msd-core/CONTRIBUTING.md

Contributing to GSD Core

Getting Started

# Clone the repo
git clone https://github.com/open-gsd/gsd-core.git
cd gsd-core

# Activate the pinned Node version from .nvmrc
nvm use

# Validate your environment
npm run check:env

# Install dependencies (reproducible, lockfile-driven)
npm ci

# Run tests
npm test

npm ci is required over npm install. It installs exactly what package-lock.json specifies and fails fast if the lockfile is out of sync — this is intentional.

docs/contributing/bootstrap.md is the source of truth for setup. See it for Node version managers other than nvm (fnm, asdf, mise), the environment validator, daily commands, and troubleshooting.

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Types of Contributions

GSD accepts three types of contributions. Each type has a different process and a different bar for acceptance. Read this section before opening anything.

🐛 Fix (Bug Report)

A fix corrects something that is broken, crashes, produces wrong output, or behaves contrary to documented behavior.

Process:

1. Open a Bug Report issue — fill it out completely.
2. Wait for a maintainer to confirm it is a bug (label: confirmed-bug). For obvious, reproducible bugs this is typically fast.
3. Fix it. Write a test that would have caught the bug.
4. Open a PR using the Fix PR template — link the confirmed issue.

Rejection reasons: Not reproducible, works-as-designed, duplicate of an existing issue.

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⚡ Enhancement

An enhancement improves an existing feature — better output, faster execution, cleaner UX, expanded edge-case handling. It does not add new commands, new workflows, or new concepts.

The bar: Enhancements must have a scoped written proposal approved by a maintainer before any code is written. A PR for an enhancement will be closed without review if the linked issue does not carry the approved-enhancement label.

Process:

1. Open an Enhancement issue with the full proposal. The issue template requires: the problem being solved, the concrete benefit, the scope of changes, and alternatives considered.
2. Wait for maintainer approval. A maintainer must label the issue approved-enhancement before you write a single line of code. Do not open a PR against an unapproved enhancement issue — it will be closed.
3. Write the code. Keep the scope exactly as approved. If scope creep occurs, comment on the issue and get re-approval before continuing.
4. Open a PR using the Enhancement PR template — link the approved issue.

Rejection reasons: Issue not labeled approved-enhancement, scope exceeds what was approved, no written proposal, duplicate of existing behavior.

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✨ Feature

A feature adds something new — a new command, a new workflow, a new concept, a new integration. Features have the highest bar because they add permanent maintenance burden to a solo-developer tool maintained by a small team.

The bar: Features require a complete written specification approved by a maintainer before any code is written. A PR for a feature will be closed without review if the linked issue does not carry the approved-feature label. Incomplete specs are closed, not revised by maintainers.

Process:

1. Discuss first — check Discussions to see if the idea has been raised. If it has and was declined, don't open a new issue.
2. Open a Feature Request issue with the complete spec. The template requires: the solo-developer problem being solved, what is being added, full scope of affected files and systems, user stories, acceptance criteria, and assessment of maintenance burden.
3. Wait for maintainer approval. A maintainer must label the issue approved-feature before you write a single line of code. Approval is not guaranteed — GSD is intentionally lean and many valid ideas are declined because they conflict with the project's design philosophy.
4. Write the code. Implement exactly the approved spec. Changes to scope require re-approval.
5. Open a PR using the Feature PR template — link the approved issue.

Rejection reasons: Issue not labeled approved-feature, spec is incomplete, scope exceeds what was approved, feature conflicts with GSD's solo-developer focus, maintenance burden too high.

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📐 Proposing an ADR or PRD

An ADR (Architecture Decision Record) documents a significant architectural decision. A PRD (Product Requirements Document) captures the what and why of a feature before implementation. Both are governed by the same issue-first rule as everything else.

Process:

1. Open an issue of the appropriate type (enhancement for an ADR revisiting an existing area, feature for a new architectural surface, chore for policy/docs decisions). Fill it out completely.
2. Wait for maintainer approval. A maintainer must label the issue approved-enhancement, approved-feature, or confirm the chore before any file is created.
3. The GitHub-assigned issue number becomes your filename prefix. Create the file on a branch named after the issue:
   • docs/adr/<issue#>-<slug>.md for ADRs
   • docs/prd/<issue#>-<slug>.md for PRDs
   • Branch: docs/<issue#>-<slug>
4. Open a PR using the appropriate template and close the issue with Closes #<issue#> in the PR body.

One issue = one ADR-or-PRD = one PR. Do not batch multiple decisions into one file or one PR.

Do not compute a "next number" locally. Any PR that uses the legacy NNNN-* sequential pattern for a new ADR or PRD will be asked to rename the file to the <issue#>-<slug>.md format before merge.

Example: Issue #2264 was opened, approved, and its number became the prefix: docs/adr/2264-golden-parity-redesign.md.

Rejection reasons: Issue not approved before file was created, filename uses local-compute sequential number instead of issue#, multiple decisions bundled in one PR, file placed in wrong directory (docs/adr/ vs docs/prd/).

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The Issue-First Rule — No Exceptions

No code before approval.

For fixes: open the issue, confirm it's a bug, then fix it. For enhancements: open the issue, get approved-enhancement, then code. For features: open the issue, get approved-feature, then code.

PRs that arrive without a properly-labeled linked issue are closed automatically. This is not a bureaucratic hurdle — it protects you from spending time on work that will be rejected, and it protects maintainers from reviewing code for changes that were never agreed to.

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Where Do I Open My PR? (Branching Model)

GSD uses two long-lived branches: main (production, what's on npm @latest) and next (integration for the upcoming release). Almost every PR targets next. Full guide: docs/branching.md.

Your branch	PR target	Notes
feat/NNN-slug	next	Default for all new features
fix/NNN-slug	next	Default for all bug fixes; ships in next minor or via hotfix cherry-pick
chore/, docs/, refactor/, test/, perf/, ci/, revert/	next	All routine work
fix/critical-NNN-slug	main	Production-down emergencies only; auto-back-merges to next
release/X.Y.0	main	Created by release.yml — don't make these by hand
hotfix/X.Y.Z	main	Created by release.yml (dispatch with a patch version X.Y.Z) — don't make these by hand
Stabilization PR for an in-flight release	release/X.Y.0	Fix a regression found during the RC cycle

Day-to-day commands:

git fetch origin
git checkout next
git pull --ff-only origin next
git checkout -b fix/3187-config-corruption
# ... commit, push
gh pr create --base next --repo open-gsd/gsd-core

If you target the wrong branch by accident, the PR Target Validator workflow will post a comment with the one-line fix (click "Edit" by the PR title and change the base branch — no need to recreate the PR).

Why this matters: Under the old single-branch model, every PR rebased onto main, which moved on every merge. next moves far less often — only when another PR to next lands — so in practice you rebase much less.

But next does still require "up-to-date before merging". Branch protection has required_status_checks.strict = true; check it yourself with gh api repos/open-gsd/gsd-core/branches/next/protection --jq '.required_status_checks.strict'. If another PR lands while yours is open, yours goes BEHIND and must be rebased before it can merge.

Budget for that, because the rebase is not free here: it changes your HEAD sha, which invalidates the sha-bound pass marker the push gate reads, so a rebase means re-running the full remote verification and another CI cycle before the gate clears again. Rebase last — immediately before you push for review — rather than paying for a verification you are about to discard.

