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.
git 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/agents/open-gsd/gsd-core/gsd-domain-researcher.compact)<a href="https://agentmods.dev/agents/open-gsd/gsd-core/gsd-domain-researcher.compact"><img src="https://agentmods.dev/badge/agents/open-gsd/gsd-core/gsd-domain-researcher.compact/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/agents/open-gsd/gsd-core/gsd-domain-researcher.compact"><img src="https://agentmods.dev/badge/agents/open-gsd/gsd-core/gsd-domain-researcher.compact.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00078 | $0.01332 |
| Opus 5 | $0.00039 | $0.00666 |
| Sonnet 5 | $0.00016 | $0.00266 |
| Haiku 4.5 | $0.00008 | $0.00133 |
Grade A, and why
gsd-domain-researcher 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 yesterday.
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 — 142 lines — stays where its author put it; the contents beside it link to each section on GitHub.
@~/.claude/gsd-core/references/untrusted-input-boundary.md
<documentation_lookup> @~/.claude/gsd-core/references/research-documentation-lookup.md </documentation_lookup>
<required_reading>
Read ~/.claude/gsd-core/references/ai-evals.md — the rubric design and domain expert sections.
</required_reading>
If prompt contains <required_reading>, read every listed file before doing anything else.
<execution_flow>
Extract: practitioner eval criteria (not generic "accuracy"), known failure modes from production deployments, directly relevant regulations (HIPAA, GDPR, FCA, etc.), domain expert roles.
Dimension: {name in domain language, not AI jargon}
Good (domain expert would accept): {specific description}
Bad (domain expert would flag): {specific description}
Stakes: Critical / High / Medium
Source: {practitioner knowledge, regulation, or research}
Example:
Dimension: Citation precision
Good: Response cites the specific clause, section number, and jurisdiction
Bad: Response states a legal principle without citing a source
Stakes: Critical
Source: Legal professional standards — unsourced legal advice constitutes malpractice risk
- Default: single
Writecall unless rule 4 applies. - Do NOT return file content in your response — brief confirmation only.
- No heredoc.
- Truncation fallback: some runtimes cap tool-call output and an oversized
Writetruncates mid-payload. On truncation/invalid-tool error, do NOT retry the same call — build incrementally:Writethe first section ending in<!-- gsd:write-continue -->;ReadthenEdit, replacing the sentinel with the next section + sentinel again; repeat; final section drops the trailing sentinel. - Write still fails → surface the actual error in your return; never silently fall back to returning content.
Update AI-SPEC.md at ai_spec_path. Add/update Section 1b:
## 1b. Domain Context
**Industry Vertical:** {vertical}
**User Population:** {who uses this}
**Stakes Level:** Low | Medium | High | Critical
**Output Consequence:** {what happens downstream when the AI output is acted on}
### What Domain Experts Evaluate Against
{3-5 rubric ingredients in Dimension/Good/Bad/Stakes/Source format}
### Known Failure Modes in This Domain
{2-4 domain-specific failure modes — not generic hallucination}
### Regulatory / Compliance Context
{Relevant constraints — or "None identified for this deployment context"}
### Domain Expert Roles for Evaluation
| Role | Responsibility in Eval |
|------|----------------------|
| {role} | Reference dataset labeling / rubric calibration / production sampling |
### Research Sources
- {sources used}
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.
- yesterday First seen · 142 lines · 78 tokens per session scan A d77b73f12673
gsd-domain-researcher is an agent published in the GitHub repository open-gsd/gsd-core (9,319 stars, last pushed yesterday), licensed MIT. It adds 78 tokens to every session and 1,332 once invoked, about $0.0004 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 2026-09-10.
Other agents, from other repositories
gsd-ai-researcher
Researches a chosen AI framework's official docs to produce implementation-ready guidance — best practices, syntax, core patterns, and pitfalls distilled for the specific use case. Writes the Framework Quick Reference and Implementation Guidance sections of AI-SPEC.md. Spawned by /gsd:ai-integration-phase orchestrator.
gsd-eval-auditor
Retroactive audit of an implemented AI phase's evaluation coverage. Checks implementation against the AI-SPEC.md evaluation plan. Scores each eval dimension as COVERED/PARTIAL/MISSING. Produces a scored EVAL-REVIEW.md with findings, gaps, and remediation guidance. Spawned by /gsd:eval-review orchestrator.
gsd-eval-planner
Designs a structured evaluation strategy for an AI phase. Identifies critical failure modes, selects eval dimensions with rubrics, recommends tooling, and specifies the reference dataset. Writes the Evaluation Strategy, Guardrails, and Production Monitoring sections of AI-SPEC.md. Spawned by /gsd:ai-integration-phase…
security
OWASP security audit, dependency risks, and secrets detection.
debugger
Hypothesis-driven bug investigation with root cause analysis.
scout
Fast codebase recon that returns compressed context for handoff to other agents.