AIDiveTL;DR e veredito
Quando o Claude Code ignora uma regra, o reflexo é uma linha mais alta no CLAUDE.md. A doc explica por que isso falha: o Claude trata esses arquivos como contexto, não como configuração aplicada, e para bloquear uma ação você usa um hook. s4 O loop da retro vai no sentido contrário: menos linhas e uma checagem que não dá para ignorar.
Na nossa rodada, uma sessão do Claude Code construiu um recurso de notas de crédito numa API de faturamento pequena e entregou um bug de numeração com os próprios testes verdes. Uma retro nessa sessão, informada do que falhou, propôs o que teria evitado o problema. Aprovamos quatro mudanças na mão: um hook de pre-commit, um teste, uma linha de padrões e um comentário na origem. Uma sessão nova, com o mesmo pedido, entregou então os números sem buracos.
O veredito:
- Rode uma retro depois de uma sessão que deu errado, antes de limpá-la, ou sobre o log de uma sessão antiga.
- Não rode no piloto automático. Ela só propõe, e nada muda até você escolher um candidato. s2
- Rastreie cada candidato até um momento do transcript e descarte os que você não consegue rastrear.
- Leve cada sobrevivente ao suporte certo: uma checagem para uma falha mecânica, uma linha de padrões para uma decisão de julgamento, um comentário na origem para uma lacuna de navegação.
- As checagens que você adiciona são código que agora você mantém. A retro não audita as checagens que propôs no mês passado. s2
O pacote abaixo traz o checklist, o script do hook e o teste de numeração da nossa rodada.
Síntese com fontes
O que é a retro. É um skill da coleção do Matt Pocock. Só é invocado pelo usuário (disable-model-invocation: true) e procura candidatos em sete categorias: Navigation, Automated checks, Coding standards, Global AGENTS.md, Tool economy, No-ops e Information access. s1 Seu último passo apenas apresenta os candidatos, por ordem de severidade. s1 Ele passou para o plugin do Claude Code na v1.3.0. s22
Como instalar. A linha de instalação é claude plugin install mattpocock-skills@claude-plugins-official. s25 Uma armadilha: uma issue relatou que o comando da retro sumiu ao instalar pelo marketplace oficial. s24 A entrada do marketplace agora fixa um commit mais novo. s26 Na nossa máquina, o marketplace local ainda estava na fixação antiga, então rodamos primeiro a atualização do marketplace, depois a instalação, e depois conferimos o comando numa sessão nova.
Por que o log, e não o código. O Claude Code guarda os transcripts como JSONL em ~/.claude/projects/<project>/<session-id>.jsonl, e claude --resume <transcript-path> retoma uma sessão a partir desse arquivo. s8 O formato é interno e muda entre versões, então não construa scripts em cima dele. s8 A retenção é de 30 dias e pode ser configurada com cleanupPeriodDays. s8
A retro é barulhenta até você rastreá-la. A doc manda descartar qualquer candidato que você não consiga rastrear até um momento específico. s2 Ela também avisa que o modelo tende a esquecer as dificuldades do meio da sessão e inventa conselhos genéricos para satisfazer as categorias. s2 Uma issue aberta contabiliza 17 rodadas de retro em 12 sessões, 15 delas seguidas por um usuário pedindo ao agente que provasse que os candidatos eram necessários, e pede que zero sobreviventes conte como uma retro completa. s7
Leve cada sobrevivente ao lugar certo. Um repositório sem trava, ou seja, sem hook de pre-commit e sem job de CI rodando seu comando de lint, typecheck ou teste, é por si só um achado. s1 Uma violação mecânica ganha uma checagem determinística, ponto final. s1 Arquivos de direção devem ser usados incredibly sparingly, normalmente só para ponteiros de navegação para outros arquivos. s1 Um desenvolvedor que roda um loop de lições em produção chega à mesma escada: uma regra que escorrega vira um teste, uma regra de lint ou um hook. s6
Mantenha o CLAUDE.md pequeno. A doc mira menos de 200 linhas por arquivo CLAUDE.md, porque arquivos mais longos consomem mais contexto e reduzem a aderência. s4 O teste dela para cada linha: remover isso faria o Claude errar? Se não, corte. s9 O modo de falha do inchaço, uma regra ignorada que ganha uma regra mais alta e um arquivo mais longo, é descrito por um desenvolvedor. s10
Feche o loop. A doc diz para tratar o CLAUDE.md como código: revisá-lo quando algo der errado, podá-lo regularmente e testar as mudanças observando se o comportamento do Claude realmente muda. s9 O /doctor prompt-audit exige o Claude Code v2.1.283 ou mais novo, reporta achados com edições propostas e não muda nada até você pedir. s4 Ele roda pelo skill claude-api embutido, então fica indisponível enquanto esse skill estiver desligado. s4 E uma issue aberta descreve a retro implementando as mudanças aprovadas e depois esquecendo o commit. s23
O que vimos na nossa rodada. A primeira retro abriu com "This session was smooth", porque a sessão nunca soube que tinha falhado. Só depois que relatamos a falha como argumento ela achou a causa, um número pego antes da validação. Os detalhes estão nas medições abaixo.
Código
Cada arquivo é o real da nossa rodada, ou o script que usamos para rodá-la. Edite os caminhos para o seu repositório.
retro-checklist.md é o checklist da página como arquivo: os sete gestos, a pergunta de rastreio palavra por palavra, os quatro suportes, o lembrete do commit e a armadilha do caminho no prompt-audit.
retro-checklist.md
# The retro checklist
Run it after a session that went wrong, before you clear it, or later on the old session's log.
## The seven gestures
1. Install: `claude plugin marketplace update claude-plugins-official`, then `claude plugin install mattpocock-skills@claude-plugins-official --scope project`. Open a NEW session, type a slash, check that the retro command is listed.
2. Run your real task in a plain session. Let it finish. Keep the session open.
3. Run the retro in that session, then run it again with what failed written after it, as its argument. The retro reads the session log, and a session that never learned it failed will call itself smooth.
4. Trace every candidate. Type this, word for word:
> For each candidate, quote the moment of this session's transcript that backs it; drop any candidate you cannot trace to a specific moment.
Zero survivors is a valid retro. Weaker survivors are a judgement call: you decide.
5. Approve one survivor at a time, each into its carrier (below). One change per turn, read the diff after each.
6. Run the prompt audit WITH a path, apply its edits if any, then commit the files yourself. The retro proposes and edits, it does not commit.
7. Re-run the same task in a fresh session and watch what it reads first and whether the failure happens again.
## The four carriers
| What failed | Carrier | Example from our run |
| --- | --- | --- |
| A mechanical failure | A deterministic check: a pre-commit hook, a test, a lint rule, a CI job | `pre-commit.sh` (typecheck, then tests) and `numbering.test.ts` |
| A judgement call | One line in `CODING_STANDARDS.md`, read by the reviewer | `CODING_STANDARDS.md` |
| A navigation gap | A comment at the source, or one CLAUDE.md pointer if a comment cannot do it | A doc comment above `nextId` |
| Nothing the above can hold | Do not write a rule | Both retros declined a CLAUDE.md line |
## Traps
- Commit reminder: the retro can implement what you approve and then leave the files uncommitted. Stage the approved files and commit them yourself.
- A new hook checks the working tree, not the commit. If the tree still holds the bug, the hook refuses the commit. Fix the code first, then commit.
- A cherry-pick does not run the pre-commit hook.
- Prompt-audit path trap: `/doctor prompt-audit` with no path audited the user-level files under `~/.claude`, not the repo, and said nothing about the new files. Give it the path: `/doctor prompt-audit CODING_STANDARDS.md`.
- The retro has no dry-run mode. Try a proposed check against the repo before you let it block merges.
- Do not wire the retro to a session-end hook. Keep a human on the approval.
- Keep the transcript format out of your scripts: it is internal and changes between versions.
pre-commit.sh é o hook que aprovamos. Ele roda o typecheck e depois os testes, e bloqueia o commit se qualquer um falhar. Salve como .githooks/pre-commit, torne-o executável e rode git config core.hooksPath .githooks.
pre-commit.sh
#!/bin/sh
set -e
pnpm typecheck
pnpm test
numbering.test.ts é o teste vitest que aprovamos. Ele trava uma regra: uma requisição de nota de crédito rejeitada não queima nenhum número.
numbering.test.ts
import { describe, expect, it } from "vitest";
import { seedCustomer, seedOpenInvoice, testApp } from "./helpers";
describe("credit note numbering", () => {
it("does not burn a number on a rejected request", async () => {
const app = testApp();
const customerId = await seedCustomer(app);
const id = await seedOpenInvoice(app, { customerId, unitPrice: 10_000 });
await app.handle("POST", `/invoices/${id}/pay`);
const url = `/invoices/${id}/credit-notes`;
const first = await app.handle("POST", url, { amount: 4_000 });
expect(first.body).toMatchObject({ number: "CN-0001" });
const rejected = await app.handle("POST", url, { amount: 6_001 });
expect(rejected.status).not.toBe(201);
const next = await app.handle("POST", url, { amount: 6_000 });
expect(next.status).toBe(201);
expect(next.body).toMatchObject({ number: "CN-0002" });
});
});
CODING_STANDARDS.md é a linha de padrões que aprovamos, o arquivo que um revisor lê.
