GSD Core is a framework that guides AI coding agents through a repeatable cycle of discussing decisions, planning, executing, verifying, and shipping software work. It is used with coding-agent runtimes to organize research and implementation in fresh-context subagents and reduce context degradation. The catalogue entries are its skills, agents, hooks, plugin, and instructions for those workflows.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add open-gsd/gsd-core --skill gsd-reviewgit clone --depth 1 https://github.com/open-gsd/gsd-coreWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/open-gsd/gsd-core/gsd-review)<a href="https://agentmods.dev/skills/open-gsd/gsd-core/gsd-review"><img src="https://agentmods.dev/badge/skills/open-gsd/gsd-core/gsd-review/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/open-gsd/gsd-core/gsd-review"><img src="https://agentmods.dev/badge/skills/open-gsd/gsd-core/gsd-review.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Rogue Agent · line 7 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00018 | $0.00446 |
| Opus 5 | $0.00009 | $0.00223 |
| Sonnet 5 | $0.00004 | $0.00089 |
| Haiku 4.5 | $0.00002 | $0.00045 |
Grade A, and why
gsd-review scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
Copies of this mod
1 near-identical copy found in the catalogue:
- ferrox-review — 89% identical, 8 lines differ
What it actually says
Flow: Detect CLIs → Build review prompt → Invoke each CLI → Collect responses → Write REVIEWS.md
<execution_context> @~/.claude/gsd-core/workflows/review.md </execution_context>
Flags:
--gemini— Include Gemini CLI review--claude— Include Claude CLI review (uses separate session)--codex— Include Codex CLI review--opencode— Include OpenCode review (uses model from user's OpenCode config)--qwen— Include Qwen Code review (Alibaba Qwen models)--cursor— Include Cursor agent review--agy/--antigravity— Include Antigravity CLI review--all— Include all available CLIs
No flags — if review.default_reviewers is set, review with only those configured
reviewers that are detected; otherwise review with all available CLIs. Configured
review.reviewer_instances names may appear in review.default_reviewers; each runs as an
independent reviewer identity backed by its configured adapter+model (see
docs/CONFIGURATION.md). Instance names are not valid as flags.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 6d ago First seen · 49 lines · 18 tokens per session scan A d80db8762bec
gsd-review is a skill published in the GitHub repository open-gsd/gsd-core (9,278 stars, last pushed today), licensed MIT. It adds 18 tokens to every session and 446 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
Other skills, from other repositories
best-practices
Apply modern web development best practices for security, compatibility, and code quality. Use when asked to "apply best practices", "security audit", "modernize code", "code quality review", or "check for vulnerabilities".
review
Review code changes for security, performance, bugs, and quality. Reviews staged changes, unstaged changes, specific commits, or PR-ready diffs.
code-optimizer
Deep code optimization audit using parallel specialist agents that hunt performance anti-patterns via pattern-based detection, avoiding anchoring bias. Covers DB queries, memory leaks, algorithmic complexity, concurrency, bundle size, dead code, I/O/network, rendering, caching, and build config. Use when asked to…
core-web-vitals
Optimize Core Web Vitals (LCP, INP, CLS) for better page experience and search ranking. Use when asked to "improve Core Web Vitals", "fix LCP", "reduce CLS", "optimize INP", "page experience optimization", or "fix layout shifts".
userinterface-wiki
UI/UX best practices for web interfaces. Use when reviewing animations, CSS, audio, typography, UX patterns, prefetching, or icon implementations. Covers 11 categories from animation principles to typography. Outputs file:line findings.
gsd-orchestrator
Build software products autonomously via GSD headless mode. Handles the full lifecycle: write a spec, launch a build, poll for completion, handle blockers, track costs, and verify the result. Use when asked to "build something", "create a project", "run gsd", "check build status", or any task that requires autonomous…