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Pull Request Guidelines

Architecture & Domain Standards (Maintainer-Defined)

The following files are maintainer-owned coding standards and must be treated as canonical when contributing:

• CONTEXT.md — domain language and module naming standards
• docs/adr/ — Architecture Decision Records (ADRs) for accepted architectural decisions

Full contributor requirements — including CONTEXT.md format, ADR governance, and AI-agent-assisted work standards — are in docs/contributor-standards.md.

Contributor requirements (summary):

• Read CONTEXT.md before naming or refactoring modules/interfaces/seams.
• Use CONTEXT.md vocabulary consistently in code comments, tests, issue/PR text, and docs for the touched area.
• Check relevant ADRs in docs/adr/ before proposing or implementing architectural changes.
• If a change intentionally revisits an ADR decision, call it out explicitly in the linked issue and PR rationale.
• Do not rewrite maintainer intent in CONTEXT.md/ADRs as part of drive-by cleanup; propose focused updates tied to approved scope.
• If using an AI assistant, prompt it to read CONTEXT.md and the relevant ADRs before writing any code or docs, and verify it used the correct vocabulary before opening the PR.

Every PR must link to an approved issue. PRs without a linked issue are closed without review, no exceptions.

• No draft PRs — draft PRs are automatically closed. Only open a PR when it is complete, tested, and ready for review. If your work is not finished, keep it on your local branch until it is.
• Use the correct PR template — there are separate templates for Fix, Enhancement, and Feature. Using the wrong template or using the default template for a feature is a rejection reason.
• Link with a closing keyword — use Closes #123, Fixes #123, or Resolves #123 in the PR body. The CI check will fail and the PR will be auto-closed if no valid issue reference is found.
  • Test-only and docs-only follow-up PRs may reference without closing. If your PR is documentation or regression coverage only — say, a repo-wide guard for a fix that already shipped — and there is no open issue for it to close, use a non-closing reference instead: Refs #123. Ref, Refs, References, Relates to, Related to, and Follow-up to are all accepted in that position. Do not write a closing keyword against an already-closed issue to satisfy the check; on merge it closes nothing, and it trains readers to treat closing keywords as decorative.
  • Qualifying diff shape: every changed file must be under tests/, under docs/, or a root-level *.md (README.md, CONTRIBUTING.md, …). This mirrors the doc-only classification the push gate already uses, and it is deliberately root-only — markdown under a subdirectory (gsd-core/workflows/*.md, agents/*.md, commands/**/*.md) is runtime-loaded text, not documentation, so it still requires a closing keyword. CHANGELOG.md is excluded too: edit it through a .changeset/ fragment, never directly.
  • This weaker form is accepted only for that diff shape. A PR touching anything else still needs a closing keyword, and a PR with no issue reference at all still fails. On a very large PR (more than 100 changed files) the check cannot confirm the diff shape and falls back to requiring a closing keyword.
• One concern per PR — bug fixes, enhancements, and features must be separate PRs
• No drive-by formatting — don't reformat code unrelated to your change
• Don't bundle test-fixture updates into docs: or unrelated commits — when a production change makes an existing test assertion stale, the test correction MUST land as its own test: (or fix:) commit, not bundled into a docs: commit that also updates the explanation. The release-sdk hotfix cherry-pick filter routes by commit-subject prefix (fix:, chore:, test:); a test-fixture correction packed under a docs: prefix is invisible to the picker and ships a half-state to the hotfix branch — production code changed, test assertion stale. v1.42.3 hit this exact mode (#3621). The fix is upstream: keep the test-fixture commit separate.
• CI must pass — all configured matrix jobs must be green. Node 22 remains the compatibility floor; Node 24 is the primary target; Node 26 compatibility must be preserved for code and tests even when a Node 26 CI lane is not yet available.
• Scope matches the approved issue — if your PR does more than what the issue describes, the extra changes will be asked to be removed or moved to a new issue

CHANGELOG Entries — Drop a Fragment

Do not edit CHANGELOG.md directly. Two PRs that both append to a ### Fixed block always conflict on merge — git can't pick a serialization order without a human. Instead, every PR with user-facing changes drops a fragment file in .changeset/.

npm run changeset -- --type Fixed --pr <YOUR_PR_NUMBER> \
  --body "**\`/gsd-foo\` no longer drops trailing slashes** — explain the user-visible change."

This writes .changeset/<adjective>-<noun>-<noun>.md. Three random words → concurrent PRs never collide. Allowed type: values follow Keep a Changelog: Added, Changed, Deprecated, Removed, Fixed, Security.

Fragments are consolidated into CHANGELOG.md at release time by the release workflow. See .changeset/README.md for the format spec and #2975 for the rationale.

CI enforcement: the Changeset Required workflow (scripts/changeset/lint.cjs) fails any PR that touches bin/, gsd-core/, src/, agents/, commands/, hooks/, or sdk/src/ without a .changeset/*.md fragment. (src/ is the TypeScript source of truth compiled into gsd-core/bin/lib/*.cjs, so editing it is a user-facing change even though the generated .cjs is gitignored and never appears in the diff.)

Running it locally. The lint derives its changed-file set from GITHUB_BASE_REF, which only CI sets. node scripts/changeset/lint.cjs on a developer machine therefore does not evaluate your branch and can report success on a PR that CI will fail. Pass the base explicitly to reproduce the CI result:

