hard-cheese

name	hard-cheese
description	Metacognitive vibecheck gate before code is shared for review — make the author explain the diff's causal logic, graded by a fresh-context judge against the SOLO Taxonomy. Use when the user wants this gate — phrases like "/hard-cheese", "/cheese --hard", "gate this before I push", "vibecheck me", "make sure I understand this diff", "epistemic-debt check". Use standalone before opening a PR, or as the `--hard` flag propagated through the pipeline. Do NOT use for code review (`/age`), test hardening (`/press`), or fix application (`/cure`).
license	MIT
metadata	{"dispatches-agents":true}

/hard-cheese

The gate mitigates epistemic debt — the failure mode where AI-scaffolded code passes review, type-checks, and tests green while the author cannot explain it to a reviewer.

Inputs

/hard-cheese [<slug>] [--socratic-cap N=3] [--passing-score N=3] [--no-judge]

Arguments:

• <slug> — optional. Identifies the artifact at .cheese/hard-cheese/<slug>.md. When omitted, fall back to the git short SHA of HEAD. An explicit slug always wins.
• --socratic-cap N — max retry attempts before the gate marks the artifact FAILED and exits non-zero. Default 3. Vibecheck does not cap; easy-cheese does to avoid infinite loops.
• --passing-score N — minimum SOLO score that counts as PASS. Valid range 1..5; default 3 (Multistructural-or-higher). A previous PASS below the requested threshold is treated as stale and must be re-judged.
• --no-judge — log-only mode. Capture the user's explanation, write the artifact with status: LOGGED, skip the judge sub-agent spawn. Mirrors vibecheck's optional JSONL telemetry mode.

Invocation modes

Mode	How it fires	Where the gate sits
standalone	User runs /hard-cheese <slug> directly before opening a pull request.	Outside the pipeline. No upstream skill required.
propagated	/plate --hard invokes /hard-cheese <slug> after its final writing gate and before publication.	At the verified-artifacts → share-for-review boundary.

--hard propagates through /cheese → /mold → /cook → /press → /age → /cure → /plate. Upstream skills pass the flag; /plate is the only pipeline skill that invokes /hard-cheese.

Portability reference: ../cheese/references/harness-portability.md. It covers helper resolution, sub-agent dispatch, GitHub operations, and handoff transitions; prefer the bundled or repo-local helper first, and treat ${CLAUDE_SKILL_DIR} as optional host-provided fallback. The handoff blocks below are the portable contract; slash commands are host renderings, not the control model.

Flow

1. Resolve scope.

   • diff_base = origin/main, diff_head = <short-sha of HEAD>.
   • If .cheese/specs/<slug>.md exists, load it as the intent reference (optional — diff is the ground truth).
   • Slug fallback when none supplied: the HEAD short SHA.
   • If the working tree has no diff against origin/main, exit 0 with "nothing to gate on" and write no artifact.

2. Freshness check. Check freshness before launching the gate:

   python3 skills/hard-cheese/scripts/hard-cheese.pyz freshness-check \
     --slug <slug> --passing-score <n>
   

   Exit 0 (previously_passed): print "previously passed" and exit 0. Exit 2 (stale: HEAD moved or the last PASS score is below --passing-score) or 3 (new): continue to step 3.

3. Compose the vibecheck prompt (faithful to Sankaranarayanan 2026, generalised to "share for review" so the gate stays implementation-agnostic):

   Before this is shared for review, explain its causal logic in your own words. How does work? Why does it produce the desired behavior? What state, control flow, or invariants does it rely on?

   Render a diff summary alongside the prompt. When invoked by /plate, also render /plate's final artifact inventory and {target, backend, verified} rows so the explanation covers the exact state about to be shared.

4. Capture the user's explanation as free text. No coaching, no example answers — the explanation is the artifact under test.

