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 Dankosik/go-service-template-rest --skill go-domain-invariantgit clone --depth 1 https://github.com/Dankosik/go-service-template-restWrote 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/dankosik/go-service-template-rest/go-domain-invariant)<a href="https://agentmods.dev/skills/dankosik/go-service-template-rest/go-domain-invariant"><img src="https://agentmods.dev/badge/skills/dankosik/go-service-template-rest/go-domain-invariant/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/dankosik/go-service-template-rest/go-domain-invariant"><img src="https://agentmods.dev/badge/skills/dankosik/go-service-template-rest/go-domain-invariant.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 | $0.00032 | $0.00374 |
| Opus 5 | $0.00016 | $0.00187 |
| Sonnet 5 | $0.00006 | $0.00075 |
| Haiku 4.5 | $0.00003 | $0.00037 |
Grade A, and why
go-domain-invariant 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 4d 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.
What it actually says
Go Domain Invariant
A business rule is an invariant: a statement about state and transitions that stays true under every accepting path, replay, and version mix — or it is a wish, not a rule.
accepted terms -> states and transitions -> acceptance conditions -> rejection surfaces -> effect order -> replay -> proof
State each invariant in accepted business terms with the input, sequence, or replay that falsifies it and the surface that rejects the attempt. The domain owns effect order, duplicate meaning, and out-of-order meaning.
For a delegated Decision or Review, or when the active artifact requires its
result interface, load the
shared specialist contract.
From every changed accepting path through its false case and replay, build
InvariantRecord{rule, owner, accepting_paths, transitions, false_case, rejection, effect_order, replay, mixed_version, proof}. A rule is incomplete
until every accepting path and invalid move has a disposition.
Choose The Branch
- Decision — load one matching decision reference and cover every invariant and transition with rejection, effect boundary, forced consequence, and proof obligation.
- Review — load one matching review reference and follow every affected accepting path into the finding envelope with falsifying proof.
Complete when every invariant is falsifiable in accepted business terms, every invalid move has one deterministic rejection surface, and proof would fail if an alternate accepting path bypassed the rule.
What ships with it
10 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/decision/idempotency-replay-and-async-domain-rules.md 2.3 KB
- references/decision/index.md 1.6 KB
- references/decision/invariant-register-patterns.md 2.3 KB
- references/decision/invariant-violation-semantics.md 1.9 KB
- references/decision/state-machine-and-transition-rules.md 1.7 KB
- references/review/acceptance-and-rejection-semantics.md 2.0 KB
- references/review/domain-test-traceability.md 1.6 KB
- references/review/effect-escape-and-duplication-review.md 2.4 KB
- references/review/index.md 1.4 KB
- references/review/invalid-state-and-transition-review.md 1.9 KB
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.
- 4d ago Changed · +2 lines ad1a0d83e171
- 12d ago First seen · 37 lines · 32 tokens per session scan A cfe0b7a213d8
go-domain-invariant is a skill published in the GitHub repository Dankosik/go-service-template-rest (7 stars, last pushed 4d ago), licensed MIT. It adds 32 tokens to every session and 374 once invoked, about $0.0002 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 2026-08-31.
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