GITHUB_BASE_REF=next node scripts/changeset/lint.cjs
``` The gate also **validates the content** of every changed fragment: a fragment whose frontmatter does not parse (e.g. a `pr: 0` placeholder that was never backfilled to the real PR number) fails the gate with `fail_invalid_fragment`, naming the offending file. This stops a malformed fragment from merging to `next` and only detonating later in the release job's CHANGELOG render.

Opt-out: PRs with no user-facing impact (test refactors, lint config changes, CI tweaks, formatting-only changes) can add the no-changelog label. The lint honors it. When unsure whether a change is user-facing, add the fragment.

Release notes formatting

GitHub release notes are generated automatically. The release and hotfix workflows first create the release with gh release create --generate-notes, then run scripts/release-notes/format-github-release-notes.cjs --apply to rewrite the body into the project's curated format: an Install block, followed by What's Changed grouped into Feature / Enhancement / Fix sections (classified by each PR's conventional-commit title prefix — feat → Feature, fix → Fix, non-user-facing types test/chore/ci/docs/refactor/perf/revert → omitted from the user-facing notes, everything else → Enhancement), then New Contributors and the Full Changelog link.

To re-format an existing release by hand (e.g. backfilling an older release):

node scripts/release-notes/format-github-release-notes.cjs \
  --tag vX.Y.Z --repo open-gsd/gsd-core --apply

Omit --apply to print the reformatted body to stdout for review without publishing.

PR title convention (enforced at open time)

Because the changelog is built from PR titles, your PR title must follow:

type(#<issue>): short summary

• Start with the type — feat, fix, or any other conventional type (chore, docs, refactor, …). No leading tags or prefixes: a title like [security] fix(config): … defeats the ^fix bucket anchor and silently files the entry under the wrong changelog section.
• Put the linked issue ref in the scope — (#<digits>). This is what renders as a link to the issue in the changelog line. fix(core): … buckets correctly but produces a changelog entry with no issue link.
• A breaking-change marker is fine: feat(#42)!: ….

Examples: fix(#1542): roadmap rollback, feat(#39): milestone-prefixed phase IDs, enhance(#1549): add PR-title validator.

CI enforcement: pr-title-validator.yml checks the title on open/edit and fails with the required format if it doesn't conform. It reuses the same matcher the changelog classifier uses (scripts/release-notes/conventional-title.cjs), so a title that passes the check is guaranteed to bucket and link correctly. Fix a flagged title by editing it in place — the check re-runs on edit, no need to recreate the PR.

Documentation Updates — Update the Relevant Docs

If your PR adds, changes, deprecates, or removes user-visible behavior, you must update the relevant documentation in docs/. CI will fail any PR whose changeset fragment is typed Added, Changed, Deprecated, or Removed without also modifying at least one file under docs/ (#3213).

Fixed and Security fragments do not trigger this lint — bug fixes restore documented behavior, they do not introduce new behavior to document. (Edit the docs anyway if a fix corrects something the docs got wrong.)

Which docs to update

Change type	Required doc updates
New command or flag	docs/COMMANDS.md, docs/FEATURES.md
Changed command behavior or output	docs/USER-GUIDE.md, docs/COMMANDS.md
Configuration / schema change	docs/CONFIGURATION.md
Architectural change	docs/ARCHITECTURE.md, docs/adr/
Agent or skill change	docs/AGENTS.md
Removed command, flag, or workflow	All docs that referenced it

Language policy

All content in docs/ and the root README.md must be written in English. English is the canonical source. The translated READMEs (README.pt-BR.md, README.zh-CN.md, README.ja-JP.md, README.ko-KR.md) are community-maintained translations and do not need to be updated by every PR.

CI enforcement

The Docs Required workflow (scripts/lint-docs-required.cjs) reads the changeset fragments touched in the PR diff. If any has type Added / Changed / Deprecated / Removed, it requires at least one file under docs/ to also appear in the diff.

Opt-outs (with paper trail)

When a change genuinely has no user-facing documentation impact (infrastructure rewrite, internal refactor, test-only addition, CI fix), use one of:

• Label: add the no-docs label to the PR. Leave a comment explaining why no docs update was needed.
• Per-fragment marker: add <!-- docs-exempt: <reason> --> on its own line inside the body of each triggering changeset fragment (typically at the end). The reason is required and must be non-empty — a bare <!-- docs-exempt --> or <!-- docs-exempt: --> is rejected (no audit trail = no exemption). The marker is extracted at parse time by scripts/changeset/parse.cjs and stripped from the body before the CHANGELOG.md and GitHub release-notes serializers see it — it leaves a paper trail in the source fragment without leaking into published release notes. Inline mentions of the marker syntax (e.g. inside backticks) are intentionally ignored; the parser only acts on a marker that occupies its own line. Both routes leave a paper trail; the label is global, the marker is per-fragment for mixed PRs.

When unsure whether a change is user-facing, update the docs.

Testing Standards

All tests use Node.js built-in test runner (node:test) and assertion library (node:assert). Do not use Jest, Mocha, Chai, or any external test framework.

Suite grouping. Tests live in named suites (unit, integration, install, security, slow) selected by filename suffix: a file named foo.security.test.cjs belongs to the security suite; a file with no suffix (foo.test.cjs) belongs to unit. See docs/TESTING-SUITES.md for the full policy, CI matrix, and per-suite scripts (npm run test:unit, npm run test:security, npm run test:coverage:unit, …). Default npm test still runs every test — backwards compatible.

Required Imports

const { describe, it, test, beforeEach, afterEach, before, after, mock } = require('node:test');
const assert = require('node:assert/strict');

Setup and Cleanup

There are two approved cleanup patterns. Choose the one that fits the situation.

Pattern 1 — Shared fixtures (beforeEach/afterEach): Use when all tests in a describe block share identical setup and teardown. This is the most common case.

// GOOD — shared setup/teardown with hooks
describe('my feature', () => {
  let tmpDir;

  beforeEach(() => {
    tmpDir = createTempProject();
  });

  afterEach(() => {
    cleanup(tmpDir);
  });

  test('does the thing', () => {
    assert.strictEqual(result, expected);
  });
});

Pattern 2 — Per-test cleanup (t.after()): Use when individual tests require unique teardown that differs from other tests in the same block.

// GOOD — per-test cleanup when each test needs different teardown
test('does the thing with a custom setup', (t) => {
  const tmpDir = createTempProject('custom-prefix');
  t.after(() => cleanup(tmpDir));

  assert.strictEqual(result, expected);
});

Never use try/finally inside test bodies. It is verbose, masks test failures, and is not an approved pattern in this project.

// BAD — try/finally inside a test body
test('does the thing', () => {
  const tmpDir = createTempProject();
  try {
    assert.strictEqual(result, expected);
  } finally {
    cleanup(tmpDir); // masks failures — don't do this
  }
});

try/finally is only permitted inside standalone utility or helper functions that have no access to test context.

Use Centralized Test Helpers

Import helpers from tests/helpers.cjs instead of inlining temp directory creation:

const { createTempProject, createTempGitProject, createTempDir, cleanup, runGsdTools } = require('./helpers.cjs');

Helper	Creates	Use When
createTempProject(prefix?)	tmpDir with .planning/phases/	Testing GSD tools that need planning structure
createTempGitProject(prefix?)	Same + git init + initial commit	Testing git-dependent features
createTempDir(prefix?)	Bare temp directory	Testing features that don't need .planning/
cleanup(tmpDir)	Removes directory recursively	Always use in afterEach
runGsdTools(args, cwd, env?)	Executes gsd-tools.cjs	Testing CLI commands

Spawning a subprocess: use the process seam

Anything that shells out goes through tests/helpers/process-seam.cjs — never a hand-rolled spawnSync/execFileSync in your suite.