5. Spawn the judge sub-agent in fresh context (same pattern /ultracook uses for adversarial review). The judge:

   • Reads references/judge-prompt.md as its system prompt.
   • Receives the passing score threshold, the diff summary, the spec excerpt (if any), and the user's explanation as context.
   • Returns a JSON object: {score, level, pass, feedback, socratic_qs}.

   See references/judge-prompt.md for the full system prompt and output shape.

   Skip this step when --no-judge is set: mark the attempt status: LOGGED, write the artifact, exit 0.

6. On judge result:

   • score >= <passing-score> → PASS. score < <passing-score> → FAIL, render Socratic questions, loop to step 4 if attempts < --socratic-cap. Judge error → ERROR attempt, print warning, exit 0 (fail-open — see ## Divergence from the paper).

   Append the attempt row:

   python3 skills/hard-cheese/scripts/hard-cheese.pyz append-attempt \
     --slug <slug> --status <PASS|FAIL|ERROR> --score <n> \
     --feedback "<judge feedback>" --explanation "<user explanation>"
   

7. On cap exhaustion: set the artifact status: FAILED, print the path, exit non-zero. Downstream chains must not proceed.

Artifact

.cheese/hard-cheese/<slug>.md is the audit trail. The directory is gitignored by repo convention (.gitignore already ignores .cheese/), so the trail stays local — matching vibecheck's local-only stance on telemetry.

Each file opens with a YAML frontmatter block that travels with the audit trail:

---
slug: <slug>
attribution: Sankaranarayanan 2026 / vibecheck
rubric: SOLO Taxonomy (1-5), pass threshold = <passing-score>
passing_score: <n>
divergence: fail-open on judge error (vibecheck fails closed)
diff_base: <sha>
diff_head: <short-sha>
status: PASS | FAIL | FAILED | LOGGED
attempts: <n>
---

The attempt log uses a 6-column markdown table (written by append-attempt):

| timestamp | head_sha | status | score | feedback | explanation |
| --- | --- | --- | --- | --- | --- |
| 2026-06-25T10:00:00+00:00 | a1b2c3d | FAIL | 2 | "Unistructural: lists steps but no causal link" | <user explanation verbatim> |
| 2026-06-25T10:05:00+00:00 | a1b2c3d | PASS | 4 | "Relational: explains why invariant holds" | <user explanation verbatim> |

Attempts append; nothing is overwritten within a single invocation. If a re-invocation finds the artifact stale (HEAD moved), new attempt rows are appended below the prior ones — the trail is cumulative.

Sub-agent contract — fresh judge

• Fresh context, every invocation. Same-context judging is biased toward the code it helped write.
• Resolve a no-tool or read-only reviewer through the shared agent resolver at default power and high effort. A general worker qualifies only with prompt-only no-write enforcement and degraded: true.
• references/judge-prompt.md is the system prompt. The judge reads the supplied diff summary, spec excerpt, and explanation, then returns JSON without repository writes.
• JSON output is parsed. If parsing fails, the attempt is logged as ERROR and the gate fails open (see ## Divergence from the paper).

If the host harness has no sub-agent primitive, /hard-cheese is the wrong skill — the gate cannot run without a fresh judge. Recommend /hard-cheese --no-judge for users who still want the explanation captured as telemetry without the grading step.

Attribution

Sankaranarayanan, S. (2026). Mitigating 'Epistemic Debt' in Generative AI-Scaffolded Novice Programming using Metacognitive Scripts. Proceedings of the 13th ACM Conference on Learning at Scale. https://arxiv.org/abs/2602.20206

The implementation reference (intercept-at-acceptance, SOLO rubric, Socratic retry) is the open-source VS Code extension by the paper's author:

https://github.com/sreecharansankaranarayanan/vibecheck

The attribution appears in this SKILL.md, in references/judge-prompt.md, and in every .cheese/hard-cheese/<slug>.md artifact so the citation travels with the audit trail.

