* test(#1963): add failing-first prevention/postmortem contract tests Epic #1957 Phase 3B. Source-text-is-the-product contract tests: blameless 5-Whys that BRANCHES per Phase 2A RCA (not a single-cause chain; treats agent error as 'why was that possible?'), the 'why wasn't this caught?' question, the recurrence-guard taxonomy (regression test / assertion / lint rule / KB pattern), the KB-entry why_not_caught + recurrence_guard fields with backward compat, the session-manager prevention summary line, and the Zawinski scope-boundary (a block, not a subsystem). Failing-first: reference, archive_session edit, KB schema extension, and session-manager summary do not yet exist. * feat(#1963): emit blameless-postmortem Prevention block at resolution Epic #1957 Phase 3B. At archive_session the debugger now produces a Prevention block with three blame-free components: a branching 5-Whys causal chain (branches per Phase 2A RCA, not a single chain; 'agent error' prompts 'why was that possible?', never blame), a 'why wasn't this caught?' answer naming the missed gate (test/typecheck/lint/review/verify), and a concrete recurrence guard (regression test / assertion / lint rule / KB pattern). The knowledge-base entry gains two structured fields (why_not_caught + recurrence_guard) so future Phase-0 recall surfaces the prior prevention, not just the prior fix. Additive: old entries without the fields still load. The session-manager compact summary surfaces a one-line prevention summary. Full rules extracted to gsd-core/references/debugger-prevention.md (slim archive_session step + 2 KB fields kept in the agent). INVENTORY + manifest + agent-size baseline + install-parity goldens + AGENTS.md updated. * fix(#1963): address orthogonal review (CRITICAL append-template drift + Phase-0 consumption + parity test) - CRITICAL: the archive_session KB append template omitted Why not caught + Recurrence guard (only the Entry Format had them) — the feature's core deliverable silently did not happen. Added both fields to the append template the agent actually follows (nearest-instruction wins). - HIGH: Phase 0 (KB read) only surfaced root_cause + fix; the new fields were dead data. Extended the Phase 0 Evidence line to consume why_not_caught + recurrence_guard when present (absent on old entries — backward compat holds). - MEDIUM: added a cross-section parity test (every Entry-Format field must also appear in the append template — the guard that would have caught the Critical) + a Phase-0-consumption assertion. - MEDIUM: the 'branches per Phase 2A' claim is now wired — reuses reasoning_checkpoint.candidate_causes across the four categories. - MEDIUM: recurrence-guard taxonomy gains type refinement + config-default change; LOW: added 'build' gate to both surfaces for parity. - NIT: compact-summary fallback shape ('no gate existed'); verify the guard artifact exists before recording it. * test(#1963): anchor Phase-0 consumption test on the specific heading The regex /Phase 0[\s\S]{0,1200}/ matched the first 'Phase 0' in the file (in knowledge_base_protocol prose), not the Phase 0 block in investigation_loop. Anchor on '**Phase 0: Check knowledge base**' and widen to 1500 chars. * chore(#1963): backfill changeset pr number (PR #2410)
GSD Core
Git. Ship. Done.
English · Português · 简体中文 · 日本語 · 한국어
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.