CODING_STANDARDS.md
# Coding standards
- Take a sequence number (`nextId`) only once every validation has passed, so a rejected request leaves the sequence gapless.
retro-output.md é o texto completo das duas passadas da retro e das duas respostas de rastreio da nossa sessão.
retro-output.md
# Retro output, session A (cb5884fb-bd6f-4684-8866-d0adc12ac26e)
## 1. `/retro` (resumed headless, 2026-10-23 10:39:44, $0.0658, 17.5 s, 5 turns)
Prompt typed: `/retro` -> transcript records `<command-name>/mattpocock-skills:retro</command-name>`. Tool calls: Skill(mattpocock-skills:writing-for-agents), Bash(ls -a; ls .github; ls .git/hooks | grep -v sample; cat tsconfig.json), Bash(find .claude -type f; cat .claude/settings*.json).
Verbatim:
> This session was smooth. The pass came out clean on the first typecheck and test run, and I found no `AGENTS.md`/`CLAUDE.md` or `CODING_STANDARDS.md` to prune. The candidates below are in order of severity.
>
> **1. No guardrail runs the checks (automated checks)**
> - `package.json` already has `test` and `typecheck`, but nothing runs them: there's no `.github/` workflow and no pre-commit hook.
> - This session only stayed green because I ran both by hand. An agent, or a person, can commit a type error or a failing test.
> - **Fix:** add a CI job running `pnpm typecheck && pnpm test`, plus a pre-commit hook running the same. Neither needs prose.
>
> **2. The migration rule is the one convention that could be missed (automated checks)**
> - The README says "any change to the stored shape bumps `schemaVersion` and adds a migration".
> - I found it only because I read `README.md` while working out the design. If I'd skipped it, nothing would have failed. Adding a field to `StoreData` without a migration still typechecks.
> - **Fix:** a test that fails when someone changes the stored shape without bumping the version. For example, snapshot the output of `migrate({})` and assert the snapshot's `schemaVersion` equals `CURRENT_SCHEMA_VERSION`. This is a deterministic check, so it should replace the README sentence rather than add to it.
>
> **3. Adding a counter or store collection touches five places (navigation)**
> - Adding credit notes meant editing `types.ts`, `json-store.ts` (the `empty()` function), `migrations.ts` (the migration, plus the fallback defaults at the bottom of `migrate`), `context.ts`, and a new repo file.
> - The `{ customer: 0, invoice: 0, invoiceNumber: 0 }` literal is duplicated in `json-store.ts` and `migrations.ts`. I had to find both with `grep`.
> - **Fix:** have `migrate` build its defaults from one shared `emptyData()`. That removes a hidden dependency rather than documenting it. A pointer in a steering file would cost context on every turn and go stale, so I wouldn't write one.
>
> **4. Nothing for the reviewer to enforce (coding standards)**
> - There's no `CODING_STANDARDS.md`. The README's conventions are mostly mechanical: integer cents, domain functions that don't mutate their input, and which error type maps to which status.
> - A reviewer agent would have no judgement-call rules to apply. I wouldn't add any until a real review miss shows one is needed.
>
> **5. Tool economy and information access: nothing to change**
> - My one failed Bash call (a rejected heredoc) cost a retry, but that was my command and not the tooling.
> - I had everything I needed, since the tests call `createApp().handle` directly with no server or logs to tee.
>
> I'd start with 1 and 2. They're small, mechanical, and would catch the likeliest future mistake. Want me to add the CI workflow, the pre-commit hook and the schema-version test?
## 2. Trace step (same session, 10:40:33, $0.0322, 17.1 s, 1 turn)
Prompt: "For each candidate, quote the moment of this session's transcript that backs it; drop any candidate you cannot trace to a specific moment."
Verbatim:
> Two of the five candidates have no support in the transcript, and I got a detail wrong in a third. Here is each one against what actually happened.
>
> **1. No guardrail: kept**
> - The moment is my `ls -a; ls .github 2>/dev/null; ls .git/hooks | grep -v sample` command. The listing shows `.claude .git .gitignore data node_modules package.json … vitest.config.ts`. There is no `.github`, and the hooks `grep` printed nothing.
> - It isn't a mistake I made, since my own `pnpm typecheck` and `pnpm test` run came back clean. It's a repo-state finding: the checks exist as scripts and nothing runs them.
>
> **2. Migration rule has no check: dropped**
> - I can't point to a moment where I missed or nearly missed a migration. I read `migrations.ts` in my first big `cat`, before I'd seen the README. I would have found the migration step either way, so my claim that I found it only through the README was wrong.
> - "Nothing would have failed if I'd skipped it" is a hypothetical, not something that happened.
>
> **3. Five places to touch for a new collection: kept, but weaker than I said**
> - The moment is my batch of edits to `types.ts`, `json-store.ts`, `migrations.ts` and `context.ts`. Two of them changed the same literal, `{ customer: 0, invoice: 0, invoiceNumber: 0 }`, which now reads `…, creditNote: 0`. It appears in both `json-store.ts` and the fallback in `migrate`.
> - I said I "had to find both with `grep`". That's wrong. I never ran one, since the `grep` was in the command that was rejected. I already knew both locations from reading the files, and the edits went through without friction.
> - The duplicated literal is real but caused no trouble. I'd rate it low severity.
>
> **4. No `CODING_STANDARDS.md`: dropped**
> - The only moment is the `git ls-files` output showing the file doesn't exist. No review step happened in this session and no reviewer missed anything.
> - "I wouldn't add any until a real review miss shows one is needed" was my own opinion, not something the session showed.
>
> **5. Tool economy: dropped as a finding**
> - The moment is my first Bash call being rejected with `Contains brace with quote character (expansion obfuscation)`. It cost one retry, and I switched to Write and Edit.
> - It was a one-off, and I can't tell from the transcript whether the harness or my heredoc-in-Python approach was at fault. I don't think it justifies a change.
>
> That leaves candidate 1 as the only solid finding and candidate 3 as a minor one. For 1, I can add a CI workflow and a pre-commit hook that both run `pnpm typecheck && pnpm test`.
## 3. Second `/retro`, with the defect reported by the developer (same session, 10:41:10, $0.0491, 23.1 s, 1 turn, no tool call; it skipped the writing-for-agents reload)
Prompt: `/retro Finance tested this build after the session: they sent a credit note that was too big (rejected, fine), and the next valid credit note came out CN-0004 where CN-0002 was due. Rejected requests burn credit-note numbers. Don't fix the code; run the retro on this session with that failure in mind.`
Verbatim:
> I'm skipping the style-guide reload because it's already in this session. The cause is in my own code, and I traced each finding to a specific moment.
>
> **What happened**
> - In `issueCreditNote` (`src/http/handlers/invoices.ts`) I call `ctx.store.nextId("creditNote")` first and `createCreditNote(...)` second. `nextId` persists the counter immediately, and `createCreditNote` is what throws the 409 for an over-limit amount. So a rejected request still burns a number.
> - I copied the order from the existing `/issue` handler, which I had read. It does `const n = ctx.store.nextId("invoiceNumber"); const issued = issue(current, ...)`, and `issue()` throws if the invoice isn't a draft. So issuing a non-draft invoice probably burns an `INV-` number the same way. I haven't run that, only read it.
>
> **1. A test that would have caught it: I wrote the scenario and skipped the assertion (automated checks)**
> - The moment is the test I wrote: "rejects bad amounts (400) and amounts above what is left (409)".
> ```
> await app.handle("POST", ..., { amount: 8_000 });
> expect((await app.handle("POST", ..., { amount: 1_001 })).status).toBe(409);
> expect((await app.handle("POST", ..., { amount: 1_000 })).status).toBe(201);
> ```
> That is exactly Finance's sequence: accept, reject, accept. I only checked status codes, never the number on the last note, which comes out as `CN-0003`.
> - The "numbers credit notes sequentially" test only covers two successful requests in a row.
