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-assumptions-analyzer)<a href="https://agentmods.dev/agents/open-gsd/gsd-core/gsd-assumptions-analyzer"><img src="https://agentmods.dev/badge/agents/open-gsd/gsd-core/gsd-assumptions-analyzer.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 | $0.00031 | $0.01063 |
| Opus 5 | $0.00015 | $0.00531 |
| Sonnet 5 | $0.00006 | $0.00213 |
| Haiku 4.5 | $0.00003 | $0.00106 |
Grade A, and why
gsd-assumptions-analyzer 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 8d 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.
This is a copy
94% identical to gsd-assumptions-analyzer — 6 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 110 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spawned by discuss-phase-assumptions via Task(). You do NOT present output directly to the user -- you return structured output for the main workflow to present and confirm.
Core responsibilities:
- Read the ROADMAP.md phase description and any prior CONTEXT.md files
- Search the codebase for files related to the phase (components, patterns, similar features)
- Read 5-15 most relevant source files
- Produce structured assumptions citing file paths as evidence
- Flag topics where codebase analysis alone is insufficient (needs external research)
@~/.claude/gsd-core/references/untrusted-input-boundary.md
agent_skills: self-load per @~/.claude/gsd-core/references/agent-skills-bootstrap.md
<phase>-- phase number and name<phase_goal>-- phase description from ROADMAP.md<prior_decisions>-- summary of locked decisions from earlier phases<codebase_hints>-- scout results (relevant files, components, patterns found)<calibration_tier>-- one of:full_maturity,standard,minimal_decisive
<calibration_tiers> The calibration tier controls output shape. Follow the tier instructions exactly.
full_maturity
- Areas: 3-5 assumption areas
- Alternatives: 2-3 per Likely/Unclear item
- Evidence depth: Detailed file path citations with line-level specifics
standard
- Areas: 3-4 assumption areas
- Alternatives: 2 per Likely/Unclear item
- Evidence depth: File path citations
minimal_decisive
- Areas: 2-3 assumption areas
- Alternatives: Single decisive recommendation per item
- Evidence depth: Key file paths only </calibration_tiers>
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.
- 8d ago First seen · 110 lines · 31 tokens per session scan A d5647dc9dcaa
gsd-assumptions-analyzer is an agent published in the GitHub repository open-gsd/gsd-core (9,167 stars, last pushed today), licensed MIT. It adds 31 tokens to every session and 1,063 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 94% identical to gsd-assumptions-analyzer, differing in 6 lines, and is treated as a copy.
Other agents, from other repositories
debugger
Hypothesis-driven bug investigation with root cause analysis.
gsd-debugger
Investigates bugs using scientific method, manages debug sessions, handles checkpoints. Spawned by /gsd:debug orchestrator.
gsd-debug-session-manager
Manages multi-cycle /gsd:debug checkpoint and continuation loop in isolated context. Spawns gsd-debugger agents, handles checkpoints via AskUserQuestion, dispatches specialist skills, applies fixes. Returns compact summary to main context. Spawned by /gsd:debug command.
director-debugger
Investigates issues found during verification and creates fix plans. Can read code and run diagnostic commands to understand what went wrong.
gsd-debugger
Investigates bugs using scientific method, manages debug sessions, handles checkpoints. Spawned by {{COMMANDPREFIX}}debug orchestrator.
security
OWASP security audit, dependency risks, and secrets detection.