Agent skill

Alloc Tracker

A skill your agent uses when you need to measure per-phase memory allocation statistics to investigate memory usage.

Apache-2.0Auto-check passedData & Analytics

Install Alloc Tracker

skills CLI

$ npx skills add coreos/chunkah --skill alloc-tracker -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install coreos/chunkah alloc-tracker --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/coreos/chunkah.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/alloc-tracker .claude/skills/alloc-tracker && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "alloc-tracker" agent skill from https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker into .claude/skills/alloc-tracker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "alloc-tracker", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add coreos/chunkah --skill alloc-tracker -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install coreos/chunkah alloc-tracker --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/coreos/chunkah.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/alloc-tracker .agents/skills/alloc-tracker && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "alloc-tracker" agent skill from https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker into .agents/skills/alloc-tracker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "alloc-tracker", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add coreos/chunkah --skill alloc-tracker -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install coreos/chunkah alloc-tracker --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/coreos/chunkah.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/alloc-tracker .cursor/skills/alloc-tracker && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "alloc-tracker" agent skill from https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker into .cursor/skills/alloc-tracker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "alloc-tracker", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/coreos/chunkah.git --path .agents/skills/alloc-tracker

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add coreos/chunkah --skill alloc-tracker -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install coreos/chunkah alloc-tracker --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/coreos/chunkah.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/alloc-tracker .gemini/skills/alloc-tracker && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "alloc-tracker" agent skill from https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker into .gemini/skills/alloc-tracker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "alloc-tracker", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install coreos/chunkah alloc-tracker

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add coreos/chunkah --skill alloc-tracker -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/coreos/chunkah.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/alloc-tracker .github/skills/alloc-tracker && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "alloc-tracker" agent skill from https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker into .github/skills/alloc-tracker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "alloc-tracker", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add coreos/chunkah --skill alloc-tracker -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install coreos/chunkah alloc-tracker --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/coreos/chunkah.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/alloc-tracker .opencode/skills/alloc-tracker && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "alloc-tracker" agent skill from https://github.com/coreos/chunkah/tree/main/.agents/skills/alloc-tracker into .opencode/skills/alloc-tracker/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "alloc-tracker", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: alloc-tracker
GitHub stars: 148
Token cost: ~526 tokens
SKILL.md length: 125 words
Files: 1
Skills in repo: 4
Repo updated: Oct 5, 2026
First seen: Oct 7, 2026
Licence: Apache-2.0

At a glance

A skill your agent uses when you need to measure per-phase memory allocation statistics to investigate memory usage.

Works in 5 steps: Add the dependency (feature-gated) → Register the global allocator → Instrument phases in cmd_build → …
You need to measure per-phase memory allocation statistics to investigate memory usage
SKILL.md covers 1. Add the dependency…, 2. Register the global allocator, 3. Instrument phases in… and 4. Build and run, plus 1 more section
Calls just

What it does

Alloc Tracker is an agent skill from coreos/chunkah. Use when you need to measure per-phase memory allocation statistics to investigate memory usage.

Its SKILL.md is about 530 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Data & Analytics, covering Statistics. The repository describes itself as: An OCI building tool for content-based layers. The licence is Apache-2.0.

When your agent uses it

You need to measure per-phase memory allocation statistics to investigate memory usage
Tasks that involve Statistics

Example prompts

“/alloc-tracker”

Workflow steps

5 steps, taken from the step headings in SKILL.md.

Add the dependency (feature-gated)
Register the global allocator
Instrument phases in cmd_build
Build and run
Clean up

What it can do on your machine

Read from SKILL.md and the folder at commit 780bcd2. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
- just
From the folder's file list and the shell code blocks in SKILL.md.
Network
Links to these hosts (documentation or services it may open):
- crates.io
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Alloc Tracker loads about 526 tokens when it runs. Until then it costs about 28 tokens; SKILL.md has 125 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~28
When it runs · the whole SKILL.md, loaded when a task matches: ~526

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from coreos/chunkah at commit 780bcd2, republished under its Apache-2.0 licence (© coreos). 125 words, ~526 tokens.

Download SKILL.mdSave it as .claude/skills/alloc-tracker/SKILL.md (or your agent's skills folder).

name: alloc-tracker
description: Use when you need to measure per-phase memory allocation statistics to investigate memory usage.

Memory Profiling with alloc_tracker

Use the alloc_tracker crate to measure per-phase allocation statistics. This is useful for identifying which phases of the pipeline allocate the most memory.

Note: the numbers are cumulative allocations (not peak live memory). Use /usr/bin/time -v to measure peak RSS, or just heaptrack for detailed heap profiling.

Note: print to stderr (eprint!), not stdout, since stdout carries the OCI archive.

1. Add the dependency (feature-gated)

In Cargo.toml:

toml

[features]
alloc_tracker = ["dep:alloc_tracker"]

[dependencies]
alloc_tracker = { version = "0.5", optional = true }

2. Register the global allocator

In src/main.rs (after imports):

rust

#[cfg(feature = "alloc_tracker")]
#[global_allocator]
static ALLOCATOR: alloc_tracker::Allocator<std::alloc::System> =
    alloc_tracker::Allocator::system();

3. Instrument phases in cmd_build

In src/cmd_build.rs, create a session and wrap phases in spans:

rust

#[cfg(feature = "alloc_tracker")]
let alloc_session = alloc_tracker::Session::new();

let files = {
    #[cfg(feature = "alloc_tracker")]
    let _span = alloc_session.operation("scan").measure_process();
    // ... scan code ...
};

// ... repeat for components, packing, oci_build ...

