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/kouroshez/coding-os/linux-sysadminnpx skills add kouroshez/coding-os --skill linux-sysadmingit clone --depth 1 https://github.com/kouroshez/coding-osWhat 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 | $0.00171 | $0.01550 |
| Opus 5 | $0.00086 | $0.00775 |
| Sonnet 5 | $0.00034 | $0.00310 |
| Haiku 4.5 | $0.00017 | $0.00155 |
Grade B, and why
linux-sysadmin scanned grade B with 3 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 yesterday.
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.
Asks for rootlowPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
- `curl … | sudo bash` from an unverified source → read it first. 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.
- `curl … | sudo bash` from an unverified source → read it first. 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.
- `curl … | sudo bash` from an unverified source → read it first. How it starts
The opening of the file, as written. The whole thing — 116 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Linux System Administration
A server is a contract with production: it stays up, it's reachable only how you intend, and when it misbehaves you can see why in one pass. This skill is host-level operation + hardening. Containers and pipelines belong to deployment-cicd; the incident process to incident-response; this is the box itself.
Triage a host in one compact report (disk, mem, load, failed units, ports):
bash scripts/triage.sh --json
SSH — the front door, hardened
# /etc/ssh/sshd_config.d/10-hardening.conf (drop-in, survives package upgrades)
PermitRootLogin no
PasswordAuthentication no # keys only — the single biggest win
PubkeyAuthentication yes
KbdInteractiveAuthentication no
MaxAuthTries 3
AllowUsers deploy # allow-list, not everyone
# Wrong — edits the main file, lost on upgrade, no syntax check before reload
vi /etc/ssh/sshd_config && systemctl restart sshd # locks you out if typo'd
# Correct — drop-in + validate + reload (keeps your current session alive)
sshd -t && systemctl reload sshd # -t aborts on bad config
Keys not passwords, root login off, an AllowUsers allow-list, fail2ban for brute-force. Never restart sshd before sshd -t passes — a typo + restart locks you out of a remote box. Full hardening → references/ssh-hardening.md.
systemd — services that restart themselves
# /etc/systemd/system/api.service
[Unit]
Description=API service
After=network-online.target
[Service]
ExecStart=/usr/local/bin/api --port 8080
Restart=on-failure
RestartSec=2
User=api # never run a service as root
NoNewPrivileges=true # cheap hardening
ProtectSystem=strict # read-only /usr, /boot, /etc
[Install]
WantedBy=multi-user.target
systemctl daemon-reload after editing a unit, then enable --now. Read failures with systemctl status api + journalctl -u api -e --no-pager. A service with no Restart= dies silently on the first crash. Recipes → references/systemd-and-services.md.
What ships with it
5 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.
- yesterday First seen · 116 lines · 171 tokens per session scan B 33c637b3c09c
linux-sysadmin is a skill published in the GitHub repository kouroshez/coding-os (6 stars, last pushed yesterday), licensed Apache-2.0. It adds 171 tokens to every session and 1,550 once invoked, about $0.0009 per session on Opus 5. A static security scan graded it B with 3 findings (asks for root, downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
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potpie-infra-architecture
Use for project infra and architecture context: environments, adapters, runtime configuration, deployments, service dependencies, datastores, API contracts, ownership, incidents, and dependency blast radius.
wiki-context-pack
Produce a token-bounded, citation-ready context slice from an existing Obsidian vault for a downstream agent or task. Use for "/wiki-context-pack", "use my vault as context", "context slice for X", "pack the wiki for my agent", or "bounded context for Y".
alfworld-receptacle-finder
Searches for a suitable empty or appropriately occupied receptacle (like a shelf or table) to place an object. Use when you are holding an object that needs to be stored or placed and must find a receptacle that meets the placement criteria. Examines candidate receptacles by navigating to and inspecting each one until…
alfworld-search-pattern-executor
Systematically searches a sequence of likely locations for a target object based on common sense. Use when you need to find a specific object and know which receptacles to check but not which one contains it. Takes a list of candidate receptacles, orchestrates navigation and inspection, and outputs when the target is…
ux-ui-analyze-single-page
Analyze exactly one captured UI page (from uxuimap screenshots + request JSON) and immediately write/update uxuimap/pages/{page}.md in neutral descriptive language. Use when asked to analyze screenshots, rewrite corresponding analysis immediately, or avoid memory/context saturation.