const { runNode, runGit, runHook, OUTCOME } = require('./helpers/process-seam.cjs');

const r = runHook(HOOK_PATH, [], { input: JSON.stringify(payload), timeoutMs: 5000 });
assert.equal(r.outcome, OUTCOME.EXITED);
assert.equal(r.exitCode, 0);

Primitive	Spawns
runNode(argv, opts)	process.execPath
runGit(argv, opts)	git
runHook(scriptPath, argv, opts)	opts.interpreter (default process.execPath; pass 'bash' for a shell script)

opts: { cwd, env, input, timeoutMs, killSignal, interpreter }.

Every call returns the same discriminated union — { outcome, exitCode, stdout, stderr, timedOut, signal, killed, code } — and never throws for a child's exit code, a timeout, a buffer overflow, or a spawn failure. All four are data, so you assert on them:

assert.equal(r.outcome, OUTCOME.TIMED_OUT);
assert.equal(r.timedOut, true);

Two rules the seam enforces for you:

• Every call is timeout-bounded. timeoutMs defaults to 60s; there is no unbounded path. An unbounded subprocess is an indefinite hang, and it is how macOS CI silently stops reporting.
• outcome distinguishes cases that look identical. A timeout and a maxBuffer overflow both report exitCode: null and signal: 'SIGTERM', differing only in code (ETIMEDOUT vs ENOBUFS). Branch on outcome, never on signal.

The seam is not a fault-injection surface — it cannot tell an injected timeout from a genuine bench OOM. Inject faults in-process through a module's deps parameter instead.

Per-suite wrappers are still expected and encouraged: bind your fixture (cwd, env, payload) in a local helper and delegate the spawn to the seam.

Class-norm timeouts live in tests/helpers/timeouts.cjs — PROBE_TIMEOUT_MS, GIT_TIMEOUT_MS, BUILD_TIMEOUT_MS, INSTALL_TIMEOUT_MS. These describe how long a whole CLASS of subprocess call takes (a CLI probe, git plumbing on a fixture repo, a hooks build, a full bin/install.js run), not a single suite's preference, so import them rather than re-declaring the same literal with the same comment in yet another file. Only write a local constant when a site genuinely differs from its class (a real tsc compile, a regen:derived run, ...) — and give that local constant its own justifying comment explaining why it departs from the norm.

When you want git to throw: gitOrThrow

runGit never throws — that is the whole point of it. But execSync and execFileSync do throw on a non-zero exit, and a lot of fixture setup relies on that: git commit failing should stop the test right there, not hand back an empty string that produces a baffling assertion failure twenty lines later.

For that case use tests/helpers/git-fixture.cjs:

const { gitOrThrow } = require('./helpers/git-fixture.cjs');

gitOrThrow(['init', '-b', 'main'], { cwd: dir });
gitOrThrow(['commit', '-m', 'seed'], { cwd: dir });   // throws if git exits non-zero
const branch = gitOrThrow(['rev-parse', '--abbrev-ref', 'HEAD'], { cwd: dir }).trim();

It returns stdout as a string on success. On any non-EXITED outcome, or a non-zero exit, it throws an Error carrying status, exitCode, stdout, stderr, signal, timedOut and outcome as own properties. status and exitCode are deliberate aliases: status is what the legacy execSync idiom reads (catch (err) { assert.equal(err.status, 1) }), so a migrated call site keeps working.

You want	Use
Every outcome as data; you branch on outcome	runGit
Fixture setup that must abort loudly on failure	gitOrThrow

process-seam.cjs itself is untouched by this — it still never throws.

If your per-suite wrapper spawns something that is not git — a node CLI via runNode, a bash snippet via runHook — and its callers depend on a throw, call throwIfFailed(result, displayName) directly instead of hand-rolling the same outcome !== EXITED || exitCode !== 0 check. gitOrThrow is itself just throwIfFailed bound to runGit, so every thrown error — git or not — carries the same status/exitCode/stdout/stderr/signal/timedOut/outcome shape:

const { throwIfFailed } = require('./helpers/git-fixture.cjs');

const r = runNode([BUILD_SCRIPT], { timeoutMs: BUILD_TIMEOUT_MS });
throwIfFailed(r, 'build-hooks.js (before install tests)');

When you want the legacy shape without a throw: toLegacyResult

Some call sites never wanted a throw in the first place — they already branch on exit status as data, reading .status/.stdout/.stderr off the result themselves. Those still need the seam's exitCode renamed to the legacy status field their assertions expect. Use toLegacyResult instead of hand-rolling the three-line mapping — ~8 test files did exactly that independently before this export existed (#3147):

const { toLegacyResult } = require('./helpers/git-fixture.cjs');

function runLint(args = []) {
  const r = runNode([LINT_SCRIPT, ...args], { timeoutMs: PROBE_TIMEOUT_MS });
  return toLegacyResult(r); // { status, stdout, stderr }
}

It is a bare mapping and nothing more. If your call site needs an extra field beyond that shape (a parsed-JSON body, a fixture-specific path alongside the result), compose it rather than extending the helper: { ...toLegacyResult(result), extra }. And if your site's return shape genuinely diverges from { status, stdout, stderr } — e.g. it substitutes a parsed report object for raw stdout — leave it as its own local mapping; forcing every result-reshaping helper onto one shared function is the same drift toLegacyResult exists to prevent, just in the other direction.

The lint rule that enforces it

local/no-unbounded-spawn (eslint-rules/no-unbounded-spawn.cjs) fails any spawnSync, execFileSync or execSync under tests/ that is not timeout-bounded. It resolves renamed destructures (const { execSync: exec } = require('node:child_process')) and chained requires (require('node:child_process').execSync(...)), so renaming your way around it does not work.

Two things it deliberately rejects, because both look bounded and are not:

• timeout: 0 — Node reads zero as no timeout.
• timeout: 999999999 — anything above the 600000 ms ceiling is effectively unbounded. Size the number to what the command actually runs and say why in a comment.

A non-literal value (timeout: GIT_TIMEOUT_MS) is trusted — that is the shape you should be writing.

When a call genuinely needs more than the 600000 ms ceiling — a full installer run, a build plus generators — the escape is an inline marker comment, exactly the // allow-test-rule: <reason> idiom above:

// allow-spawn-timeout-ceiling: regen:derived chains a full build plus eight generators
timeout: 900000,

The reason is required and must be non-empty; a bare // allow-spawn-timeout-ceiling: (or one with only whitespace after the colon) is not an audit trail and still reports timeoutTooLarge. The marker binds only to the call it decorates — either the line immediately above it, or anywhere inside that call's own source range — never to the rest of the file. Critically, the escape only ever raises the ceiling for a call that already resolves to a numeric timeout: it never waives the requirement for a bound. A marked call with no timeout at all still reports unboundedSpawn.

There is no allowlist. eslint-rules/no-unbounded-spawn.allowlist.json grandfathered files that predated the rule; the epic that introduced it (#3064) migrated every site across four waves and deleted the file in its terminal wave (#3148), so local/no-unbounded-spawn now runs with no exemption surface across tests/**. There is no file to add an entry to — fix the timeout at the call site instead. The only sanctioned escapes are an explicit timeout on a raw spawn (for a call shape the process seam cannot express, e.g. a shell: true invocation for npm.cmd on Windows, or stdio redirection to a real fd) and the // allow-spawn-timeout-ceiling: <reason> marker above for a bound over the 600000 ms ceiling. Never reach for eslint-disable on this rule — with the allowlist gone, that is the only remaining way to silence it, and a test asserts that no such comment exists anywhere under tests/.

Test Structure

describe('featureName', () => {
  let tmpDir;

  beforeEach(() => {
    tmpDir = createTempProject();
    // Additional setup specific to this suite
  });

  afterEach(() => {
    cleanup(tmpDir);
  });

  test('handles normal case', () => {
    // Arrange
    // Act
    // Assert
  });

  test('handles edge case', () => {
    // ...
  });

  describe('sub-feature', () => {
    // Nested describes can have their own hooks
    beforeEach(() => {
