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 agentmods add skills/open-gsd/gsd-core/gsd-surfacenpx skills add open-gsd/gsd-core --skill gsd-surfacegit 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-surface)<a href="https://agentmods.dev/skills/open-gsd/gsd-core/gsd-surface"><img src="https://agentmods.dev/badge/skills/open-gsd/gsd-core/gsd-surface.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00023 | $0.01445 |
| Opus 5 | $0.00012 | $0.00723 |
| Sonnet 5 | $0.00005 | $0.00289 |
| Haiku 4.5 | $0.00002 | $0.00145 |
Grade A, and why
gsd-surface 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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 163 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Sub-commands: list · status · profile · disable · enable · reset
Sub-command routing
Parse the first token of $ARGUMENTS:
| Token | Action |
|---|---|
list |
Show enabled + disabled clusters and skills |
status |
Alias for list plus token cost summary |
profile <name> |
Write baseProfile and re-stage |
profile <n1>,<n2> |
Composed profiles (comma-separated, no spaces) |
disable <cluster> |
Add cluster to disabledClusters, re-stage |
enable <cluster> |
Remove cluster from disabledClusters, re-stage |
reset |
Delete .gsd-surface.json, return to install-time profile |
| (none) | Treat as list |
list / status
Load the capability registry and call listSurface(runtimeConfigDir, manifest, CLUSTERS, registry) from
the engine module at ${runtimeConfigDir}/gsd-core/bin/lib/surface.cjs. The registry is loaded via:
const registry = require(runtimeConfigDir + '/gsd-core/bin/lib/capability-registry.cjs');
Display:
Enabled (N skills, ~T tokens):
core_loop: new-project discuss-phase plan-phase execute-phase help update
audit_review: …
…
Disabled:
utility: health stats settings …
Token cost: ~T (budget cap ~500 tokens for 200k context @ 1%)
For status also append:
Base profile: standard (from .gsd-surface.json)
Install profile: standard (from .gsd-profile)
profile <name>
- Read current surface:
readSurface(runtimeConfigDir)→ if null, seed fromreadActiveProfile(runtimeConfigDir). - Set
surfaceState.baseProfile = name. writeSurface(runtimeConfigDir, surfaceState).- Resolve and re-apply:
const registry = require(runtimeConfigDir + '/gsd-core/bin/lib/capability-registry.cjs'); const layout = resolveRuntimeArtifactLayout(runtime, runtimeConfigDir, scope); applySurface(runtimeConfigDir, layout, manifest, CLUSTERS, registry); - Confirm: "Surface updated to profile
<name>. N skills enabled."
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.
- 2d ago First seen · 163 lines · 23 tokens per session scan A cf3c08a3fe96
gsd-surface is a skill published in the GitHub repository open-gsd/gsd-core (9,125 stars, last pushed today), licensed MIT. It adds 23 tokens to every session and 1,445 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
btw
Ask a quick side question about your current work without derailing the main task. Answers from existing conversation context only — no tool calls, no file reads, single concise response. Use when you need a fast answer from what is already in this session.
director:help
Show Director commands with examples. Use when the user asks what Director can do, how to use it, or needs guidance.
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".
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…