> - **Fix:** add a test that each numbered sequence (`INV-`, `CN-`) stays gapless after rejected requests. Run it over both sequences, which also exposes the `/issue` case.
> - **Rule:** when a test reaches a failure path, assert the state afterwards, not just the status code.
>
> **2. `nextId` looks pure but isn't (navigation)**
> - In `json-store.ts`, `nextId(kind)` runs `this.update(...)`, so every call writes to the counter and persists it. The `Store` type in `json-store.ts` has only the signature `nextId(kind: keyof Counters): number;`, with no comment about the side effect.
> - Nothing at the call site tells you to allocate only after validation. This is a gotcha no config reveals, so a short doc comment on `nextId` is worth its cost. Something like: "Consumes the number even if the caller then fails; call it only after validation."
> - Keep it as a comment on `nextId`, not a steering-file line. It matters only to someone calling `nextId`, and it can't go stale there.
>
> **3. The gapless-numbering convention isn't written down (coding standards)**
> - The README's "Conventions" list has cents, immutability, error-to-status mapping, and migrations. It says nothing about invoice or credit-note numbers being gapless, though the request ("numbered `CN-0001`, `CN-0002`...") implies it.
> - This is partly a judgement call: reviewers need to know that numbers are allocated after validation. One README line would do. Finding 1's test is the deterministic check; the README line explains why the test exists.
>
> **4. Missing CI, from the first retro: still real, but it wouldn't have helped here**
> - My own typecheck and tests passed, so a CI job would also have passed. I'm keeping it as a separate, unrelated finding, not as a cause of this failure.
>
> **5. My summary stated the rules but didn't test them**
> - I told you "Rules I chose" and flagged the two-update void risk, but never exercised a rejection followed by a success. The summary read as complete when that path was untested. This is a process gap, and finding 1 is the fix.
>
> I'd start with 1 and 2. I haven't touched the code, as you asked.
## 4. Trace step on the second retro (same session, 10:41:43, $0.0498, 33.4 s, 1 turn)
Prompt: same trace prompt as section 2.
Verbatim:
> I traced each candidate again. Two survive on firm evidence, two survive but with a gap I should state, and one is dropped.
>
> **1. Test asserts status but not the number: kept, firm**
> - The moment is the test I wrote in `test/credit-notes.test.ts`:
> ```
> await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 8_000 });
> expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 1_001 })).status).toBe(409);
> expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 1_000 })).status).toBe(201);
> ```
> That is accept, reject, accept, with only status codes checked. By my reading of the handler, the last note comes out as `CN-0003`. I derived that and haven't run it.
> - The adjacent test, "numbers credit notes sequentially…", covers two successes in a row and never a rejection.
> - The cause, which I only read and haven't run, is this in the handler I wrote:
> ```
> const id = ctx.store.nextId("creditNote");
> const note = createCreditNote(invoice, existing, amount, …
> ```
> That order matches the existing issue handler, which I read:
> ```
> const n = ctx.store.nextId("invoiceNumber");
> const issued = issue(current, `INV-…`, ctx.now());
> ```
> and `issue()` throws `ConflictError` for non-drafts. So the `INV-` sequence very likely has the same leak. I haven't run that either.
>
> **2. `nextId` has no warning about its side effect: kept, firm on the facts**
> - The moment is the `Store` type I read in `json-store.ts`. `update` has a comment ("Apply a change and persist it (when file-backed)."), while `nextId(kind: keyof Counters): number;` has none. Its implementation calls `this.update(...)`, so it persists immediately.
> - The `/issue` call site I copied has no comment either.
> - I can't show that a comment would have changed what I did, because I never weighed the ordering at all. I copied it. The comment is a bet on the next caller, not a proven fix.
>
> **3. Gapless numbering isn't written in the README: kept, weaker**
> - The moment is the `README.md` output I read before writing the handler. Its Conventions list covers cents, no mutation, error-to-status mapping and `schemaVersion`. It has no line about numbers.
> - So the agent doing the implementation, meaning me, read the conventions and found nothing on this.
> - I overstated one thing last turn. Your request said "numbered `CN-0001`, `CN-0002`...", and I said that implies gapless numbers. That was my inference, not your words. Finance has now confirmed it as a requirement, but nothing in the original request stated it.
>
> **4. No CI or pre-commit hook: kept, unrelated to this failure**
> - The moment is my `ls -a; ls .github 2>/dev/null; ls .git/hooks | grep -v sample` output, which showed no `.github` and no hooks.
> - It wouldn't have caught this. My own run ended `Tests 42 passed (42)`, and CI would have passed too.
>
> **5. "My summary stated rules without testing them": dropped**
> - I can quote the summary ("Rules I chose", plus the line about the void being two separate store updates). But it describes my behaviour, not a change to the environment, and finding 1 already covers the underlying gap. Keeping it would count one moment twice.
>
> The order of importance is 1, 2, then 3. Finding 4 stays on the list but belongs to a separate piece of work. I still haven't changed any code.
doctor-prompt-audit.md é o prompt audit rodado sem caminho e depois com caminho. Mostra a armadilha do caminho.
doctor-prompt-audit.md
# `/doctor prompt-audit` (no path) on the ledgerly copy, session 26612b59-9edd-493b-a397-fb54300fa037
# Prompt audit: Claude Code configuration for ledgerly
**Assumptions**
- **Target model:** Claude Sonnet 5.5, the model running this session. A skill that writes prompts for other models (`prompt-master`) is audited for its Claude-facing text only.
- **Scope:** only the Claude Code configuration that loads into this project, as you specified. I proposed no edits to plugin files.
- **Settings and secrets:** I did not read `.claude/settings.json`, `.mcp.json` or `~/.claude.json`.
- **Edits are not applied.** Every edit below touches `~/.claude/`, so it **affects all projects**.
- **Dependency not verified:** I could not verify that `~/.claude` is under git, so I used no `git blame`. No hunk below relies on history.
**Inventory**
- **Project files:** none. The project root has no `CLAUDE.md`, `CLAUDE.local.md`, `AGENTS.md` or `.claude/` instruction files. The ancestors `/path/to/work` and `/private/tmp` have none either.
- **Managed policy:** no managed-policy `CLAUDE.md` exists.
- **User level:**
- `~/.claude/CLAUDE.md`, which imports `~/.claude/RTK.md`.
- `~/.claude/rules/context7.md`.
- 27 skills under `~/.claude/skills/*/SKILL.md`.
- There are no `commands/`, `agents/` or `output-styles/` folders.
- **Plugins:** `caveman`, `marketing`, `cowork-plugin-management` and `gleam-reels` are installed. I did not audit them in depth, and they have no findings or edits.
- **Coverage gap:** I read `CLAUDE.md`, `RTK.md`, the rule, `context7-mcp`, most of `prompt-master`, the relevant parts of `graphify`, and the top of `agent-reach`. I covered the other skills (Cloudflare, HyperFrames, browser, media) with signal greps and frontmatter only. I did not read their `references/` subfiles.
- **Possible mismatch:** this session's skill list shows none of the `~/.claude/skills/*` entries. These files may not be loading in this project, so the skill findings may not affect it.
## Findings of the first run
The audit without a path found no project instruction files and went on to audit the user-level files under the home folder instead: six proposed edits and four flags, all about files outside this repository, none applied. That part is left out of this copy because it concerns one developer's personal configuration, not the project.
# Second run: `/doctor prompt-audit CODING_STANDARDS.md` (session 9b5f0cd5-1701-498e-8d05-0355c7f1ece6)
## Prompt audit: `CODING_STANDARDS.md`
**Assumptions**
- **Scope:** only `CODING_STANDARDS.md`, which the request names. The inventory found no `CLAUDE.md`, `AGENTS.md`, rule files, skills, commands or subagents in the repo. `.claude/settings.json` exists but I did not read it, per the audit rules.
- **Target model:** Claude Sonnet 5.5, the model running this audit. The file is read by the coding agent, not by application code.
- **Group 4 (request config and architecture):** not applicable. The file is an agent instruction file and has no request-building code.
**Result: the file is clean.** It has one line, so there is nothing to change and the proposed diff is empty.
**Inventory:** `CODING_STANDARDS.md` has one rule at line 3: "Take a sequence number (`nextId`) only once every validation has passed, so a rejected request leaves the sequence gapless."
**Checks**
| Group | Findings |
|---|---|
| 1 Dated prompt text | 0. The rule has no emphasis, hedging, scaffold or step list. It states a reason, so it is context the model can't know, not a prohibition without provenance. |
| 2 Brittle config files | 0. `git blame` puts the line in `adaa593`, the retro commit that followed the credit-note session. It encodes a failure that actually happened, not a one-off stumble. |
| 3 Tool descriptions | Not applicable. |
| 4 Request config and architecture | Not applicable. |
Group 2 also covers stale facts. `nextId` is still defined (`src/store/json-store.ts:11,52`) and the sequence kinds it names still exist. No other instruction file ranks on the same point, so there is no conflict.