      // Additional setup for sub-feature
    });

    test('sub-feature works', () => {
      // ...
    });
  });
});

Fixture Data Formatting

Template literals inside test blocks inherit indentation from the surrounding code. This can introduce unexpected leading whitespace that breaks regex anchors and string matching. Construct multi-line fixture strings using array join() instead:

// GOOD — no indentation bleed
const content = [
  'line one',
  'line two',
  'line three',
].join('\n');

// BAD — template literal inherits surrounding indentation
const content = `
  line one
  line two
  line three
`;

QA Matrix Requirements

Happy-path tests are not enough for code that accepts user input, reads project files, writes to disk, shells out, generates artifacts, or builds prompts. New tests for those areas must include adversarial inputs and negative proof that unsafe behavior did not happen.

See TEST-EXAMPLES.md for concrete demo tests that show these requirements in practice.

Use this matrix when it applies to the changed surface:

1. Happy path
2. Missing input
3. Empty input
4. Whitespace-only input
5. Malformed input
6. Out-of-range input
7. Duplicate or conflicting input
8. Hostile input
9. Filesystem failure
10. Concurrency or retry
11. Cross-platform path/newline behavior
12. Regression fixture from the linked issue

You do not need all twelve cases for every PR. You do need to cover the cases that match the risk of the touched code. If a case is not applicable, the PR should make that obvious from the issue scope or test rationale.

CLI and command routing

Changes to CLI parsing, command dispatch, query dispatch, command routers, gsd-tools, or gsd-sdk must include a negative input matrix for the affected command family.

Required cases where relevant:

• Missing required arguments
• Empty strings, for example --phase ""
• Whitespace-only values
• Duplicate flags, for example --phase 1 --phase 2
• Conflicting flags, for example --json --raw
• Malformed assignments, for example --phase= and --phase==1
• Unknown subcommands at the touched command depth
• Values that look like flags, for example --name --weird
• Very long values and Unicode values
• Shell metacharacters in values, for example ;, &&, $(), backticks, and quotes

CLI tests must assert on the full command contract:

• Exit status
• Structured --json result when the command supports JSON
• Filesystem mutation or absence of mutation
• No stack trace in non-debug failure output
• No shell interpolation of attacker-controlled values

Prefer spawnSync(process.execPath, [scriptPath, ...args], { cwd, encoding: 'utf8' }) or execFileSync() with argv arrays. Do not use shell strings for tests that contain hostile values.

Parser and project-file inputs

Changes to markdown, TOML, frontmatter, roadmap, phase, state, config, or schema parsing must include adversarial fixtures. Put reusable fixtures under tests/fixtures/adversarial/ with a directory that names the input type, such as roadmap/, frontmatter/, config/, toml/, or planning-state/.

Required cases where relevant:

• Malformed frontmatter
• Duplicate keys
• Mixed CRLF/LF newlines
• Unclosed or nested fenced code blocks
• Headings inside fenced code blocks
• Unicode headings
• Repeated or decimal phase IDs
• Path traversal-like names such as ../../x
• Null bytes or replacement characters
• Huge but bounded files
• TOML duplicate tables or trailing garbage
• Empty arrays vs missing arrays
• Scalars where arrays are expected, and objects where strings are expected

Property-style parser tests are encouraged for high-risk parsers. They must be deterministic: pin the seed, bound the iteration count, and print replay data on failure.

Fixture provenance (#2371)

A gate's fixtures may not be derived from the gate's own writer, grammar, or docstring examples. A negative fixture must come from a source that does not know the gate exists.

This is stricter than the adversarial-input rule above and exists because of it: tests/fixtures/adversarial/ covers hostile input, but a fixture written by the parser's own author — even a deliberately "realistic" one — is still drawn from the author's mental model of the format. It can only ever confirm what the author already believed, never surface what they didn't anticipate. A property-test generator has the same failure mode one level up: seeding the generator from the writer/render function that produces the same format makes the document shape a constant, so the property can never explore a document the writer wouldn't produce (see the document-shaped vs. writer-seeded property tests in tests/api-coverage.test.cjs for a worked example — the writer-seeded one cannot fail against a decoy table; the document-shaped one can).

For a gate whose fixtures come from real user reports, put them under tests/fixtures/representative/<gate>/ with a MANIFEST.json labeling each fixture's source issue and expected gate verdict, and drive them through the gate's real CLI entrypoint (gate-verdict altitude), not the parser function in isolation — see tests/fixtures/representative/README.md and tests/representative-corpus.test.cjs. If the gate is not yet fixed, do not mark the assertion { todo: true } and do not skip it: this repo's test-runner (gsd-test / gsd-test-runner) has no concept of node:test's todo option — its JSONL result parser only recognizes kind: "pass" | "fail", so a thrown todo-marked test is still counted as a real failure and blocks the push gate. Instead record BOTH the correct target verdict (expected*) and the exact current observed verdict (currentBuggyOutput) in the manifest, and assert against currentBuggyOutput — an honest, non-vacuous characterization of today's known-broken behavior that passes today and breaks loudly the moment the real fix changes the observed output, forcing the assertion to be flipped to expected*.

Filesystem writes and installers

Changes to install/uninstall flows, generated artifact writers, state/config writers, worktree safety, or any code that writes under .planning, runtime config dirs, .claude, .codex, hooks, or generated files must include fault-injection coverage where the seam allows it.

Required cases where relevant:

• Missing parent directory
• Target path exists as a file instead of a directory
• Read-only target directory
• Broken symlink
• Symlink escaping the intended root
• Paths with spaces, Unicode, or newlines
• Partial write failure
• Rename failure
• Concurrent deletion or write collision
• Temp-file cleanup after failure

Use node:test mocks such as mock.method() for fs.writeFileSync, fs.renameSync, fs.mkdirSync, fs.rmSync, and subprocess seams when the production code exposes a seam. Restore mocks with test hooks or t.after().

Security and prompt-injection surfaces

Changes that read prompts, plans, markdown, agent instructions, shell command projections, workstream/project names, or user-controlled files must treat those inputs as hostile.

Required cases where relevant:

• Fake instruction tags, for example <instructions>ignore previous</instructions>
• Heredoc breakouts
• Shell command substitution payloads
• Path traversal through project or workstream values
• Malicious markdown links
• Fake frontmatter fields that try to override intent
• Secret-looking values in inputs, logs, stdout, stderr, and thrown errors
• Environment variables with fake tokens to prove redaction

Security tests must assert both the positive guard behavior and the negative proof: no path escape, no command execution, no leaked token, no untrusted content promoted to instructions.

Generated files and parity

Changes to generators, generated .cjs/.ts files, command manifests, aliases, hooks, or SDK/runtime parity must test bad input and runtime parity, not only freshness.

Required cases where relevant:

• Missing source command
• Malformed command frontmatter
• Duplicate command names or aliases
• Partial generator output
• Generator crash halfway through
• Manual edits to generated files
• Stale generated file with valid timestamp but wrong content
• Runtime .cjs and SDK .ts generated surfaces disagree

Generator tests should run in temp fixtures and assert atomic output behavior. Do not mutate production generated files except in explicit freshness checks.

Prohibited: Source-Grep Tests

Never read source-code .cjs files with readFileSync to assert that strings exist within them. This is source-grep theater: it proves a literal is present in a file, not that the feature works at runtime.