Divergence from the paper

Hard-cheese departs from vibecheck in exactly one place, and the divergence is called out explicitly so it stays legible:

Vibecheck fails closed on judge error. If the Judge LLM cannot produce a verdict, the modal blocks code application until the judge recovers or the user retries with a different model.

Hard-cheese fails open on judge error. If the fresh-context judge sub-agent crashes, times out, or returns malformed JSON, the gate writes an ERROR attempt, prints a clear warning, and exits 0 — the user is allowed to proceed.

Rationale: judge invocation is per-PR-attempt and per-retry, and a strict fail-closed policy creates a worse experience under API hiccups than the epistemic-debt cost it averts. New divergences must be added here.

Composition with --auto

--hard and --auto may coexist. The gate punctures auto exactly once inside terminal /plate --hard, after /plate verifies final artifacts and before publication. The user responds, then PASS permits publication, FAILED halts, and ERROR follows the documented fail-open behavior.

Commit-only /plate --hard does not fire because nothing is shared. For a new PR under auto, /plate honors explicit topology, infers an obviously cohesive single, and asks when stacked is recommended or shape is ambiguous. Non-TTY behavior lives in references/composition.md.

Output

When the gate ends, print:

Hard-cheese artifact: .cheese/hard-cheese/<slug>.md
Status: PASS | FAILED | LOGGED | ERROR
Attempts: <n>

Followed by:

• On PASS: Ready to share for review.
• On FAILED: Cap exhausted. Improve understanding of the change before sharing.
• On LOGGED: Telemetry only — judge skipped via --no-judge.
• On ERROR: a one-line warning naming the failure mode and Fail-open divergence active — gate exited 0; you may share for review at your discretion.

Preferred tools and fallbacks

Need	Prefer	Fallback
Diff inspection for the user-facing summary	delta	git diff --unified=3
Reading the spec (when present)	cheez-read	host file read
Spawning the judge	host sub-agent primitive (Agent() or harness equivalent)	none — without sub-agent spawn, run --no-judge mode and tell the user the judge is unavailable
GitHub / PR context (out of scope here)	n/a	n/a

Rules

• The judge sub-agent runs in fresh context. Do not let the same conversation that wrote the code grade the human's understanding of it.
• Do not coach the user before they answer. The explanation is the artifact under test. Socratic questions appear only after a FAIL, and only the questions returned by the judge — no extra hints from the parent.
• Do not paraphrase the user's explanation before passing it to the judge. The judge grades what the user wrote, verbatim.
• Do not skip the freshness check. Re-invoking after HEAD has moved must trigger a fresh attempt sequence — prior comprehension is stale once the code changes.
• Do not silently drop ERROR attempts. The fail-open divergence requires that every judge failure is recorded in the artifact and surfaced to the user as a warning.
• Do not invoke /gh or any specific PR-creation tool. The gate's contract is "before code is shared for review" — implementation-agnostic.
• Apply the shared voice kernel (lives at ../age/references/voice.md): say what the gate result was, flag residual risk as certain | speculating | don't know, do not soften FAILED into "almost passing".

References

• references/judge-prompt.md — SOLO Taxonomy rubric, judge sub-agent system prompt, JSON output shape.
• references/composition.md — the full --hard / --auto matrix and the single puncture point.
• skills/hard-cheese/scripts/hard-cheese.pyz freshness-check — checks whether a previous PASS is still fresh for the current HEAD and passing score (step 2).
• skills/hard-cheese/scripts/hard-cheese.pyz append-attempt — atomically appends an attempt row to the audit trail (step 6).

Agent resolution

Resolve the fresh judge through ../cheese/references/agent-resolution.md.

Work	Preferred types	Permissions/isolation	Minimum power	Effort	Fallback
Grade the explanation	reviewer	no-tool or read-only, fresh-context	default	high	compatible reviewer, then general

The canonical hard-cheese audit carries the shared agent_resolution block.