**One thing outside the audit:** the rule is violated in the code. `src/http/handlers/invoices.ts:44` calls `ctx.store.nextId("invoiceNumber")` before `issue()` runs. `issue()` throws `ConflictError` for any non-draft invoice (`src/domain/invoice.ts:42-44`). Issuing an already-issued, paid or void invoice therefore consumes an invoice number and leaves a gap. The fix is to validate first, or to pass an allocator into `issue()` the way `createCreditNote` takes `allocate`. I didn't check `customers.ts:8` or `credit-note.ts`.
This is a code bug, not a prompt problem, and the rule is working as intended. Keep it, and consider an enforcing test: `test/numbering.test.ts` may only cover credit notes. I haven't edited anything.
doctor-prompt-audit.md on GitHub
run-session.sh roda um turno headless do Claude Code num setup isolado, só do projeto, com uma lista de permissões. Edite a linha de env para a sua.
run-session.sh
#!/usr/bin/env bash
# Usage: run-session.sh <workdir> <out.json> <prompt> [resume-session-id]
# One headless Claude Code turn with an isolated project-only setup and an allow-list.
set -uo pipefail
W="$1"; OUT="$2"; PROMPT="$3"; SID="${4:-}"
source ./env.sh # your own env: unset CLAUDE* variables, optionally CLAUDE_CODE_DISABLE_AUTO_MEMORY=1
ALLOWED="Read,Edit,Write,MultiEdit,Glob,Grep,Skill,TodoWrite,Task,Agent,Bash(node:*),Bash(npm:*),Bash(pnpm:*),Bash(npx vitest:*),Bash(npx tsc:*),Bash(tsc:*),Bash(git status:*),Bash(git diff:*),Bash(git log:*),Bash(git add:*),Bash(git commit:*),Bash(git checkout -b:*),Bash(ls:*),Bash(cat:*),Bash(mkdir:*),Bash(head:*),Bash(tail:*),Bash(grep:*),Bash(wc:*),Bash(gh:*)"
DIS="AskUserQuestion,EnterPlanMode,ExitPlanMode,EnterWorktree,ExitWorktree,WebFetch,WebSearch"
ARGS=(-p "$PROMPT")
[ -n "$SID" ] && ARGS+=(--resume "$SID")
cd "$W" || exit 1
T0=$(date +%s)
claude "${ARGS[@]}" --model claude-sonnet-5-5 --permission-mode acceptEdits --output-format json \
--allowedTools "$ALLOWED" --disallowedTools "$DIS" --setting-sources project --strict-mcp-config \
> "$OUT" 2> "$OUT.stderr" < /dev/null
RC=$?
echo "rc=$RC wall=$(( $(date +%s) - T0 ))s" | tee "$OUT.wall"
python3 -c "import json,sys;d=json.load(open(sys.argv[1]));print({k:d.get(k) for k in ('session_id','total_cost_usd','duration_ms','num_turns','is_error','subtype')})" "$OUT"
oracle.sh roda o teste escondido do financeiro, cinco requisitos checados de fora da sessão, contra uma cópia de trabalho. Aponte para os seus próprios testes escondidos.
oracle.sh
#!/usr/bin/env bash
# Usage: oracle.sh <workdir> <out.json> -- the hidden finance test for the credit-note task, run from OUTSIDE the work copy.
H=/path/to/hidden-tests
W="$1"; OUT="$2"
cd "$H" && env -u CLAUDECODE WORK="$W" BASE="$(git -C "$W" rev-list --max-parents=0 HEAD | head -1)" TASK=F2 \
"$H/node_modules/.bin/vitest" run --reporter=json --outputFile="$OUT" > "$OUT.log" 2>&1
python3 - "$OUT" <<'PY'
import json,sys
j=json.load(open(sys.argv[1]))
for tr in j["testResults"]:
for a in tr["assertionResults"]:
print(a["status"].upper(), a["title"]);
if a["status"]!="passed": print(" ", " ".join(a.get("failureMessages") or [])[:500].replace("\n"," | "))
PY
sessionA-F2.diff é o código da sessão que entregou o bug, com a correção.
sessionA-F2.diff
diff --git a/README.md b/README.md
index 890f13c..ae1e4f9 100644
--- a/README.md
+++ b/README.md
@@ -27,4 +27,8 @@ pnpm typecheck # tsc --noEmit
## Invoice lifecycle
-`draft` → (`issue`) → `open` → (`pay`) → `paid`; `draft`/`open` → (`void`) → `void`.
+`draft` → (`issue`) → `open` → (`pay`) → `paid`; `draft`/`open`/`paid` → (`void`) → `void`.
+
+Credit notes (`POST`/`GET /invoices/:id/credit-notes`, numbered `CN-0001`, ...) can be issued against
+`open` or `paid` invoices, up to the invoice total minus earlier credit notes. Open invoices' credits
+reduce the outstanding report. Voiding a paid invoice issues a credit note for whatever is left.
diff --git a/src/domain/credit-note.ts b/src/domain/credit-note.ts
new file mode 100644
index 0000000..9a48b40
--- /dev/null
+++ b/src/domain/credit-note.ts
@@ -0,0 +1,43 @@
+import { ConflictError, ValidationError } from "./errors";
+import { computeTotals, type Invoice } from "./invoice";
+import { assertCents, type Cents, type Currency, sum } from "./money";
+
+export type CreditNote = {
+ id: string;
+ /** CN-0001, ... */
+ number: string;
+ invoiceId: string;
+ currency: Currency;
+ /** cents, always positive */
+ amount: Cents;
+ createdAt: string;
+};
+
+export function parseCreditNoteAmount(body: unknown): Cents {
+ if (typeof body !== "object" || body === null) {
+ throw new ValidationError("body must be an object");
+ }
+ return assertCents((body as Record<string, unknown>).amount, "amount", { min: 1 });
+}
+
+/** What is still creditable on an invoice: its total minus the credit notes already issued. */
+export function remainingCredit(invoice: Invoice, notes: CreditNote[]): Cents {
+ return computeTotals(invoice).total - sum(notes.map((n) => n.amount));
+}
+
+export function createCreditNote(
+ invoice: Invoice,
+ existing: CreditNote[],
+ amount: Cents,
+ ids: { id: string; number: string },
+ now: Date,
+): CreditNote {
+ if (invoice.status !== "open" && invoice.status !== "paid") {
+ throw new ConflictError(`invoice ${invoice.id} is ${invoice.status}, only open or paid invoices can be credited`);
+ }
+ const remaining = remainingCredit(invoice, existing);
+ if (amount > remaining) {
+ throw new ConflictError(`credit note of ${amount} exceeds the ${remaining} still creditable on invoice ${invoice.id}`);
+ }
+ return { ...ids, invoiceId: invoice.id, currency: invoice.currency, amount, createdAt: now.toISOString() };
+}
diff --git a/src/domain/invoice.ts b/src/domain/invoice.ts
index 5b69fc9..1a3967b 100644
--- a/src/domain/invoice.ts
+++ b/src/domain/invoice.ts
@@ -52,8 +52,9 @@ export function markPaid(invoice: Invoice, now: Date): Invoice {
return { ...invoice, status: "paid", paidAt: now.toISOString() };
}
+/** Paid invoices can be voided too, but the caller must credit what is left on them first. */
export function voidInvoice(invoice: Invoice, now: Date): Invoice {
- if (invoice.status === "paid" || invoice.status === "void") {
+ if (invoice.status === "void") {
throw new ConflictError(`invoice ${invoice.id} is ${invoice.status} and cannot be voided`);
}
return { ...invoice, status: "void", voidedAt: now.toISOString() };
diff --git a/src/http/context.ts b/src/http/context.ts
index c0a89d3..38d7ffa 100644
--- a/src/http/context.ts
+++ b/src/http/context.ts
@@ -1,5 +1,6 @@
import type { Store } from "../store/json-store";
import { customerRepo } from "../store/customer-repo";
+import { creditNoteRepo } from "../store/credit-note-repo";
import { invoiceRepo } from "../store/invoice-repo";
export type AppContext = {
@@ -7,8 +8,9 @@ export type AppContext = {
now: () => Date;
customers: ReturnType<typeof customerRepo>;
invoices: ReturnType<typeof invoiceRepo>;
+ creditNotes: ReturnType<typeof creditNoteRepo>;
};
export function createContext(store: Store, now: () => Date = () => new Date()): AppContext {
- return { store, now, customers: customerRepo(store), invoices: invoiceRepo(store) };
+ return { store, now, customers: customerRepo(store), invoices: invoiceRepo(store), creditNotes: creditNoteRepo(store) };
}
diff --git a/src/http/handlers/invoices.ts b/src/http/handlers/invoices.ts
index 09959e1..17b3910 100644
--- a/src/http/handlers/invoices.ts
+++ b/src/http/handlers/invoices.ts
@@ -1,3 +1,4 @@
+import { type CreditNote, createCreditNote, parseCreditNoteAmount, remainingCredit } from "../../domain/credit-note";
import { ValidationError } from "../../domain/errors";
import { type Invoice, type InvoiceStatus, issue, markPaid, voidInvoice } from "../../domain/invoice";
import { parseNewInvoice } from "../../domain/validation";
@@ -51,8 +52,33 @@ export function invoiceRoutes(router: Router, ctx: AppContext): void {
return { status: 200, body: invoiceView(ctx.invoices.save(paid)) };
});
+ /** Voiding a paid invoice credits whatever is left on it, so the books stay balanced. */
router.on("POST", "/invoices/:id/void", ({ params }) => {
- const voided = voidInvoice(ctx.invoices.get(params.id), ctx.now());
+ const current = ctx.invoices.get(params.id);