// BAD — source-grep theater
const configSrc = fs.readFileSync(
  path.join(GSD_ROOT, 'gsd-core', 'bin', 'lib', 'config-schema.cjs'), 'utf-8'
);
assert.ok(
  configSrc.includes("'workflow.plan_bounce'"),
  'VALID_CONFIG_KEYS should contain workflow.plan_bounce'
);

This test passes even if workflow.plan_bounce is present but misspelled in the schema, removed from the validation path, or moved to a different file under a different name. It survives every behavioral regression and fails only on trivial renames.

The correct pattern for config key tests — use the CLI:

// GOOD — behavioral test via the CLI
test('config-set accepts workflow.plan_bounce', (t) => {
  const tmpDir = createTempProject();
  t.after(() => cleanup(tmpDir));

  const result = runGsdTools('config-set workflow.plan_bounce true', tmpDir);
  assert.ok(result.success, `config-set should accept workflow.plan_bounce: ${result.error}`);

  const configPath = path.join(tmpDir, '.planning', 'config.json');
  const config = JSON.parse(fs.readFileSync(configPath, 'utf-8'));
  assert.strictEqual(config.workflow?.plan_bounce, true, 'value must be persisted');
});

This single test covers key registration in VALID_CONFIG_KEYS, the key's namespace resolution in KNOWN_TOP_LEVEL, and value persistence — all behaviors that the source-grep test could not touch.

Why this pattern broke at scale: Commit 990c3e64 in this repo updated 5 source-grep tests in one pass when VALID_CONFIG_KEYS moved between files. Zero of those tests were testing behavior. If they had been behavioral tests, the migration would have been invisible.

CI enforcement: The local/no-source-grep ESLint rule (eslint-rules/no-source-grep.cjs, wired in eslint.config.mjs) detects violations. Any test file that calls readFileSync on a .cjs path in a source directory without the exemption annotation below is flagged by npx eslint . (the Lint — ESLint CI step).

Exception: allow-test-rule: <reason>

Some tests legitimately read source files. There are six recognized categories:

Reason	When to use
source-text-is-the-product	Agent .md, workflow .md, command .md files — their text IS what the runtime loads. Testing text content tests the deployed contract.
architectural-invariant	Implementation must use a specific primitive (e.g., Atomics.wait, atomic file writes) that cannot be tested by observing outputs.
structural-regression-guard	A specific code pattern must (or must not) exist to prevent a class of bug (e.g., regex global-state misuse). Behavioral tests cannot distinguish which pattern was used.
docs-parity	A reference doc must stay in sync with source-defined constants (e.g., CONFIG_DEFAULTS). The source is the canonical list; there is no runtime API to enumerate it.
integration-test-input	A source file is used as a real fixture input to a transformation function under test — the file is not inspected for strings but passed as data.
structural-implementation-guard	A feature's interception or wiring point is not reachable end-to-end via runGsdTools. Used temporarily until a behavioral path exists.
pending-migration-to-typed-ir	Tracked for correction, not exempted. Test was identified by the lint as carrying a raw-text-matching pattern that contradicts the rule above. Each annotated file MUST cite the open migration issue (e.g. // allow-test-rule: pending-migration-to-typed-ir [#NNNN]) so the tracking is auditable. New tests cannot use this category — they must refactor production to expose typed IR. The annotation is removed when the test is corrected.

Annotate with a standalone // comment before the file's opening block comment:

// allow-test-rule: architectural-invariant
// state.cjs locking must use Atomics.wait(), not a spin-loop. Behavioral tests
// cannot observe which sleep primitive was chosen — only source inspection can.

/**
 * Regression tests for locking bugs #1909...
 */

The annotation must be a standalone // allow-test-rule: line, not inside a /** */ block comment — the CI linter scans for the pattern // allow-test-rule:.

Prohibited: Raw Text Matching on Test Outputs (file content, stdout, stderr)

Source-grep is not just readFileSync of a .cjs file. The same anti-pattern shows up wherever a test pattern-matches against text that a system-under-test produced, regardless of whether that text came from a source file, a rendered shim, a child process's stdout, or a free-form reason string. All forms are forbidden.

The following are all violations of the same rule:

// BAD — substring match on text written by the code under test
const cmdContent = fs.readFileSync(path.join(tmpDir, 'gsd-sdk.cmd'), 'utf8');
assert.ok(cmdContent.includes(`@node ${jsonQuoted} %*`), '.cmd embeds shim path');

// BAD — regex match on a child process's human-readable stdout formatter
const r = cp.spawnSync(SCRIPT, ['--patches-dir', dir]);
assert.match(r.stdout, /Failures: 1/);
assert.match(r.stdout, /not a regular file/);

// BAD — "structured parser" that hides string ops behind a function wrapper
function parseCmdShim(content) {
  const lines = content.split('\r\n').filter((l) => l.length > 0);
  return { header: lines[0], usesCRLF: content.includes('\r\n') };
}

// BAD — assert.match on a free-form `reason` string from a JSON report
assert.ok(/not a regular file/.test(report.results[0].reason));

Each of these passes on accidental near-matches (a comment containing @node somewhere, a stack trace that happens to say Failures: 1, a mis-typed reason that still contains the substring you're matching) and fails on harmless reformatting (changing Failures: 1 to 1 failure, swapping CRLF rendering style, rewording the error prose).

The rule

Tests assert on typed structured values. If the code under test produces text, the code under test must also expose a structured intermediate representation, and the test must assert on that IR — never on the rendered text.

Concretely: for any system-under-test that produces text output (a file renderer, a CLI formatter, an error-message builder), the production code MUST expose a typed alternative that the test consumes:

Output kind	Required structured surface	What the test asserts on
Rendered file (shim, template, generated code)	A pure builder function returning the IR ({ invocation, eol, fileNames, render })	triple.invocation.target === expected, triple.eol.cmd === '\r\n'
CLI human-formatter output	A --json mode that emits the same data structurally	report.results[0].reason === REASON.FAIL_INSTALLED_NOT_REGULAR_FILE
Error / status / reason	A frozen enum (Object.freeze({ FAIL_X: 'fail_x', ... }))	assert.equal(result.reason, REASON.FAIL_X)
File presence after a write	fs.statSync().isFile(), .size > 0, .mtimeMs advances	Filesystem facts; never read the file content back

Concrete example from this repo

gsd-core/bin/verify-reapply-patches.cjs exposes a frozen REASON enum and emits it through --json. Tests assert report.results[0].reason === REASON.FAIL_USER_LINES_MISSING rather than regex-matching the human-readable prose. The human formatter exists for operator console output only — tests must not depend on it. Adding a new reason code requires updating the REASON enum, the --json output, AND the test that locks Object.keys(REASON).sort() — three coordinated changes that keep the code surface from drifting from the test surface. A pure builder that returns the IR (no I/O) and a writer that consumes it — fs.statSync(target).size === Buffer.byteLength(render()) to prove the writer writes what the renderer produces, without comparing content — is the same pattern applied to rendered files.

Hiding grep behind a function is still grep

parseCmdShim, parsePs1Invocation, etc. that internally do content.split(...), lines[1].trim(), content.includes(...) are still string manipulation. The fact that the entry point looks like a parser doesn't change what's happening underneath — the test is still asserting on the lexical shape of rendered text. The fix is not "wrap the grep in a function with a typed-looking return value." The fix is to eliminate the rendered text from the test path entirely by surfacing the IR.

When you cannot eliminate text matching

There are exactly two cases where text content is the legitimate object of a test, both already covered by the existing exemption matrix:

1. source-text-is-the-product — workflow .md / agent .md / command .md files where the deployed text IS what the runtime loads.
