Project Sizing Guide

Q: What is a Claude Code skill and how does the Project Sizing Guide skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Project Sizing Guide is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the General category. Learn more at https://claudskills.com/learn/what-is-skill-md/.

Category: General · Sub-category: general-misc · Last updated: 2026-06-06

Software project effort estimation assistant. Outputs three-point estimates (optimistic/most-likely/pessimistic values with confidence intervals), T-shirt sizes, or Function Point Analysis (FPA) counts. Triggered when users ask 'how long will this feature take,' need to assess project workload, perform PERT estimation, T-shirt sizing, FPA, sprint planning, or quote-based effort breakdowns.

Security AStatic scan found no risk patternsHow grading works ›

From the source SKILL.md

Helps teams produce scientifically grounded effort estimates for software projects, based on three major methodologies: Three-Point Estimation (PERT), T-shirt Sizing, and Function Point Analysis (FPA). Outputs optimistic, most-likely, and pessimistic values along with risk intervals.

What this skill does

Project Sizing Guide is a community-contributed Claude Code skill in the general-misc sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/project-sizing-guide/ and loads when your prompt matches the skill's trigger.

Who uses this skill

The Project Sizing Guide Claude Code skill is built for Claude Code users and developers across all disciplines looking for general-purpose AI assistance. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 196,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/project-sizing-guide
curl -L https://claudskills.com/skills/project-sizing-guide/SKILL.md \
  -o ~/.claude/skills/project-sizing-guide/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/project-sizing-guide/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/project-sizing-guide/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\project-sizing-guide\SKILL.md on Windows. See the full install guide for step-by-step instructions.

📱 Install from your phone or desktop Telegram

Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

Frequently asked questions

How do I install the Project Sizing Guide Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/project-sizing-guide/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.

What does the Project Sizing Guide skill do?

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

When should I use the Project Sizing Guide skill?

Use Project Sizing Guide when your Claude Code task falls under the General category — specifically in the general misc area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use Project Sizing Guide" or describe the task and let Claude pick). Browse related skills at /category/general/.

What is a Claude Code skill and how does the Project Sizing Guide skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Project Sizing Guide is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the General category. Learn more at /learn/what-is-a-claude-skill/.

Attribution & license

Source: https://github.com/zebbern/claude-code-guide/blob/HEAD/skills/project-sizing-guide/SKILL.md
License: MIT
Author: zebbern

Cite this skill

If you reference this skill in a blog post, paper, or documentation, you can cite it as:

APA

zebbern. (2026). Project Sizing Guide [Claude Code skill]. ClaudSkills. https://claudskills.com/skills/project-sizing-guide/

BibTeX

@misc{project-sizing-guide-2026,
  author    = {zebbern},
  title     = {Project Sizing Guide [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/project-sizing-guide/}
}

Embed this skill

Promote, attribute, or link this skill from your own README, blog post, or documentation. All three snippets are free to use — no sign-up, no API key. More distribution surfaces →

Badge

[![ClaudSkills](https://claudskills.com/badge/project-sizing-guide.svg)](https://claudskills.com/skills/project-sizing-guide/?utm_source=badge&utm_medium=readme&utm_campaign=skill_badge)

Security scan

Grade A · scanned 2026-09-28 — free static scan against the OWASP Agentic Skills Top 10.

No risk patterns were found in any of the ten OWASP-aligned categories. How grading works ›

✓ Prompt injection
✓ Data exfiltration
✓ Supply chain
✓ Reverse shell
✓ Credentials
✓ Execution
✓ Filesystem
✓ Persistence
✓ Obfuscation
✓ Network

Show this grade on your repo (click to copy):

[![Security: A](https://img.shields.io/badge/Security-A-2e7d32)](https://claudskills.com/skills/project-sizing-guide/#security)

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Part of ClaudSkills — the open registry for Claude Skills & Claude Code Skills. · What's New · Install guide · About · llms.txt

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