#[cfg(feature = "alloc_tracker")]
eprint!("{}", alloc_session.to_report());

4. Build and run

bash

just buildimg --no-chunk --features alloc_tracker
just split $IMG

This prints a table like:

text

| Operation  | Mean bytes | Mean count |
|------------|------------|------------|
| components |  252055871 |    1049679 |
| oci_build  |   29006550 |    1106100 |
| packing    |    9073500 |       3033 |
| scan       |   99375505 |     607710 |

5. Clean up

Remove the alloc_tracker dependency, feature, global allocator, and instrumentation spans before committing. These are for local investigation only.

Files

Just SKILL.md in .agents/skills/alloc-tracker of coreos/chunkah.

Open the folder on GitHubat commit 780bcd2

Compare with similar skills

Alloc Tracker next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Alloc Tracker compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Alloc Tracker this skillcoreos/chunkah	148	—	~526	Automated safety check: Pass	Apache-2.0	2 days ago
Sandbox Benchvercel/next.js	143k	—	~4.1k	Automated safety check: Pass	MIT	today
Statistical Analysisspacering-net/codeg	3.8k	4 repos	~5k	Automated safety check: Pass	MIT	today
StatsmodelszLanqing/codex-claude-academic-skills	4.6k	16 repos	~4.9k	Automated safety check: Pass	BSD-3-Clause	4 mo ago
Statistical Powerspacering-net/codeg	3.8k	2 repos	~3.6k	Automated safety check: Notes	MIT	today
AI Daily DigestvigorX777/ai-daily-digest	1.6k	—	~1.3k	Automated safety check: Pass	None	7 mo ago

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Questions about Alloc Tracker

What does Alloc Tracker do?

A skill your agent uses when you need to measure per-phase memory allocation statistics to investigate memory usage. Alloc Tracker is an agent skill from coreos/chunkah. Use when you need to measure per-phase memory allocation statistics to investigate memory usage.

When should I use Alloc Tracker?

Alloc Tracker fits situations like: you need to measure per-phase memory allocation statistics to investigate memory usage; tasks that involve Statistics.

How do I install Alloc Tracker in Claude Code?

Run `npx skills add coreos/chunkah --skill alloc-tracker -a claude-code`. Or copy the skill folder (.agents/skills/alloc-tracker in coreos/chunkah) into .claude/skills/alloc-tracker in your project. Claude Code loads it when a task matches its description.

How do I install Alloc Tracker in Codex?

Run `npx skills add coreos/chunkah --skill alloc-tracker -a codex`. Or copy the skill folder (.agents/skills/alloc-tracker in coreos/chunkah) into .agents/skills/alloc-tracker in your project. Codex loads it when a task matches its description.

Can I use Alloc Tracker in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add coreos/chunkah --skill alloc-tracker -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/alloc-tracker, .gemini/skills/alloc-tracker, .github/skills/alloc-tracker and .opencode/skills/alloc-tracker in your project.

What does Alloc Tracker need to run?

Going by SKILL.md and its folder, Alloc Tracker needs the command-line tools its instructions call (just).

Does Alloc Tracker access the network?

SKILL.md names 1 domain. As links in the text: crates.io. This is read from the text; nothing was executed.

Is Alloc Tracker safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Alloc Tracker use?

Alloc Tracker is published under the Apache-2.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Alloc Tracker use?

About 526 tokens (SKILL.md is roughly 2.1k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Alloc Tracker?

Skills that share tags, products or a category with Alloc Tracker: Sandbox Bench (vercel/next.js, 143k stars), Statistical Analysis (spacering-net/codeg, 3.8k stars), Statsmodels (zLanqing/codex-claude-academic-skills, 4.6k stars) and Statistical Power (spacering-net/codeg, 3.8k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Alloc Tracker?

coreos (a GitHub organization) maintains it in coreos/chunkah, which has 148 GitHub stars. The repository holds 4 skills in this directory. The repository was last updated on October 5, 2026.

Source: coreos/chunkah on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Alloc Tracker

Install Alloc Tracker

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Memory Profiling with alloc_tracker

1. Add the dependency (feature-gated)

2. Register the global allocator

3. Instrument phases in cmd_build

4. Build and run

5. Clean up

Files

Compare with similar skills

Similar skills

Sandbox Bench

Statistical Analysis

Statsmodels

Statistical Power

AI Daily Digest

Agent Session Monitor

More from coreos/chunkah

Polish Notes

Extract Oci Archive

Benchmark Packing

Questions about Alloc Tracker

Install Alloc Tracker

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Memory Profiling with alloc_tracker

1. Add the dependency (feature-gated)

2. Register the global allocator

3. Instrument phases in cmd_build

4. Build and run

5. Clean up

Files

Compare with similar skills

Similar skills

More from coreos/chunkah

Related

Questions about Alloc Tracker