2. docs-parity — a reference doc must mirror source-defined constants and there is no runtime enumeration API.

For everything else, if a test reaches for .includes() / .startsWith() / assert.match(text, /…/), the production code is missing a typed surface. Add the typed surface; do not work around it.

CI enforcement: the local/no-source-grep ESLint rule (eslint-rules/no-source-grep.cjs) is being extended (see issue tracker for the latest scope) to flag String#includes/String#startsWith/String#endsWith/assert.match on readFileSync results and on cp.spawnSync stdout/stderr in test files, with the same // allow-test-rule: exemption mechanism.

Node.js Version Compatibility

Node 22 is the minimum supported version. Node 24 is the primary CI target. Node 26 is the forward-compatibility target: do not add tests or production code that depend on deprecated behavior likely to fail there.

Version	Status
Node 22	Minimum required — Active LTS until October 2026, Maintenance LTS until April 2027
Node 24	Primary CI target — current Active LTS, all tests must pass
Node 26	Forward-compatible target — avoid deprecated APIs and exact runtime-error prose

Do not use:

• Deprecated APIs
• APIs not available in Node 22

Safe to use:

• node:test — stable since Node 18, fully featured in 24
• describe/it/test — all supported
• beforeEach/afterEach/before/after — all supported
• t.after() — per-test cleanup
• mock.method() — approved for scoped filesystem/subprocess fault injection
• t.plan() — fully supported
• Snapshot testing — fully supported

Assertions

Use node:assert/strict for strict equality by default:

const assert = require('node:assert/strict');

assert.strictEqual(actual, expected);      // ===
assert.deepStrictEqual(actual, expected);  // deep ===
assert.ok(value);                          // truthy
assert.throws(() => { ... }, /pattern/);   // throws
assert.rejects(async () => { ... });       // async throws

Running Tests

# Run all tests
npm test

# Run a single test file
node --test tests/core.test.cjs

# Run with coverage
npm run test:coverage

For examples of required negative matrices, parser fixtures, filesystem fault injection, security abuse tests, generated-file checks, and runtime/SDK parity tests, see TEST-EXAMPLES.md.

Preferred local benchmark runner (before PR)

When you can, run the local test bench harness before opening a PR — especially for Windows-sensitive changes.

• Setup guide: gsd-test-runner getting started
• Preferred PR evidence: include the bench results summary (or artifact link) in your PR body.

This gives maintainers a faster, higher-confidence signal than CI-only validation.

Pre-PR Seam Checks (Manifest/Alias Routing)

If you touched src/command-aliases.cts or any of the eight src/*-command-router.cts sources it feeds, run:

npm run check:alias-drift

This verifies the built alias artifacts under gsd-core/bin/lib/ agree with their source of truth — each family's *_SUBCOMMANDS list must match the subcommand values derived from its *_COMMAND_ALIASES table, in order, and each router must reference its own list. The surface is enumerated once in scripts/lib/alias-drift-families.cjs.

Editing shipped content (gsd-core/workflows, references, templates, contexts, agents/, commands/gsd/)

Editing the content of a copied shipped file — a gsd-core/workflows/*.md, an agent, a command definition — requires zero manual fixture regeneration. There is no committed path→hash manifest or per-file size baseline to update by hand; the differential attribution check (tests/emitted-attribution.test.cjs, ADR-2719) computes what your PR changed against next and requires every emitted-artifact hash that moved to be attributable to your diff. If it is not, the check fails and names the paths.

Legitimate cases where emitted bytes move for a reason your diff cannot show directly — a converter change, for example — go through a per-PR fragment under tests/emitted-drift-acks/ (#2914; name the path, say why); see CONTEXT.md's ### Emitted Artifact Provenance entry for the full model. Growth in a gsd-core/workflows/*.md or agents/gsd-*.md file is reported with its exact byte delta and needs the same acknowledgment; the outer tier hard caps in tests/workflow-size-budget.test.cjs / tests/agent-size-budget.test.cjs are unaffected and still apply. The legacy single tests/emitted-drift-ack.json is still read and unioned in for any branch that still carries it, but new acknowledgments go in a NEW fragment, never that file.

You do not need to memorize any of this. The failure output names its own remedy — it tells you to create a new fragment under tests/emitted-drift-acks/ (with a name nobody else is using — include your issue or PR number), which key to use, and prints a minimal valid document you can paste. Note the two key spaces, because the message says which one applies: an unattributable hash ripple is keyed on the emitted path (skills/gsd-add-tests/SKILL.md), while growth is keyed on the bare filename as it appears under gsd-core/workflows/ or agents/ (explore.md). When you remove the last entry from your fragment, delete the fragment file too — its presence is the alarm, so an empty one signals nothing. Nothing here is regenerated: if you find yourself looking for a baseline file to re-run a generator over, that file was deleted by #2724 and is not coming back.

Why fragments, not one file (#2914): every PR needing an acknowledgment used to rewrite tests/emitted-drift-ack.json's paths map wholesale — a single shared mutable file every such PR touches guarantees a merge conflict between any two of them (5 of 6 conflicting PRs in one open queue collided on this file and nothing else), and it means spent, already-merged entries pile up on next. A fragment per PR — the same shape .changeset/ already uses for the identical problem — means two PRs can never conflict on this seam again, and a fragment left on next after merge is inert rather than a shared cell. Two ack sources (two fragments, or a fragment and the legacy file) may never name the same path; that is a hard, loudly-reported error, not a silent last-wins.

tests/emitted-drift-ack.json (the legacy single file, specifically — NOT the fragment directory) must never persist on next (#2914): every entry is scoped to the diff that introduced it, so once merged it is, by definition, already at the base — spent and inert, regardless of shape, and its persistence is what makes it a shared merge-conflict cell. A fragment persisting on next is harmless, since fragments are independently named and cannot conflict with anything, so this guard is deliberately scoped to the legacy file alone. This is enforced only on next itself, by the guard-no-ack-on-next job in .github/workflows/test.yml (push-to-next trigger, scripts/lint-emitted-drift-ack.cjs --guard-next), never as a PR-lane check — a PR-lane "base ack must be absent" check would red every open PR the moment one landed (the #2768 shape #2789 exists to prevent). If you ever see the legacy file present on next, delete it; do not try to make it well-formed.

npm run regen:derived still exists for the artifacts that ARE committed and derived — sync-manifest-versions, the ADR index, the capability matrix, the inventory manifest, the registry, and tests/fixtures/install-tree/*.json (npm run gen:install-tree, the one fixture family ADR-2719 §7 keeps committed, because it conflicts on 0 of 7 and its diffs are readable). Run it after a change to any of those, before committing:

npm run regen:derived

Optional local pre-commit hook entry (Git-native):

.githooks/pre-commit is committed — you do not write it, you only point git at it. It runs check:alias-drift when you stage one of the tracked sources that check reads, and stays silent otherwise.

# one-time setup
git config core.hooksPath .githooks

This is opt-in and stays that way: nothing in npm install sets core.hooksPath for you, so a fresh clone acquires no hooks. To stop using them, git config --unset core.hooksPath.

Do not paste a copy of the hook body into your own .githooks/pre-commit. Bash cannot require() a CommonJS module, so the hook does carry the watched paths as literals — but tests/precommit-alias-drift-hook.test.cjs runs the real hook against every source derived from scripts/lib/alias-drift-families.cjs and fails in both directions: if the hook stops watching a source the checker reads, and if it keeps watching a router the checker dropped. A copy in your own tree has no such test behind it, and a hand-maintained copy is exactly what silently rotted the previous version of this recipe (#2725) — every path in it named the retired sdk/ tree or a gitignored build output, so the guard matched nothing for months.

