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 skills/simota/agent-skills/chainnpx skills add simota/agent-skills --skill chaingit clone --depth 1 https://github.com/simota/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/simota/agent-skills/chain)<a href="https://agentmods.dev/skills/simota/agent-skills/chain"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/chain.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 | $0.00043 | $0.05631 |
| Opus 5 | $0.00022 | $0.02815 |
| Sonnet 5 | $0.00009 | $0.01126 |
| Haiku 4.5 | $0.00004 | $0.00563 |
Grade E, and why
chain scanned grade E with 5 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.
Hidden instructionshighPrompt injection
Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.
<!-- CAPABILITIES_SUMMARY: - skill_intake_audit: Run the third-party skill intake checklist (`_common/SECURITY.md`) against an unaudited skill directory - manifest_generation: Produce and verify `.chain-manifest.json` (s Reaches for credential filesmediumPrivilege escalation
SSH keys, cloud credentials, git-credentials, .npmrc, /etc/shadow: reading these is how a config file becomes a credential leak.
- Scan every bundled `.sh`, `.py`, `.js`, `.ts` file for `curl ... | bash`, `wget ... | sh`, `eval $(...)`, `base64 -d | sh`, network exfil to non-allowlisted hosts, and credential-path reads (`~/.ssh`, `~/.aws`, `~/.con Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.
Downloads and executes remote codemediumSupply chain
curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.
- a Unicode anomaly or `curl ... | bash` pattern is suspected inside any agent-loaded file Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.
Encoded or obfuscated payloadmediumSupply chain
base64 or hex that is decoded and executed hides what actually runs from anyone reading the file.
- Scan every bundled `.sh`, `.py`, `.js`, `.ts` file for `curl ... | bash`, `wget ... | sh`, `eval $(...)`, `base64 -d | sh`, network exfil to non-allowlisted hosts, and credential-path reads (`~/.ssh`, `~/.aws`, `~/.con Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
- a Unicode anomaly or `curl ... | bash` pattern is suspected inside any agent-loaded file How it starts
The opening of the file, as written. The whole thing — 290 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Chain
"Treat every third-party skill like an npm install. Audit before invoking."
Supply-chain trust and compromise specialist. Chain audits skill/plugin/MCP intake and also investigates package-ecosystem compromise in developer machines, CI runners, and container images using source-cited IoCs, evidence-preserving eradication, and rotation gates.
Principles: Default-distrust · Manifest-first · No-invisible-chars · Pin-MCP-tools · Escalate-not-execute · Frontmatter-stays-minimal
What ships with it
14 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.
- _common 10 B
- reference/_common 13 B
- reference/audit-decision-matrix.md 1.9 KB
- reference/autorun-schema.md 1.8 KB
- reference/bundled-artifact-review.md 8.4 KB
- reference/chain 11 B
- reference/intake-checklist.md 12 KB
- reference/recipes-index.md 2.2 KB
- reference/reference-index.md 1.8 KB
- reference/supply-chain-malware-eradication.md 14 KB
- reference/supply-chain-malware-handoffs.md 5.8 KB
- reference/supply-chain-malware-ioc-database.md 15 KB
- reference/supply-chain-malware-scan-procedures.md 12 KB
- reference/unicode-tag-scan.md 6.7 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 First seen · 290 lines · 43 tokens per session scan E 65f02a46a22f
chain is a skill published in the GitHub repository simota/agent-skills (75 stars, last pushed yesterday), licensed MIT. It adds 43 tokens to every session and 5,631 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it E with 5 findings (hidden instructions, reaches for credential files, downloads and executes remote code). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
assimilate-popular-workflows
This skill should be used when the user asks to "find skills in the wild", "assimilate popular workflows", "discover SKILL.md files in repos", "research external skills", "find workflow patterns", "survey the skill landscape", "what skills exist out there", or wants to investigate public repositories for extractable…
stage-plan
How to turn "here is my material + here's the video I want" into a single, inspectable plan that spans reference images, reference videos, deterministic editing, semantic editing, generation, and composition. The output is project/plan.json — a cross-modal Edit Decision List (EDL) — which the assembler walks.…
design-system-importer
Use this when COMPOSE or an AUTO compose segment has any external reference media or style source: a reference image, reference video, DESIGN.md, brand guide, screenshot, existing website, design notes, or an explicit named visual direction.
ui-design-source
Use this skill when the user provides Figma material, design-export files, screenshots of design tools, PDFs, JSON, existing HTML, or asks for design-to-HTML/code fidelity. It adapts OpenDesign/Figma handoff discipline for UIDesigner without requiring a live Figma runtime.
seo-crawl
Agent-wide core connector rule: when any connected search console is used, discover its operations with listconnectortools and invoke each selected operation through callconnectortool; naming listsites or an analytics operation without the core invocation is not execution.
swiftui-dev
Use this skill for SwiftUI development, architecture, structure, performance, and Apple native app profiling. It combines.