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 YPares/agent-skills --skill nix-profile-managergit clone --depth 1 https://github.com/YPares/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/ypares/agent-skills/nix-profile-manager)<a href="https://agentmods.dev/skills/ypares/agent-skills/nix-profile-manager"><img src="https://agentmods.dev/badge/skills/ypares/agent-skills/nix-profile-manager/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/ypares/agent-skills/nix-profile-manager"><img src="https://agentmods.dev/badge/skills/ypares/agent-skills/nix-profile-manager.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 | $0.00034 | $0.01230 |
| Opus 5 | $0.00017 | $0.00615 |
| Sonnet 5 | $0.00007 | $0.00246 |
| Haiku 4.5 | $0.00003 | $0.00123 |
Grade B, and why
nix-profile-manager scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 11d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
This skill enables agents to maintain a local Nix profile in a user-provided directory, allowing dynamic installation of tools without requiring system-wide package management or sudo access. How it starts
The opening of the file, as written. The whole thing — 149 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Nix Profile Manager for Agents
Overview
This skill enables agents to maintain a local Nix profile in a user-provided directory, allowing dynamic installation of tools without requiring system-wide package management or sudo access.
Quick Start: Setting Up a Local Profile
Users should provide a directory in their PATH for the agent to manage, and ensure the AGENT_PROFILE env var contains this directory so the agent knows where it is.
Then the agent just does:
nix profile add --profile "$AGENT_PROFILE" "nixpkgs#git"
The --profile flag tells Nix to store the profile metadata in that location.
The bin dir created by Nix in the profile must be in the PATH.
NOTE: on older Nix versions, the add sub-command was called install. Keep this in mind if you get errors saying that "add" does not exist.
Core Concepts
Profiles
A profile is a directory containing:
manifest.json- list of installed packages and their flake referencesbin,lib,share, etc. - folders with symlinks to binaries, libs, docs in the Nix store
When you run nix profile add, Nix updates the manifest and recreates symlinks.
Flakes
A flake is a standardized Nix package collection with:
- A
flake.nixfile defining inputs and outputs - Deterministic versioning via
flake.lock - Multiple output schemes (packages, overlays, modules, etc.)
Common flakes:
nixpkgs- Standard package library (the default registry), usually an alias forgithub:NixOS/nixpkgs/nixpkgs-unstable- Custom flakes from GitHub (e.g.,
github:user/repo)
Packages vs. Flakes
- Package: A single tool (e.g.,
git,python311) - Flake: A collection of packages, accessed as
<flake>#<package>
IMPORTANT: In some flakes (like nixpkgs) packages can be nested: <flake>#<scope>.<package>
Essential Commands
Search for Packages
# Search in nixpkgs flake:
nix search nixpkgs git
# Search in specific (fully qualified) flake
nix search "github:user/repo[/branch]" <package-name>
# Or get a more detailed JSON output
nix search nixpkgs python3 --json | jq '.[].pname'
What ships with it
4 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.
- 11d ago First seen · 149 lines · 34 tokens per session scan B d4a5f672d32e
nix-profile-manager is a skill published in the GitHub repository YPares/agent-skills (30 stars, last pushed yesterday), licensed MIT. It adds 34 tokens to every session and 1,230 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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riglet-creator
Creating effective riglets means writing knowledge (SKILL.md) that agents will rely on. This guide focuses on how to write high-quality documentation for riglets, organized efficiently.
nix-module-system
Practical knowledge about lib.evalModules that's hard to find in official docs.
code-search
Fast, efficient utilities for searching code and browsing file hierarchies.
Summarize document text and identify its main claims, evidence, and unanswered questions.
claude-md-improver
Audit and improve CLAUDE.md files in repositories. Use when user asks to check, audit, update, improve, or fix CLAUDE.md files. Scans for all CLAUDE.md files, evaluates quality against templates, outputs quality report, then makes targeted updates. Also use when the user mentions "CLAUDE.md maintenance" or "project…