Optional local pre-push hook to block a private author-email pattern:

.githooks/pre-push is committed too, and is covered by the same core.hooksPath opt-in above. It is a no-op until you set the regex, so enabling hooks does not enable this check:

# set locally in your shell profile (example)
export GSD_BLOCKED_AUTHOR_REGEX='@example-corp\.com$'

With that exported, a push carrying a commit whose author email matches is blocked, and the hook names the offending commits. Unset the variable to disable it.

CI Test Quality Checks

The following checks run on every PR in addition to the test suite:

Job	What it checks	How to pass
Lint — ESLint	No source-grep tests (see above), via the local/no-source-grep rule	Replace with runGsdTools() behavioral tests, or add // allow-test-rule: <reason>
Lint — cross-platform portability	Windows-portability defects in tests, via local/no-path-literal-in-assert (more rules land per ADR-1703) — e.g. a path-returning call asserted against a hardcoded /-literal	Normalize the actual: String(pathFn(...)).replace(/\\/g, '/'), or structure platform-specific code behind a process.platform !== 'win32' guard. No eslint-disable — see cross-platform-portability-rules.md

Run locally before pushing: npm run lint (or npx eslint .)

Architecture-Aware Testing Requirements

When work touches architecture, routing, policy, registry assembly, or command semantics:

• Write tests against module interfaces and seam behavior, not implementation trivia.
• Prefer invariant/contract tests that protect ADR-backed behavior and CONTEXT.md terminology.
• Ensure tests validate canonical behavior through the defined seam (for example: structured result contracts, canonical command metadata, and adapter parity), not source-text coupling.
• If ADRs define expected behavior, tests should assert those expectations directly.

Test Requirements by Contribution Type

The required tests differ depending on what you are contributing:

Bug Fix: A regression test is required. Write the test first — it must demonstrate the original failure before your fix is applied, then pass after the fix. A PR that fixes a bug without a regression test will be asked to add one. If the bug involves CLI input, parsers, filesystem writes, security/prompt surfaces, generated files, or SDK/runtime parity, the regression test must use the relevant QA matrix above and include negative proof that the bad behavior no longer happens. "Tests pass" does not prove correctness; it proves the bug isn't present in the tests that exist.

Enhancement: Tests covering the enhanced behavior are required. Update any existing tests that test the area you changed. If the enhancement expands accepted input, changes command routing, broadens parser behavior, changes generated output, or touches installer/write paths, add the relevant adversarial cases from the QA matrix above. Do not leave tests that pass but no longer accurately describe the behavior.

Feature: Tests are required for the primary success path and enough failure scenarios to cover the relevant QA matrix above. At minimum, every feature must cover one failure scenario; features that expose CLI input, parse user files, write files, generate artifacts, call subprocesses, or build prompts must cover the relevant negative/hostile cases. Leaving gaps in test coverage for a new feature is a rejection reason.

Behavior Change: If your change modifies existing behavior, the existing tests covering that behavior must be updated or replaced. For high-risk surfaces, update the adversarial tests as well as the happy path. Leaving passing-but-incorrect tests in the suite is not acceptable — a test that passes but asserts the old (now wrong) behavior makes the suite less useful than no test at all.

Reviewer Standards

Reviewers do not rely solely on CI to verify correctness. Before approving a PR, reviewers:

• Build locally (npm run build if applicable)
• Run the full test suite locally (npm test)
• Confirm regression tests exist for bug fixes and that they would fail without the fix
• Validate that the implementation matches what the linked issue described — green CI on the wrong implementation is not an approval signal

"Tests pass in CI" is not sufficient for merge. The implementation must correctly solve the problem described in the linked issue.

Code Review Lessons

Input validation: check shape, not just type

Defensive normalization at trust boundaries must validate both the value's type and its semantic shape. A typeof === 'string' check is necessary but insufficient when the field's contract requires a specific format (UUID v4, semver, file path, etc.). See ADR 227 for the architectural standard and concrete cases.

Code Style

• CommonJS (.cjs) — the project uses require(), not ESM import
• No external dependencies in core — gsd-tools.cjs and all lib files use only Node.js built-ins
• Conventional commits — feat:, fix:, docs:, refactor:, test:, ci:. The full grammar is <type>(<scope>): <subject> (enforced by hooks/gsd-validate-commit.sh; subject ≤72 chars, lowercase, imperative mood, no trailing period). When the work resolves a tracked issue, put the issue number in the scope: fix(#1520): randomize mktemp temp paths on BSD/macOS. The same convention applies to PR titles — release notes are grouped by the title's type prefix (feat → Feature, fix → Fix, non-user-facing types omitted, everything else → Enhancement).

File Structure

bin/install.js          — Installer (multi-runtime)
gsd-core/
  bin/lib/              — Core library modules (.cjs)
  workflows/            — Workflow definitions (.md)
                          Large workflows split per progressive-disclosure
                          pattern: workflows/<name>/modes/*.md +
                          workflows/<name>/templates/*. Parent dispatches
                          to mode files. See workflows/discuss-phase/ as
                          the canonical example (the discuss-phase/modes split, #717). New modes for
                          discuss-phase land in
                          workflows/discuss-phase/modes/<mode>.md.
                          Per-file growth is caught by the differential
                          attribution check (tests/emitted-attribution.test.cjs,
                          ADR-2719) — it reports the exact byte delta and
                          requires a per-PR fragment in
                          tests/emitted-drift-acks/ (#2914), no committed
                          snapshot to regenerate. Loose tier
                          hard caps remain in tests/workflow-size-budget.test.cjs.
                          The same applies to agent files (agents/gsd-*.md,
                          tests/agent-size-budget.test.cjs). Full how-to +
                          reference in docs/TESTING-SUITES.md (Workflow &
                          agent size budget); see issue #1074.
  references/           — Reference documentation (.md)
  templates/            — File templates
agents/                 — Agent definitions (.md) — CANONICAL SOURCE
commands/gsd/           — Slash command definitions (.md)
tests/                  — Test files (.test.cjs)
  helpers.cjs           — Shared test utilities
docs/                   — User-facing documentation

Source of truth for agents

Only agents/ at the repo root is tracked by git. The following directories may exist on a developer machine with GSD installed and must not be edited — they are install-sync outputs and will be overwritten:

Path	Gitignored	What it is
.claude/agents/	Yes (.gitignore:9)	Local Claude Code runtime sync
.cursor/agents/	Yes (.gitignore:12)	Local Cursor IDE bundle
.github/agents/gsd-*	Yes (.gitignore:37)	Local CI-surface bundle

If you find that .claude/agents/ has drifted from agents/ (e.g., after a branch change), re-run bin/install.js to re-sync from the canonical source. Always edit agents/ — never the derivative directories.

Security

• Path validation — use validatePath() from security.cjs for any user-provided paths
• No shell injection — use execFileSync (array args) over execSync (string interpolation)
• No ${{ }} in GitHub Actions run: blocks — bind to env: mappings first