+ const now = ctx.now();
+ const voided = voidInvoice(current, now);
+ if (current.status === "paid") {
+ const left = remainingCredit(current, ctx.creditNotes.listForInvoice(current.id));
+ if (left > 0) issueCreditNote(current, left);
+ }
return { status: 200, body: invoiceView(ctx.invoices.save(voided)) };
});
+
+ router.on("POST", "/invoices/:id/credit-notes", ({ params, body }) => {
+ const invoice = ctx.invoices.get(params.id);
+ const amount = parseCreditNoteAmount(body);
+ return { status: 201, body: issueCreditNote(invoice, amount) };
+ });
+
+ router.on("GET", "/invoices/:id/credit-notes", ({ params }) => {
+ const invoice = ctx.invoices.get(params.id);
+ return { status: 200, body: ctx.creditNotes.listForInvoice(invoice.id) };
+ });
+
+ function issueCreditNote(invoice: Invoice, amount: number): CreditNote {
+ const existing = ctx.creditNotes.listForInvoice(invoice.id);
+ const id = ctx.store.nextId("creditNote");
+ const note = createCreditNote(invoice, existing, amount, { id: `cn_${id}`, number: `CN-${String(id).padStart(4, "0")}` }, ctx.now());
+ return ctx.creditNotes.insert(note);
+ }
}
diff --git a/src/http/handlers/reports.ts b/src/http/handlers/reports.ts
index 19262c9..c84089a 100644
--- a/src/http/handlers/reports.ts
+++ b/src/http/handlers/reports.ts
@@ -1,4 +1,5 @@
-import { computeTotals, isOverdue } from "../../domain/invoice";
+import { remainingCredit } from "../../domain/credit-note";
+import { isOverdue } from "../../domain/invoice";
import type { Currency } from "../../domain/money";
import type { AppContext } from "../context";
import type { Router } from "../router";
@@ -11,8 +12,8 @@ export function reportRoutes(router: Router, ctx: AppContext): void {
let count = 0;
let overdue = 0;
for (const invoice of ctx.invoices.list({ status: "open" })) {
- const { total } = computeTotals(invoice);
- totals[invoice.currency] = (totals[invoice.currency] ?? 0) + total;
+ const owed = remainingCredit(invoice, ctx.creditNotes.listForInvoice(invoice.id));
+ totals[invoice.currency] = (totals[invoice.currency] ?? 0) + owed;
count += 1;
if (isOverdue(invoice, now)) overdue += 1;
}
diff --git a/src/store/credit-note-repo.ts b/src/store/credit-note-repo.ts
new file mode 100644
index 0000000..c922142
--- /dev/null
+++ b/src/store/credit-note-repo.ts
@@ -0,0 +1,14 @@
+import type { CreditNote } from "../domain/credit-note";
+import type { Store } from "./json-store";
+
+export function creditNoteRepo(store: Store) {
+ return {
+ listForInvoice(invoiceId: string): CreditNote[] {
+ return store.read().creditNotes.filter((n) => n.invoiceId === invoiceId);
+ },
+ insert(note: CreditNote): CreditNote {
+ store.update((d) => ({ ...d, creditNotes: [...d.creditNotes, note] }));
+ return note;
+ },
+ };
+}
diff --git a/src/store/json-store.ts b/src/store/json-store.ts
index b404c51..99205b7 100644
--- a/src/store/json-store.ts
+++ b/src/store/json-store.ts
@@ -13,9 +13,10 @@ export type Store = {
function empty(): StoreData {
return {
schemaVersion: CURRENT_SCHEMA_VERSION,
- counters: { customer: 0, invoice: 0, invoiceNumber: 0 },
+ counters: { customer: 0, invoice: 0, invoiceNumber: 0, creditNote: 0 },
customers: [],
invoices: [],
+ creditNotes: [],
};
}
diff --git a/src/store/migrations.ts b/src/store/migrations.ts
index c8b73a9..91d4f99 100644
--- a/src/store/migrations.ts
+++ b/src/store/migrations.ts
@@ -1,6 +1,6 @@
import type { StoreData } from "./types";
-export const CURRENT_SCHEMA_VERSION = 1;
+export const CURRENT_SCHEMA_VERSION = 2;
type RawData = Record<string, unknown> & { schemaVersion?: number };
type Migration = (data: RawData) => RawData;
@@ -21,9 +21,18 @@ const v0ToV1: Migration = (data) => {
};
};
+/** v1 -> v2: credit notes (a `creditNotes` list and a `creditNote` counter). */
+const v1ToV2: Migration = (data) => ({
+ ...data,
+ schemaVersion: 2,
+ counters: { creditNote: 0, ...(data.counters as Record<string, number> | undefined) },
+ creditNotes: (data.creditNotes as unknown[] | undefined) ?? [],
+});
+
/** migrations[n] upgrades a file from version n to n + 1. */
const migrations: Record<number, Migration> = {
0: v0ToV1,
+ 1: v1ToV2,
};
export function migrate(raw: unknown): StoreData {
@@ -43,8 +52,9 @@ export function migrate(raw: unknown): StoreData {
}
return {
schemaVersion: CURRENT_SCHEMA_VERSION,
- counters: (data.counters as StoreData["counters"]) ?? { customer: 0, invoice: 0, invoiceNumber: 0 },
+ counters: (data.counters as StoreData["counters"]) ?? { customer: 0, invoice: 0, invoiceNumber: 0, creditNote: 0 },
customers: (data.customers as StoreData["customers"]) ?? [],
invoices: (data.invoices as StoreData["invoices"]) ?? [],
+ creditNotes: (data.creditNotes as StoreData["creditNotes"]) ?? [],
};
}
diff --git a/src/store/types.ts b/src/store/types.ts
index 222b191..a9d7277 100644
--- a/src/store/types.ts
+++ b/src/store/types.ts
@@ -1,7 +1,8 @@
+import type { CreditNote } from "../domain/credit-note";
import type { Customer } from "../domain/customer";
import type { Invoice } from "../domain/invoice";
-export type Counters = { customer: number; invoice: number; invoiceNumber: number };
+export type Counters = { customer: number; invoice: number; invoiceNumber: number; creditNote: number };
/** The shape of the JSON file at CURRENT_SCHEMA_VERSION. */
export type StoreData = {
@@ -9,4 +10,5 @@ export type StoreData = {
counters: Counters;
customers: Customer[];
invoices: Invoice[];
+ creditNotes: CreditNote[];
};
diff --git a/test/credit-notes.test.ts b/test/credit-notes.test.ts
new file mode 100644
index 0000000..f841a3c
--- /dev/null
+++ b/test/credit-notes.test.ts
@@ -0,0 +1,94 @@
+import { describe, expect, it } from "vitest";
+import { openStore } from "../src/store/json-store";
+import { migrate } from "../src/store/migrations";
+import { seedCustomer, seedOpenInvoice, testApp } from "./helpers";
+
+async function setup(opts: { unitPrice?: number; discount?: number } = {}) {
+ const app = testApp();
+ const customerId = await seedCustomer(app);
+ const id = await seedOpenInvoice(app, { customerId, unitPrice: opts.unitPrice ?? 10_000, discount: opts.discount });
+ return { app, id };
+}
+
+describe("credit notes", () => {
+ it("numbers credit notes sequentially and lists them per invoice", async () => {
+ const { app, id } = await setup();
+ const first = await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 2_500 });
+ const second = await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 1_000 });
+ expect(first.status).toBe(201);
+ expect(first.body).toMatchObject({ number: "CN-0001", invoiceId: id, amount: 2_500, currency: "EUR" });
+ expect(second.body).toMatchObject({ number: "CN-0002" });
+ const list = await app.handle("GET", `/invoices/${id}/credit-notes`);
+ expect((list.body as { number: string }[]).map((n) => n.number)).toEqual(["CN-0001", "CN-0002"]);
+ });
+
+ it("rejects bad amounts (400) and amounts above what is left (409)", async () => {
+ const { app, id } = await setup({ discount: 1_000 });
+ for (const amount of [0, -5, 1.5, "10", undefined]) {
+ expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount })).status).toBe(400);
+ }
+ await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 8_000 });
+ expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 1_001 })).status).toBe(409);
+ expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 1_000 })).status).toBe(201);
+ });
+
+ it("refuses drafts and unknown invoices", async () => {
+ const app = testApp();
+ const customerId = await seedCustomer(app);
+ const draft = await app.handle("POST", "/invoices", {
+ customerId,
+ currency: "EUR",
+ lines: [{ description: "x", quantity: 1, unitPrice: 100 }],
+ });
+ const id = (draft.body as { id: string }).id;
+ expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 10 })).status).toBe(409);
+ expect((await app.handle("GET", "/invoices/inv_999/credit-notes")).status).toBe(404);
+ });
+
+ it("reduces the outstanding report for open invoices", async () => {
+ const { app, id } = await setup();
+ await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 4_000 });
+ const report = await app.handle("GET", "/reports/outstanding");
+ expect(report.body).toMatchObject({ totals: { EUR: 6_000 }, count: 1 });
