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 Liberty91LTD/cti-skills --skill achgit clone --depth 1 https://github.com/Liberty91LTD/cti-skillsWrote 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/liberty91ltd/cti-skills/ach)<a href="https://agentmods.dev/skills/liberty91ltd/cti-skills/ach"><img src="https://agentmods.dev/badge/skills/liberty91ltd/cti-skills/ach/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/liberty91ltd/cti-skills/ach"><img src="https://agentmods.dev/badge/skills/liberty91ltd/cti-skills/ach.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 | $0.00073 | $0.03616 |
| Opus 5.5 | $0.00029 | $0.01446 |
| Sonnet 5.5 | $0.00015 | $0.00723 |
| Haiku 4.5 | $0.00007 | $0.00362 |
Grade A, and why
ach 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 — 232 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Analysis of Competing Hypotheses (ACH)
ACH is the most important structured analytic technique for CTI. It forces you to evaluate ALL plausible hypotheses against ALL significant evidence, reducing the impact of cognitive biases — especially confirmation bias.
When to Use ACH
- Attribution questions: "Who is behind this campaign?"
- Ambiguous situations: Multiple plausible explanations exist
- High-stakes assessments: Getting it wrong has significant consequences
- Contested analysis: Analysts disagree on the conclusion
Evidence: Graded Preferred, Ungraded Allowed
ACH works best on graded evidence items, one per claim, as produced by /quality-of-information-check (the QoI JSON or its claim table). The schema is in skills/quality-of-information-check/references/evidence-item-schema.md. Grading is the default. It is not a condition for running.
An item counts as graded when it has all of: claim_id, claim, claim_type, anchor, grading.access_level, grading.claim_support, corroboration and provenance_basis.
| What you were handed | What to do |
|---|---|
| QoI JSON or graded claim table | Proceed. If the JSON is a file, confirm it with python3 skills/quality-of-information-check/scripts/validate_evidence.py <qoi.json> (exit 0 = valid). Items that fail are not graded evidence: rerun the check on them or carry them as ungraded. |
| Raw URLs, articles, pasted report text | Complete Step 1, then invoke /quality-of-information-check on the material, passing the question. Use its output as the evidence. This is the default and needs no permission. |
| Evidence with a bare source rating but no claim table (for example "Mandiant report, Admiralty B2") | Run /quality-of-information-check on the underlying document if it is available. If not, carry the item as ungraded and record the rating as the analyst's own. |
| Evidence the user asserts from memory, with no document behind it | Cannot be graded. Carry it as ungraded, marked "asserted, no document". |
| A mix of graded and ungraded | Grade what can be graded. Carry the rest as ungraded. Graded rows keep their grades and weights. |
The user asks to skip grading, or /quality-of-information-check cannot be run |
Run in ungraded mode, below. Say once what that costs, then proceed. Do not ask again. |
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 Changed · +110 lines · +44 tokens per session 998025ba4c99
- 2mo ago First seen · 122 lines · 29 tokens per session scan A e7388b69849d
ach is a skill published in the GitHub repository Liberty91LTD/cti-skills (36 stars, last pushed 4d ago), licensed MIT. It adds 73 tokens to every session and 3,616 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 2026-08-30.
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