* refactor(#3471): one enforcement point for the empty case, and reports that match the disk Implements ADR-3408 section 8.5 and section 8.4's residue (folded in when Phase 3 closed as subsumed). Four items, and two findings the design did not predict. FINDING 1 — the guards could not simply be deleted, as the design instructed. state sync and REGENERATE_STATE never run applyStatePreservation at all, so those six conditions were their ONLY empty-field fallback. A baseline probe on the unedited tree confirmed unconditional deletion drops current_phase, current_phase_name, current_plan, stopped_at and paused_at from a blank-body STATE.md on state sync — breaking the byte-identical requirement section 8.3 grants those two sanctioned-permanent exceptions. They are now GATED, not deleted: on for the exceptions, off for the write seam, where an empty derived value finally reaches the executor unmolested. FINDING 2, the more serious one — there was a FOURTH encoding of this policy. The pre-existing #2202 unknown-key carry-forward loop independently restored the same six fields whenever derivedFm lacked the key, completely neutralizing the fix. It is named nowhere in the ADR, the design, or three prior phases. It was found only because a probe that should have passed did not: the first attempt reported divergedFields: [] and silently restored both fields, reproducing the exact bug this phase exists to close. That is worth stating plainly. This epic's thesis is 'policy declared in one table, enforcement hand-rolled per call site.' The final phase found one more call site than anyone had counted — which is the fourth consecutive time a copy count in this epic proved to be a lower bound. Also: divergedFields could only observe fields the executor actively RESTORED, by diffing postFm. A discard-to-empty is absent both before and after, so it was invisible. A second pass now reports it, which is what makes section 8.5's 'preservation is visible' true for the delete-the-body-line case rather than aspirational. cmdPhaseComplete now reports what it preserved — #3374 was filed against that command and its complaint was warnings: [], silence. cmdStateJson's private third copy of the guards is routed onto the executor's preserve-when-unchanged rule. A read is definitionally not a write, so the #1230 delta is 'unchanged' and curated wins over a stale annotation. shouldPreserveExistingProgress is a different rule and is untouched. Report reconciliation is ONE shared helper across seven commands, not five copies of fix(#3351)'s block. Five copies of a reconciliation is precisely the shape this epic removes, and introducing it in the final phase would have been a poor joke. Both untraced commands were traced rather than assumed: cmdStatePlannedPhase matched cmdStateBeginPhase exactly; cmdStateCompletePhase turned out to be a different legacy hand-rolled path reporting a mix of field names AND a section name, where the naive helper would have dropped 'Current Position' as a false negative every time. * test(#3471): characterization coverage for one enforcement point and reconciled reports Matrix sections A-E, asserted at the consumer's output per ADR-3180 Decision 4(b)/(c) — this phase owes Decision 5's outcome metric, the one the drift guard's zero may never be reported without. Three walls matter more than the new coverage: A2 is SIX separately named tests, one per gated guard, not one parameterised assertion over a list. A list is trivially shortened later; six named tests are not, and six guards is exactly where a field gets silently dropped. A6 pins what Phases 1-3 already fixed — non-empty stale body, delta unchanged, losing to fresher curated frontmatter, with the divergence reported. If A6 reddens, this phase broke the thing the epic was for. D1/D2 pin state sync byte-identical. The implementation had to GATE the six guards rather than delete them precisely because state sync has no executor, and a baseline probe showed unconditional deletion drops five fields. Nothing else in the suite would notice that regression. E6 covers #3345's direction — a field preservation restored that the intent never named IS reported. Nothing has ever tested that direction. Assertions were empirically verified against the compiled lib and the real CLI before being written, since the suite cannot be executed locally. That caught two type bugs in the draft: fm.current_phase after a quoted-YAML round-trip is the string '5', not the number 5. E5 is recorded as structurally unreachable rather than weakened or faked. Those four commands report body Title-Case labels, which cannot string-collide with a frontmatter snake_case key the way cmdStatePatch's arbitrary field names can — which is why fix(#3351) targeted only cmdStatePatch. Testing it directly would need reconcileReportedFields exported from private scope; the helper is exercised through E6 and all seven commands instead. * docs(#3471): amend ADR-3408 section 8.5 — a fourth enforcement point, and guards that could not be deleted Amendment 3. The contract held; two of section 8.5's own statements did not. It said the six empty-only guards are DELETED. They cannot be. writeStateMd is the sole path for both section 8.3 sanctioned-permanent exceptions and never runs applyStatePreservation, so those guards were their only empty-field fallback. A baseline probe on the unedited tree confirmed unconditional deletion drops five fields from a blank-body STATE.md on state sync, breaking the byte-identical guarantee section 8.3 grants it. They are gated instead. It also mis-located cmdStateJson's guards, describing them as living in syncStateFrontmatter. They were a separate private copy on the read path with no delta check at all, so a stale body annotation always beat fresher curated frontmatter in state.json — #3395's shape entirely outside the write seam. THE FINDING: a fourth enforcement point nobody had counted. The pre-existing #2202 unknown-key carry-forward loop independently restored the same six fields, silently neutralizing the fix. It is named nowhere in this ADR, in the phase design, or in three prior phases, and was found only because a probe that should have passed did not. Fourth consecutive time a copy count in this epic proved a lower bound: 2 write-seam bypasses became 4, three preservation encodings became four, and the estimate was wrong every time. ADR-3180's standing rule has earned itself in every phase — read the code, not the write-up. Records the Row 2 decision (a discard-to-empty wins per the delta rule and is reported, not silent — the sharpest Hyrum exposure in the epic), section 8.4's residue landing as ONE shared reconcileReportedFields across seven commands rather than five