nexu-io/open-design · error · SystemExit

running-left mirror source image no longer exists: {source}

Error message

running-left mirror source image no longer exists: {source}

What it means

At finalize time the running-right.png that the left mirror was derived from must still exist, because validate_mirror_hash re-hashes it and re-checks that running-left is a byte-exact horizontal mirror. If the source was removed after the derive step, lineage can no longer be confirmed.

Source

Thrown at skills/hatch-pet/scripts/finalize_pet_run.py:100

    if job_id != "running-left":
        raise SystemExit(f"job {job_id} may not use deterministic mirror provenance")
    if job.get("derived_from") != "running-right":
        raise SystemExit("running-left mirror job must derive from running-right")
    decision = job.get("mirror_decision")
    if not isinstance(decision, dict) or decision.get("approved") is not True:
        raise SystemExit(
            "running-left mirror job is missing an approved mirror_decision; "
            "use derive_running_left_from_running_right.py after visual review"
        )

    expected_source_hash = job.get("source_sha256")
    expected_output_hash = job.get("output_sha256")
    if not isinstance(expected_source_hash, str) or not expected_source_hash:
        raise SystemExit("running-left mirror job is missing source_sha256")
    if not isinstance(expected_output_hash, str) or not expected_output_hash:
        raise SystemExit("running-left mirror job is missing output_sha256")
    if not source.is_file():
        raise SystemExit(f"running-left mirror source image no longer exists: {source}")
    if not output.is_file():
        raise SystemExit(f"running-left mirrored output is missing: {output}")
    if source.name != "running-right.png" or source.parent.name != "decoded":
        raise SystemExit("running-left mirror source must be decoded/running-right.png")
    if output.name != "running-left.png" or output.parent.name != "decoded":
        raise SystemExit("running-left mirror output must be decoded/running-left.png")
    if file_sha256(source) != expected_source_hash:
        raise SystemExit("running-left mirror source hash does not match imagegen-jobs.json")
    if file_sha256(output) != expected_output_hash:
        raise SystemExit(
            "running-left mirrored output hash does not match imagegen-jobs.json; "
            "rerun derive_running_left_from_running_right.py"
        )
    with Image.open(source) as source_image, Image.open(output) as output_image:
        expected = ImageOps.mirror(source_image.convert("RGBA"))
        actual = output_image.convert("RGBA")
        if expected.size != actual.size or expected.tobytes() != actual.tobytes():
            raise SystemExit(

View on GitHub (pinned to 5be4028344)

Solutions

1. Restore decoded/running-right.png by re-running the decode/ingest for running-right (record_imagegen_result.py).
2. Then re-run derive_running_left_from_running_right.py to refresh source_sha256/output_sha256 against the restored file, then finalize.
3. Keep decoded/ intact through the entire derive → finalize pipeline.

import json
from pathlib import Path

run_dir = Path("<run_dir>")
manifest = json.loads((run_dir / "imagegen-jobs.json").read_text())
left = next(j for j in manifest["jobs"] if j.get("id") == "running-left")
if left.get("source_provenance") == "deterministic-mirror":
    source = run_dir / "decoded" / "running-right.png"
    assert source.is_file(), f"mirror source missing: {source}; restore it before finalize"

When it happens

Trigger: decoded/running-right.png was deleted or moved between the derive step and finalize, while the manifest still records it as the mirror source.

Common situations: Cleaning decoded/ between derive and finalize; a partial re-decode that only regenerated some states; running finalize against a pruned copy of the run tree.

Related errors

• running-right decoded strip not found: {source}
• job {job_id} decoded output is missing: {output}
• missing generated strip for {state}: {strip_path}
• job {job_id} source image no longer exists: {source}
• job {job_id} decoded output does not match its recorded sour

AI-assisted analysis of nexu-io/open-design@5be4028344 (2026-08-12). Data as JSON: /api/errors/0547cc782df3bc2d. Report an issue: GitHub.