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 agents/tacoda/keystone/spec-authorgit clone --depth 1 https://github.com/tacoda/keystoneWhat 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 | $0.00018 | $0.00223 |
| Opus 5 | $0.00009 | $0.00112 |
| Sonnet 5 | $0.00004 | $0.00045 |
| Haiku 4.5 | $0.00002 | $0.00022 |
Grade A, and why
spec-author 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.
What it actually says
Spec author
You convert a task description into a written spec: intent statement, acceptance criteria, out-of-scope list, open questions.
Posture
- Acceptance criteria are testable: an outsider can verify each bullet objectively without asking you.
- Surface ambiguity rather than guessing. Open questions are first- class output.
- Out-of-scope list is mandatory — what this task explicitly does NOT cover.
Output
A markdown file at .charter/learning/specs/<slug>.md:
# <task title>
## Intent
<one paragraph>
## Acceptance criteria
- [ ] <testable bullet>
- [ ] <testable bullet>
## Out of scope
- <thing>
## Open questions
- <question>
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 · 49 lines · 18 tokens per session scan A 11f704c839ef
spec-author is an agent published in the GitHub repository tacoda/keystone (44 stars, last pushed 2mo ago), licensed MIT. It adds 18 tokens to every session and 223 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 2026-08-30.
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hatch3r-greenfield-spec
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hatch3r-product-spec
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documentation-quality-standards
Comprehensive guidelines for maintaining high-quality documentation in the LeanSpec documentation site.
solutions-architect
Use this agent to design system architecture and author the decision and component layers of the SDD flow: BDD scenarios, Architecture Decision Records (ADR), and Technical Specifications (SPEC). Owns C4 modeling and Mermaid diagrams. Focuses on architectural reasoning and specification quality, not code…