copies, and the parity assertion added because FRONTMATTER_KEY_TO_BODY_LABEL was itself a second table that failed silently — this epic's shape in miniature, in its final phase. * fix(#3471): repair four regressions the checkpoint caught Checkpoint returned 16 failures of 34389: six real regressions in pre-existing tests, plus seven of my own test bugs. My hypothesis was wrong and is recorded as such. I predicted the #2202 carry-forward skip was the cause, reasoning it had removed a load-bearing fallback the way the six guards nearly were. It was not implicated in any of the six. Three unrelated causes: #2111 — current_phase came back undefined from milestone complete, which is the epic's own defect class reintroduced by its final phase. Root cause is Row 2 working exactly as designed: milestoneCompleteCore rewrites the body Phase: line to a closure message, so current_phase's #1230 delta reads CHANGED and the new rule correctly discards the curated value. The transition never declared any intent to touch that field. Fixed by re-asserting current_phase and current_phase_name through authoritativeFm — the existing #2736 mechanism beginPhaseCore and completePhaseCore already use — rather than by weakening Row 2, which A5 pins. That interaction is worth naming: a rule that keys on 'did this write change the body source' will fire on a transition that moves the body line for an entirely unrelated reason. The design did not anticipate it. #1264 / #3242 / the state.patch progress report — reconcileReportedFields folded EVERY divergedFields entry into updated, including preserve-always progress restores no caller asked about. Now scoped to preserve-when-unchanged rows only. #1162 / case-insensitive table fields — valueOf checked frontmatter before body, so a lowercase table field name exact-matched the lowercase frontmatter key sync always derives, comparing stale pre-sync body text against a post-sync frontmatter enum. Flipped to body-first. That last one is the SAME lesson as Phase 2's patchCore, recurring in a different function two phases later: in this model the body is authoritative and frontmatter is the projection, so a name that could mean either resolves body-first. Twice now. Test bugs: a stray unused parameter shifted every argument at six call sites, so body arrived undefined; and A4 compared nested progress scalars against numbers when extractFrontmatter returns raw YAML strings. The string-vs-number YAML round-trip has now been caught three times in this phase alone. * test(#3471): one helper for the progress coercion that bit four times A2f failed on the string-vs-number YAML round-trip: extractFrontmatter returns nested progress scalars as raw YAML strings, so a comparison against numeric literals can never pass. This is the FOURTH time this exact class has been caught in this phase — twice during test authoring, once as A4 in the previous checkpoint, now as A2f. Patching it a fourth time by hand would guarantee a fifth. Added numericProgress() with a comment saying why it exists, and routed every progress-reading assertion in the #3471 block through it. Swept the block: C3 needed no change, because cmdStateJson's output already runs through normalizeProgressNumbers. Deliberately NOT shared with frontmatter.test.cjs's readPersistedProgress: that one is path-based and re-reads from disk, while these assert on an in-memory string that is never written. Sharing would have meant either a disk round-trip these tests do not do, or duplicating half the helper — so the coercion pattern is mirrored locally and the reason recorded, rather than manufacturing a dependency to satisfy the letter of consolidation. * chore(#3471): backfill pr number in changeset fragment --------- Co-authored-by: sim <sim@local>
GSD Core
Git. Ship. Done.
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A light-weight meta-prompting, context engineering, and spec-driven development system for Claude Code, OpenCode, Antigravity CLI, Kimi CLI, Kilo, Codex, Copilot, Cursor, Windsurf, and more.
What is GSD Core
GSD Core is a context-engineering and spec-driven development framework that drives AI coding agents (Claude Code, Codex, Antigravity CLI, Kimi CLI, Copilot, Cursor, and more) through a disciplined phase loop. It solves context rot — the quality degradation that accumulates as an AI fills its context window — by running all heavy research, planning, and execution work in fresh-context subagents while keeping your main session lean.
How it works
Each milestone repeats the same five-step loop, one phase at a time:
- Discuss — capture implementation decisions before anything is planned
- Plan — research, decompose, and verify the plan fits a fresh context window
- Execute — run plans in parallel waves; each executor starts with a clean 200k-token context
- Verify — walk through what was built; diagnose and fix before declaring done
- Ship — create the PR, archive the phase, repeat for the next one
Quickstart
npx @opengsd/gsd-core@latest
The installer prompts for your runtime (Claude Code, OpenCode, Antigravity CLI, Kimi CLI, Kilo, Codex, Copilot, Cursor, Windsurf, and more) and whether to install globally or locally. The installer is required for cross-runtime compatibility — do not copy files from agents/ or commands/ directly.
On another runtime or without Node.js? See Install on your runtime.
Once installed, start a new project or onboard an existing repo:
/gsd-new-project # greenfield project
/gsd-onboard # existing codebase
New here? Follow Your first project for a guided walkthrough from install to first shipped phase, or Onboarding an existing codebase for brownfield setup.
Documentation
What's new in 1.7.0 → docs/whats-new-1.7.0.md
Tutorials — learning by doing:
How-to guides — task-focused recipes:
Reference — authoritative facts:
Explanation — concepts and design decisions:
Full index: docs/README.md. Other languages: 日本語 · 한국어 · Português · 简体中文.
Why it works
Most AI-coding setups fail at scale because context bloat silently degrades output quality, there is no shared memory between sessions, and nothing verifies that code actually works. GSD Core solves all three: heavy work runs in fresh subagents, structured artifacts like STATE.md and CONTEXT.md survive session boundaries, and the verify step walks through what was built and generates fix plans before a phase is declared done. See docs/explanation/context-engineering.md for the full reasoning.
Troubleshooting? See docs/how-to/recover-and-troubleshoot.md.
Community
| Project | Platform |
|---|---|
| gsd-opencode | Original OpenCode port |
| Discord | Community support |
Star History
License
MIT License. See LICENSE for details.
Claude Code is powerful. GSD Core makes it reliable.