+ });
+
+ it("voids a paid invoice by crediting what is left", async () => {
+ const { app, id } = await setup();
+ await app.handle("POST", `/invoices/${id}/pay`);
+ await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 3_000 });
+ const res = await app.handle("POST", `/invoices/${id}/void`);
+ expect(res.status).toBe(200);
+ expect(res.body).toMatchObject({ status: "void" });
+ const notes = (await app.handle("GET", `/invoices/${id}/credit-notes`)).body as { amount: number }[];
+ expect(notes.map((n) => n.amount)).toEqual([3_000, 7_000]);
+ });
+
+ it("voids a fully credited paid invoice without another note", async () => {
+ const { app, id } = await setup();
+ await app.handle("POST", `/invoices/${id}/pay`);
+ await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 10_000 });
+ expect((await app.handle("POST", `/invoices/${id}/void`)).status).toBe(200);
+ const notes = (await app.handle("GET", `/invoices/${id}/credit-notes`)).body as unknown[];
+ expect(notes).toHaveLength(1);
+ });
+
+ it("refuses credit notes on void invoices and double voids", async () => {
+ const { app, id } = await setup();
+ await app.handle("POST", `/invoices/${id}/pay`);
+ await app.handle("POST", `/invoices/${id}/void`);
+ expect((await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 1 })).status).toBe(409);
+ expect((await app.handle("POST", `/invoices/${id}/void`)).status).toBe(409);
+ });
+
+ it("migrates a v1 file by adding the credit note list and counter", () => {
+ const data = migrate({
+ schemaVersion: 1,
+ counters: { customer: 1, invoice: 1, invoiceNumber: 1 },
+ customers: [],
+ invoices: [],
+ });
+ expect(data.creditNotes).toEqual([]);
+ expect(data.counters).toEqual({ customer: 1, invoice: 1, invoiceNumber: 1, creditNote: 0 });
+ expect(openStore().nextId("creditNote")).toBe(1);
+ });
+});
diff --git a/test/invoice.test.ts b/test/invoice.test.ts
index 85202f2..4ad9677 100644
--- a/test/invoice.test.ts
+++ b/test/invoice.test.ts
@@ -53,9 +53,10 @@ describe("invoice domain", () => {
expect(() => markPaid(draft({ status: "void" }), NOW)).toThrow(ConflictError);
});
- it("voids drafts and open invoices, never paid ones", () => {
+ it("voids drafts, open and paid invoices, never void ones", () => {
expect(voidInvoice(draft(), NOW).status).toBe("void");
- expect(() => voidInvoice(draft({ status: "paid" }), NOW)).toThrow(ConflictError);
+ expect(voidInvoice(draft({ status: "paid" }), NOW).status).toBe("void");
+ expect(() => voidInvoice(draft({ status: "void" }), NOW)).toThrow(ConflictError);
});
it("knows when an open invoice is overdue", () => {
sessionB-F2.diff é o código da sessão nova que rodou o mesmo pedido de novo.
sessionB-F2.diff
diff --git a/README.md b/README.md
index 890f13c..3aa7a58 100644
--- a/README.md
+++ b/README.md
@@ -28,3 +28,5 @@ pnpm typecheck # tsc --noEmit
## Invoice lifecycle
`draft` → (`issue`) → `open` → (`pay`) → `paid`; `draft`/`open` → (`void`) → `void`.
+A `paid` invoice is voided by crediting whatever is left on it (credit notes `CN-0001`, ..., via
+`POST /invoices/:id/credit-notes` `{ "amount": cents }`; list with `GET`), then it becomes `void`.
diff --git a/src/domain/credit-note.ts b/src/domain/credit-note.ts
new file mode 100644
index 0000000..e2047c3
--- /dev/null
+++ b/src/domain/credit-note.ts
@@ -0,0 +1,39 @@
+import { ConflictError, ValidationError } from "./errors";
+import { computeTotals, type Invoice } from "./invoice";
+import { assertCents, type Cents, type Currency, sum } from "./money";
+
+export type CreditNote = {
+ id: string;
+ /** CN-0001, CN-0002, ... */
+ number: string;
+ invoiceId: string;
+ currency: Currency;
+ /** cents, always > 0 */
+ amount: Cents;
+ createdAt: string;
+};
+
+/** What can still be credited on an invoice: its total minus the credit notes already issued. */
+export function remainingCredit(invoice: Invoice, notes: CreditNote[]): Cents {
+ return computeTotals(invoice).total - sum(notes.map((n) => n.amount));
+}
+
+/** Checks a credit-note request against the invoice and returns the amount. Throws before any number is taken. */
+export function parseCreditAmount(body: unknown, invoice: Invoice, notes: CreditNote[]): Cents {
+ if (typeof body !== "object" || body === null) {
+ throw new ValidationError("body must be an object");
+ }
+ const amount = assertCents((body as Record<string, unknown>).amount, "amount", { min: 1 });
+ if (invoice.status !== "paid") {
+ throw new ConflictError(`invoice ${invoice.id} is ${invoice.status}, only paid invoices can be credited`);
+ }
+ const remaining = remainingCredit(invoice, notes);
+ if (amount > remaining) {
+ throw new ConflictError(`amount ${amount} exceeds the ${remaining} left to credit on invoice ${invoice.id}`);
+ }
+ return amount;
+}
+
+export function creditNumber(n: number): string {
+ return `CN-${String(n).padStart(4, "0")}`;
+}
diff --git a/src/domain/invoice.ts b/src/domain/invoice.ts
index 5b69fc9..60be8ac 100644
--- a/src/domain/invoice.ts
+++ b/src/domain/invoice.ts
@@ -52,8 +52,9 @@ export function markPaid(invoice: Invoice, now: Date): Invoice {
return { ...invoice, status: "paid", paidAt: now.toISOString() };
}
-export function voidInvoice(invoice: Invoice, now: Date): Invoice {
- if (invoice.status === "paid" || invoice.status === "void") {
+/** A paid invoice can be voided only once it is fully credited (`fullyCredited`). */
+export function voidInvoice(invoice: Invoice, now: Date, opts: { fullyCredited?: boolean } = {}): Invoice {
+ if ((invoice.status === "paid" && !opts.fullyCredited) || invoice.status === "void") {
throw new ConflictError(`invoice ${invoice.id} is ${invoice.status} and cannot be voided`);
}
return { ...invoice, status: "void", voidedAt: now.toISOString() };
diff --git a/src/http/context.ts b/src/http/context.ts
index c0a89d3..4b26d92 100644
--- a/src/http/context.ts
+++ b/src/http/context.ts
@@ -1,4 +1,5 @@
import type { Store } from "../store/json-store";
+import { creditNoteRepo } from "../store/credit-note-repo";
import { customerRepo } from "../store/customer-repo";
import { invoiceRepo } from "../store/invoice-repo";
@@ -7,8 +8,15 @@ export type AppContext = {
now: () => Date;
customers: ReturnType<typeof customerRepo>;
invoices: ReturnType<typeof invoiceRepo>;
+ creditNotes: ReturnType<typeof creditNoteRepo>;
};
export function createContext(store: Store, now: () => Date = () => new Date()): AppContext {
- return { store, now, customers: customerRepo(store), invoices: invoiceRepo(store) };
+ return {
+ store,
+ now,
+ customers: customerRepo(store),
+ invoices: invoiceRepo(store),
+ creditNotes: creditNoteRepo(store),
+ };
}
diff --git a/src/http/handlers/invoices.ts b/src/http/handlers/invoices.ts
index 09959e1..d393c34 100644
--- a/src/http/handlers/invoices.ts
+++ b/src/http/handlers/invoices.ts
@@ -1,3 +1,4 @@
+import { type CreditNote, creditNumber, parseCreditAmount, remainingCredit } from "../../domain/credit-note";
import { ValidationError } from "../../domain/errors";
import { type Invoice, type InvoiceStatus, issue, markPaid, voidInvoice } from "../../domain/invoice";
import { parseNewInvoice } from "../../domain/validation";
@@ -51,8 +52,39 @@ export function invoiceRoutes(router: Router, ctx: AppContext): void {
return { status: 200, body: invoiceView(ctx.invoices.save(paid)) };
});
+ router.on("POST", "/invoices/:id/credit-notes", ({ params, body }) => {
+ const invoice = ctx.invoices.get(params.id);
+ const amount = parseCreditAmount(body, invoice, ctx.creditNotes.listForInvoice(invoice.id));
+ return { status: 201, body: ctx.creditNotes.insert(newCreditNote(ctx, invoice, amount)) };
+ });
+
+ router.on("GET", "/invoices/:id/credit-notes", ({ params }) => {
+ const invoice = ctx.invoices.get(params.id);
+ return { status: 200, body: ctx.creditNotes.listForInvoice(invoice.id) };
+ });
+
router.on("POST", "/invoices/:id/void", ({ params }) => {
- const voided = voidInvoice(ctx.invoices.get(params.id), ctx.now());
+ const current = ctx.invoices.get(params.id);
+ if (current.status !== "paid") {
+ return { status: 200, body: invoiceView(ctx.invoices.save(voidInvoice(current, ctx.now()))) };
+ }
+ // Paid invoice: credit whatever is left, then void it.
