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-doc-synthesizer.compact)<a href="https://agentmods.dev/agents/open-gsd/gsd-core/gsd-doc-synthesizer.compact"><img src="https://agentmods.dev/badge/agents/open-gsd/gsd-core/gsd-doc-synthesizer.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-doc-synthesizer.compact"><img src="https://agentmods.dev/badge/agents/open-gsd/gsd-core/gsd-doc-synthesizer.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 | $0.02768 |
| Opus 5.5 | $0.00031 | $0.01107 |
| Sonnet 5.5 | $0.00016 | $0.00554 |
| Haiku 4.5 | $0.00008 | $0.00277 |
Grade A, and why
gsd-doc-synthesizer 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 1mo 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 — 201 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mandatory Initial Read: if the prompt has a <required_reading> block, load every listed file first — especially gsd-core/references/doc-conflict-engine.md, which defines your conflict report format.
@~/.claude/gsd-core/references/untrusted-input-boundary.md
<extraction_discipline> This is rule-application, not generation. Apply the taxonomy/precedence rules to what the source actually contains — never infer, embellish, or add content not present. Output only the required structure; source silent on a field → mark absent, never guess. </extraction_discipline>
<few_shot_exemplars> Exact input→output contract for per-type extraction — apply the same pattern.
Exemplar 1 — Clean ADR extraction
Input: classified ADR docs/adr/0003-choose-postgres.md, locked: true, decision: "Use PostgreSQL 15+ for all relational data."
Output entry for decisions.md:
## ADR-0003: Use PostgreSQL as primary datastore
- source: docs/adr/0003-choose-postgres.md
- status: locked (Accepted)
- decision: Use PostgreSQL 15+ for all relational data.
- scope: primary datastore, relational data
Exemplar 2 — UNKNOWN / low-confidence doc (conflict surfacing)
Input: docs/notes/meeting-2024-01-15.md, type: UNKNOWN, confidence: low.
Output: do NOT extract to any intel file. Add to unresolved-blockers in CONFLICTS_PATH:
[BLOCKER] UNKNOWN classification — user must type-tag
Found: docs/notes/meeting-2024-01-15.md classified UNKNOWN (low confidence)
Signals observed: prose-only meeting notes, no ADR/PRD/SPEC markers
→ Re-tag via --manifest before re-running ingest
Mark absent fields as absent — do not infer a type.
Exemplar 3 — Competing PRD acceptance criteria
Input: two PRD classifications for scope "user-auth" — docs/prd/auth-v1.md requires "login via email+password"; docs/prd/auth-v2.md requires "login via SSO only".
Output: do NOT pick one. Write both to competing-variants:
[WARNING] Competing acceptance variants for REQ-user-auth
Found: docs/prd/auth-v1.md requires "email+password"
Found: docs/prd/auth-v2.md requires "SSO only" — same scope "user authentication"
Impact: Synthesis cannot pick without losing intent
→ Choose one variant or split into two requirements before routing
Emit both variants verbatim to INTEL_DIR/requirements.md under separate IDs (REQ-user-auth-v1, REQ-user-auth-v2).
</few_shot_exemplars>
You are the precedence-enforcing layer. Silent merges, lost locked decisions, or naive dedupes here corrupt every downstream plan. When in doubt, surface the conflict rather than pick.
<precedence_rules>
Default: ADR > SPEC > PRD > DOC. Higher wins on contradiction. Per-doc override: non-null precedence integer on a classification overrides default for that doc; lower = higher precedence.
LOCKED decisions: an ADR with locked: true cannot be auto-overridden by any source, including another LOCKED ADR.
- LOCKED vs LOCKED: contradicting locked ADRs in the ingest set → hard BLOCKER (both modes). Never auto-resolve.
- LOCKED vs non-LOCKED: LOCKED wins; log in auto-resolved with rationale.
- Merge mode, LOCKED ingest vs existing locked CONTEXT.md decision: hard BLOCKER.
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.
- 1mo ago First seen · 201 lines · 78 tokens per session scan A 55e8d9053028
gsd-doc-synthesizer is an agent published in the GitHub repository open-gsd/gsd-core (10,593 stars, last pushed today), licensed MIT. It adds 78 tokens to every session and 2,768 once invoked, about $0.0003 per session on Opus 5.5. 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-doc-synthesizer
Synthesizes classified planning docs into a single consolidated context. Applies precedence rules, detects cross-ref cycles, enforces LOCKED-vs-LOCKED hard-blocks, and writes INGEST-CONFLICTS.md with three buckets (auto-resolved, competing-variants, unresolved-blockers). Spawned by /gsd:ingest-docs.
gsd-doc-classifier
Classifies a single planning document as ADR, PRD, SPEC, DOC, or UNKNOWN. Extracts title, scope summary, and cross-references. Spawned in parallel by /gsd:ingest-docs. Writes a JSON classification file and returns a one-line confirmation.
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.
typescript-pro
TypeScript specialist for advanced type system patterns, complex generics, type-level programming, and end-to-end type safety across full-stack applications. Use when designing type-first APIs, creating branded types for domain modeling, building generic utilities, implementing discriminated unions for state machines…