microsoft/cat-agent-skills is a static website that catalogs reusable instruction sets and related packages for AI agents. People use it to search, filter, rate, and download skills for Cowork, Copilot Studio, and Scout, along with Copilot plugins and Scout automations. The catalogue entries are the skills, instructions, plugins, and settings displayed by the site.
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 microsoft/cat-agent-skills --skill failure-mode-rankgit clone --depth 1 https://github.com/microsoft/cat-agent-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/microsoft/cat-agent-skills/failure-mode-rank)<a href="https://agentmods.dev/skills/microsoft/cat-agent-skills/failure-mode-rank"><img src="https://agentmods.dev/badge/skills/microsoft/cat-agent-skills/failure-mode-rank/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/microsoft/cat-agent-skills/failure-mode-rank"><img src="https://agentmods.dev/badge/skills/microsoft/cat-agent-skills/failure-mode-rank.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 | $0.00071 | $0.00524 |
| Opus 5.5 | $0.00028 | $0.00210 |
| Sonnet 5.5 | $0.00014 | $0.00105 |
| Haiku 4.5 | $0.00007 | $0.00052 |
Grade A, and why
failure-mode-rank 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 today.
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
Failure-Mode Rank
Purpose
Deterministically rank the candidate failure modes for the fault, matching symptoms and alarm codes to the failure-mode library and applying the repeat-failure root-cause promotion rule.
When to use
- After history-retrieve, in every triage run.
- "What's the likely cause?" / "rank the failure modes" / "is the reset masking something?".
Inputs
- The contract payload with
symptoms[],alarm_codes[], andhistory{}(contractmfg.maintenance-triage.v1).
Steps
- Validate the payload against the contract.
- Run
scripts/fault_rank.py --intake fault-intake.json --out ranked-causes.json. - Do not restate or recompute any score in prose; quote the engine output verbatim.
- Emit the
{ranked_causes}contract payload.
Output
Contract mfg.maintenance-triage.v1 with populated ranked_causes[] (rank, failure_mode,
match_score, evidence, recommended_fix, confidence, source=engine:fault_rank, citation) and
history.repeat_promotion — the {ranked_causes} hop.
Grounding requirements
Every ranked cause carries its OEM manual / library citation; the promotion of a root cause
over a symptomatic fix cites references/failure-mode-library.md #3.1.
Constraints
- All ranking math happens in the engine. The model must never re-rank causes itself.
- No priority or cost talk here — that is criticality-rank's job.
- Never suppress the repeat-failure promotion because a cheaper symptomatic fix "usually works".
Escalation / uncertainty
- Top candidate confidence below the 0.75 floor, or two candidates within the ambiguity
band: the engine adds to
escalations[]; surface it and route to a human diagnosis (failure-mode-library.md #4.1-#4.2).
What ships with it
7 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.
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.
- today First seen · 50 lines · 71 tokens per session scan A 9455c09c9c53
failure-mode-rank is a skill published in the GitHub repository microsoft/cat-agent-skills (93 stars, last pushed today), licensed MIT. It adds 71 tokens to every session and 524 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 2026-10-28.
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