+ const left = remainingCredit(current, ctx.creditNotes.listForInvoice(current.id));
+ if (left > 0) ctx.creditNotes.insert(newCreditNote(ctx, current, left));
+ const voided = voidInvoice(current, ctx.now(), { fullyCredited: true });
return { status: 200, body: invoiceView(ctx.invoices.save(voided)) };
});
}
+
+/** Takes the next number: call only once the amount has been validated. */
+function newCreditNote(ctx: AppContext, invoice: Invoice, amount: number): CreditNote {
+ const n = ctx.store.nextId("creditNote");
+ return {
+ id: `cn_${n}`,
+ number: creditNumber(n),
+ invoiceId: invoice.id,
+ currency: invoice.currency,
+ amount,
+ createdAt: ctx.now().toISOString(),
+ };
+}
diff --git a/src/store/credit-note-repo.ts b/src/store/credit-note-repo.ts
new file mode 100644
index 0000000..c922142
--- /dev/null
+++ b/src/store/credit-note-repo.ts
@@ -0,0 +1,14 @@
+import type { CreditNote } from "../domain/credit-note";
+import type { Store } from "./json-store";
+
+export function creditNoteRepo(store: Store) {
+ return {
+ listForInvoice(invoiceId: string): CreditNote[] {
+ return store.read().creditNotes.filter((n) => n.invoiceId === invoiceId);
+ },
+ insert(note: CreditNote): CreditNote {
+ store.update((d) => ({ ...d, creditNotes: [...d.creditNotes, note] }));
+ return note;
+ },
+ };
+}
diff --git a/src/store/json-store.ts b/src/store/json-store.ts
index e1daef5..03df910 100644
--- a/src/store/json-store.ts
+++ b/src/store/json-store.ts
@@ -14,9 +14,10 @@ export type Store = {
function empty(): StoreData {
return {
schemaVersion: CURRENT_SCHEMA_VERSION,
- counters: { customer: 0, invoice: 0, invoiceNumber: 0 },
+ counters: { customer: 0, invoice: 0, invoiceNumber: 0, creditNote: 0 },
customers: [],
invoices: [],
+ creditNotes: [],
};
}
diff --git a/src/store/migrations.ts b/src/store/migrations.ts
index c8b73a9..e8545db 100644
--- a/src/store/migrations.ts
+++ b/src/store/migrations.ts
@@ -1,6 +1,6 @@
import type { StoreData } from "./types";
-export const CURRENT_SCHEMA_VERSION = 1;
+export const CURRENT_SCHEMA_VERSION = 2;
type RawData = Record<string, unknown> & { schemaVersion?: number };
type Migration = (data: RawData) => RawData;
@@ -21,9 +21,18 @@ const v0ToV1: Migration = (data) => {
};
};
+/** v1 -> v2: credit notes (`creditNotes` list and `counters.creditNote`). */
+const v1ToV2: Migration = (data) => ({
+ ...data,
+ schemaVersion: 2,
+ counters: { ...(data.counters as object), creditNote: 0 },
+ creditNotes: [],
+});
+
/** migrations[n] upgrades a file from version n to n + 1. */
const migrations: Record<number, Migration> = {
0: v0ToV1,
+ 1: v1ToV2,
};
export function migrate(raw: unknown): StoreData {
@@ -43,8 +52,9 @@ export function migrate(raw: unknown): StoreData {
}
return {
schemaVersion: CURRENT_SCHEMA_VERSION,
- counters: (data.counters as StoreData["counters"]) ?? { customer: 0, invoice: 0, invoiceNumber: 0 },
+ counters: (data.counters as StoreData["counters"]) ?? { customer: 0, invoice: 0, invoiceNumber: 0, creditNote: 0 },
customers: (data.customers as StoreData["customers"]) ?? [],
invoices: (data.invoices as StoreData["invoices"]) ?? [],
+ creditNotes: (data.creditNotes as StoreData["creditNotes"]) ?? [],
};
}
diff --git a/src/store/types.ts b/src/store/types.ts
index 222b191..a9d7277 100644
--- a/src/store/types.ts
+++ b/src/store/types.ts
@@ -1,7 +1,8 @@
+import type { CreditNote } from "../domain/credit-note";
import type { Customer } from "../domain/customer";
import type { Invoice } from "../domain/invoice";
-export type Counters = { customer: number; invoice: number; invoiceNumber: number };
+export type Counters = { customer: number; invoice: number; invoiceNumber: number; creditNote: number };
/** The shape of the JSON file at CURRENT_SCHEMA_VERSION. */
export type StoreData = {
@@ -9,4 +10,5 @@ export type StoreData = {
counters: Counters;
customers: Customer[];
invoices: Invoice[];
+ creditNotes: CreditNote[];
};
diff --git a/test/invoice.test.ts b/test/invoice.test.ts
index 85202f2..97ef4d9 100644
--- a/test/invoice.test.ts
+++ b/test/invoice.test.ts
@@ -53,9 +53,10 @@ describe("invoice domain", () => {
expect(() => markPaid(draft({ status: "void" }), NOW)).toThrow(ConflictError);
});
- it("voids drafts and open invoices, never paid ones", () => {
+ it("voids drafts and open invoices, paid ones only when fully credited", () => {
expect(voidInvoice(draft(), NOW).status).toBe("void");
expect(() => voidInvoice(draft({ status: "paid" }), NOW)).toThrow(ConflictError);
+ expect(voidInvoice(draft({ status: "paid" }), NOW, { fullyCredited: true }).status).toBe("void");
});
it("knows when an open invoice is overdue", () => {
diff --git a/test/numbering.test.ts b/test/numbering.test.ts
index a97d189..1fa4dd8 100644
--- a/test/numbering.test.ts
+++ b/test/numbering.test.ts
@@ -20,3 +20,34 @@ describe("credit note numbering", () => {
expect(next.body).toMatchObject({ number: "CN-0002" });
});
});
+
+describe("credit notes and voiding", () => {
+ it("lists credit notes and voids a paid invoice by crediting the rest", async () => {
+ const app = testApp();
+ const customerId = await seedCustomer(app);
+ const id = await seedOpenInvoice(app, { customerId, unitPrice: 10_000 });
+ await app.handle("POST", `/invoices/${id}/pay`);
+ await app.handle("POST", `/invoices/${id}/credit-notes`, { amount: 2_500 });
+
+ const voided = await app.handle("POST", `/invoices/${id}/void`);
+ expect(voided.status).toBe(200);
+ expect(voided.body).toMatchObject({ status: "void" });
+
+ const list = await app.handle("GET", `/invoices/${id}/credit-notes`);
+ expect((list.body as { number: string; amount: number }[]).map((n) => [n.number, n.amount])).toEqual([
+ ["CN-0001", 2_500],
+ ["CN-0002", 7_500],
+ ]);
+ });
+
+ it("rejects bad amounts and unpaid invoices", async () => {
+ const app = testApp();
+ const customerId = await seedCustomer(app);
+ const id = await seedOpenInvoice(app, { customerId });
+ const url = `/invoices/${id}/credit-notes`;
+ expect((await app.handle("POST", url, { amount: 100 })).status).toBe(409);
+ await app.handle("POST", `/invoices/${id}/pay`);
+ expect((await app.handle("POST", url, { amount: 0 })).status).toBe(400);
+ expect((await app.handle("POST", url, {})).status).toBe(400);
+ });
+});
diff --git a/test/store.test.ts b/test/store.test.ts
index a1bf345..82cc59f 100644
--- a/test/store.test.ts
+++ b/test/store.test.ts
@@ -31,7 +31,7 @@ describe("store", () => {
writeFileSync(
file,
JSON.stringify({
- counters: { customer: 1, invoice: 1, invoiceNumber: 0 },
+ counters: { customer: 1, invoice: 1, invoiceNumber: 0, creditNote: 0 },
customers: [{ id: "cus_1", name: "Acme", email: "a@acme.io", createdAt: "2025-01-01T00:00:00.000Z" }],
invoices: [{ id: "inv_1", customer: { id: "cus_1", name: "Acme" }, status: "draft" }],
}),
Faça isto na segunda-feira
- Atualize o marketplace oficial, instale o pacote de skills no escopo do projeto e confira se o comando da retro aparece numa sessão nova.
