Docs & Writing vs Testing · both proven

changelog-generator vs differential-review

Both skills were run through Claude twice: once on a fixed brief without the skill, once with it. The briefs differ because each is written for the job the skill claims to do, so compare each skill against its own baseline, then decide which difference matters for your work. They are in different categories, so this is a choice of job, not a head-to-head on the same job.

changelog-generator

Automatically creates user-facing changelogs from git commits by analyzing commit history, categorizing changes, and transforming technical commits into clear, customer-friendly release notes. Turns hours of manual changelog writing into minutes of automated generation.

Category: Docs & Writing
Source: ComposioHQ/awesome-claude-skills
License: Not stated
Proof model: claude-opus-5-5
Brief: “Turn these git commits into a user-facing changelog page for version 2.4.0 of Ledgerly, a small-business invoicing app, as a single HTML page. Commits: 'feat: recurring invoices with weekly, monthly and custom schedules'; 'feat: export invoices to CSV from the list view'; 'fix: PDF totals rounded incorrectly for invoices with more than 50 line items'; 'fix: late-fee reminder emails sent twice when a client had two contacts'; 'chore: bump node to 22'; 'refactor: move tax calculation into shared module'; 'feat: Stripe payouts show in the dashboard with a status badge'; 'fix: dark mode contrast on the settings page'; 'docs: update API examples for the invoices endpoint'.”
Skill commit: be2a406

Without the skillWith changelog-generator

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Without, runWith changelog-generator, run3 independent runs per side, none selected by hand.

Download the with-skill page

differential-review

Performs security-focused differential review of code changes. Adapts analysis depth to codebase size, uses git blame for context, calculates blast radius by counting callers, checks test coverage of modified code, and generates a markdown report. Use when reviewing a PR, commit, or diff for security vulnerabilities, checking whether a change re-introduces a previously fixed bug, asking what else…

Category: Testing
Source: trailofbits/skills
License: Other
Proof model: claude-opus-5-5
Brief: “Do a security-focused review of this change and present it as a single HTML page. Commit: "Allow admins to impersonate users for support" +app.get('/admin/impersonate/:id', async (req, res) => { + if (req.cookies.role !== 'admin') return res.sendStatus(403); + const user = await User.findById(req.params.id); + req.session.userId = user.id; + res.redirect(req.query.next || '/'); +});”
Skill commit: 2be6433

Without the skillWith differential-review

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Without, runWith differential-review, run3 independent runs per side, none selected by hand.

Download the with-skill page

We don’t pick a winner for you: the pages are the evidence. Both proofs can be repeated with the brief, model and commit shown above. See alternatives to changelog-generator or alternatives to differential-review.