Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add momomuchu/make-no-mistakes --skill mnm-test-authorgit clone --depth 1 https://github.com/momomuchu/make-no-mistakesWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/momomuchu/make-no-mistakes/mnm-test-author)<a href="https://agentmods.dev/skills/momomuchu/make-no-mistakes/mnm-test-author"><img src="https://agentmods.dev/badge/skills/momomuchu/make-no-mistakes/mnm-test-author/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/momomuchu/make-no-mistakes/mnm-test-author"><img src="https://agentmods.dev/badge/skills/momomuchu/make-no-mistakes/mnm-test-author.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00113 | $0.01298 |
| Opus 5 | $0.00056 | $0.00649 |
| Sonnet 5 | $0.00023 | $0.00260 |
| Haiku 4.5 | $0.00011 | $0.00130 |
Grade A, and why
mnm-test-author scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 11d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.
mnm-test-author
Produces the failing-first tests that make R2's acceptance criteria falsifiable, not just
prose. The independence guarantee here is stronger than the usual "don't peek" prompt
discipline: this role runs before implementation exists, so blindness to the Implementer is a
temporal fact, not a request. Per R32, unlike mnm-planner, this role is a good candidate for a
cheaper/faster model when the runtime offers a choice.
Job
- Read
.mnm/dod.lock.md(frozen) and.mnm/anchors.jsononly — no implementation exists yet. - Optionally call
detect_stack.sh [dir]for the project's test-runner convention and where test files conventionally live. - Write one or more falsifying tests per acceptance criterion, inside DoD-listed test-file globs only.
- Run the new tests via the project's own test command and confirm they currently fail (red) — the negative control: proof the tests can detect the gap at all. A check that cannot fail is not a check (Three Laws, law 3).
- Call
hash_anchors.shto snapshot and freeze exactly the files just written — this closes the tamper window; from this point R3's PreToolUse deny protects them from anyone, including a re-invoked Implementer. - Return
tests.manifest.json. Stop — never attempt to make a test pass; that is the Implementer's job.
When invoked
M+ tier, parallel with mnm-planner — both consume only the frozen DoD, neither depends on the
other. At T/L this role is not spawned separately: its discipline (write the failing check
first) folds into the Implementer's own TDD pass instead. For an H/C tournament, tests are
authored once here, hash-anchored, and become part of the commit every candidate worktree
branches from — identical across all N candidates, never re-authored per candidate.
Delegation-brief contract (11 fields, DD-2)
| Field | Value |
|---|---|
owner |
test-author |
scope |
<dod.lock.md path + hash>, passed as $ARGUMENTS |
action |
Author falsifying tests for every acceptance criterion in dod.lock.md; no implementation code |
context-payload |
Pointer to dod.lock.md + anchors.json only — explicitly nothing about any implementation, because none exists yet |
verify |
Every acceptance criterion has ≥1 mapped test; tests currently fail (red) against the unmodified tree |
done |
tests.manifest.json returned; test files written and hash-anchored |
termination-condition |
Stop once every criterion maps to a failing test — do not attempt to make any test pass |
evidence |
Test files + tests.manifest.json + the red-run output |
write-boundary |
DoD-listed test-file globs only |
conflict-boundary |
None — the Implementer must not touch these paths, per R3's existing PreToolUse deny |
tool/source-restriction |
Write scoped to test globs; Bash restricted to running the new tests to confirm red and to invoking hash_anchors.sh — no other Bash use, no delegation/spawn tools |
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 11d ago First seen · 96 lines · 113 tokens per session scan A 1b80a5397904
mnm-test-author is a skill published in the GitHub repository momomuchu/make-no-mistakes (8 stars, last pushed 2mo ago), licensed MIT. It adds 113 tokens to every session and 1,298 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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