- Rode sua tarefa real numa sessão comum. Deixe terminar e mantenha a sessão aberta.
- Rode a retro nessa sessão e depois rode de novo com a falha que você encontrou escrita em seguida.
- Faça a pergunta de rastreio: "For each candidate, quote the moment of this session's transcript that backs it; drop any candidate you cannot trace to a specific moment."
- Aprove os sobreviventes um de cada vez no seu suporte: uma checagem para uma falha mecânica, uma linha de padrões para uma decisão de julgamento, um comentário na origem para uma lacuna de navegação.
- Rode
/doctor prompt-auditcom o caminho dos arquivos que você mexeu, aplique as edições dele e depois commite os arquivos você mesmo. - Rode a mesma tarefa de novo numa sessão nova e veja a falha não acontecer.
Medições
São rodadas pequenas numa API de faturamento inventada (Node e TypeScript, TypeScript, vitest) com o Claude Code 2.1.294. São uma demonstração, não um benchmark. O teste escondido do financeiro tem cinco checagens escritas antes da rodada.
| Etapa | Resultado |
|---|---|
| Tarefa de nota de crédito, tentativa 1 | Limpa: 40 passaram, teste escondido do financeiro 5/5 (descartada, não é a sessão com defeito) |
| Tarefa de nota de crédito, tentativa 2 | 42 passaram, typecheck exit 0, teste escondido do financeiro 4/5. Veio CN-0004 onde era esperado CN-0002 |
| Primeira retro, sem falha informada | 5 itens ranqueados, abriu com "This session was smooth" |
| Rastreio da primeira retro | 2 sobreviventes, 3 descartados |
| Segunda retro, falha informada | 5 candidatos |
| Rastreio da segunda retro | 4 sobreviventes, 1 descartado |
| Aprovado na mão | 4 mudanças: hook, teste, linha de padrões, comentário na origem. Nenhuma linha no CLAUDE.md |
| Primeira tentativa de commit | O hook bloqueou: 1 falhou, 42 passaram (43). A árvore ainda tinha o código com bug |
| Depois da correção de uma linha | Suíte 43/43, teste escondido do financeiro 5/5, commits passaram |
| Sessão nova B, mesmo pedido | 37 passaram, typecheck exit 0, teste escondido do financeiro 5/5, números sem buracos depois de uma requisição rejeitada |
Leia com cuidado:
- Das duas rodadas comuns que fizemos nessa tarefa, uma entregou o bug antes da retro. Depois da retro temos uma única nova rodada, então isso é n=1.
- A sessão B leu o arquivo de padrões, o hook e o teste de numeração vermelho antes de escrever código. Ela recebeu a lição. A aprovação dela mostra o loop funcionando como projetado, não uma replicação independente.
- A retro nunca achou o bug sozinha. Sua primeira passada achou uma trava ausente que, nas palavras dela, não teria pego este bug.
- O novo hook checa a árvore de trabalho. Um
git cherry-pickdo commit da retro sobre a base não o executou. - Sem caminho, o prompt audit leu os arquivos de nível de usuário e não disse nada sobre os novos. Com o caminho do arquivo de padrões, respondeu que o arquivo estava limpo.
- A rota de emissão mais antiga desse repositório vaza números de fatura do mesmo jeito. Deixamos como está, fica fora do escopo desta sessão.
Para ir além
Leia quem roda um loop de lições de verdade. Um desenvolvedor reinjeta um arquivo de lições datado no início da sessão e transforma uma regra que fica escorregando num teste, numa regra de lint ou num hook, com um CLAUDE.md mantido como um roteador curto. s6
Leia as issues antes de confiar na retro. A issue 1173 é o argumento para o passo de rastreio. s7 A issue 1311 é o commit esquecido. s23 A issue 1158 é o comando ausente no marketplace oficial. s24
Aprenda onde os logs ficam e quanto tempo duram. A página de sessions cobre o caminho do transcript, retomar por caminho e a limpeza de 30 dias. s8
A auto memory é a alternativa automática. Deixamos de fora. O desabafo de um autor argumenta que ela escreve em silêncio, não tem versionamento e mistura trivialidades com regras duradouras, e por isso mantemos uma pessoa aprovando cada linha. s11 Trate isso como uma opinião e teste no seu próprio setup.
O /insights é o companheiro semanal. Ele monta um relatório HTML sobre até 200 sessões, com pontos de atrito e sugestões. s14 Um relato de campo transformou 64 sessões em 5 linhas de CLAUDE.md, 2 skills e hooks. s12 Não rodamos aqui.
O loop da própria Anthropic é manual. O post sobre o harness dela descreve o ajuste lendo os logs do avaliador, achando onde o julgamento dele divergiu e atualizando o prompt. s13 Não achamos nenhum comando ou post oficial de retro na primeira página do índice de engenharia. s27
Por que não automatizamos. Um gatilho de fim de sessão seria uma cola que nós mesmos escrevemos e não testamos. Hooks de fim de sessão não podem bloquear o encerramento e têm timeout padrão de 1,5 segundo, e o skill da retro é só invocado pelo usuário. s5 s1 A própria doc da retro diz que ela só propõe e que nada muda até você escolher um candidato. s2 Mantivemos a pessoa no loop.
O que deixamos fora do escopo. O mesmo bug de ordenação existe na rota antiga de emissão de faturas desse repositório, e uma retro nela seria uma rodada própria. Também não adicionamos um job de CI, porque nossa cópia não tinha remoto e um workflow nunca teria rodado.
FAQ
Por que a retro chamou minha sessão de smooth? Ela lê o log da sessão, e a sessão nunca soube que tinha falhado: seus testes e o typecheck estavam verdes. Rode de novo com o que falhou escrito depois do comando, como argumento.
A retro muda meus arquivos? Ela só propõe. Nada muda até você escolher um candidato. s2 Depois que você aprova, as mudanças podem ser implementadas mas não commitadas, então commite você mesmo. s23
Posso rodar numa sessão que já limpei?
Sim, se o log ainda estiver no disco. Os transcripts ficam em ~/.claude/projects/ e são limpos após 30 dias por padrão, e claude --resume <transcript-path> abre um. s8
Por que meu novo hook bloqueou o commit? Ele roda seu typecheck e seus testes na árvore de trabalho. Se a árvore ainda tem o bug que o teste agora pega, o commit é recusado. Corrija o código primeiro e depois commite.
Por que nenhuma linha no CLAUDE.md? As duas passadas da nossa retro recusaram uma, dizendo que um ponteiro custaria contexto a cada turno e ficaria desatualizado. A doc mira menos de 200 linhas e diz que o CLAUDE.md é contexto, não configuração aplicada. s4