Other vs Testing · both proven

internal-comms vs writing-guidelines

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.

internal-comms

A set of resources to help me write all kinds of internal communications, using the formats that my company likes to use. Claude should use this skill whenever asked to write some sort of internal communications (status reports, leadership updates, 3P updates, company newsletters, FAQs, incident reports, project updates, etc.).

Category: Other
Source: anthropics/skills
License: Not stated
Proof model: claude-opus-5-5
Brief: “Write this week's status update for the Checkout Redesign project as a single HTML page for the leadership channel. Facts to use: the new cart page shipped to 10% of traffic on Tuesday; conversion in the test group is up 2.1% so far; the payments team is two days late on the saved-cards work; a legal review of the new terms copy is still open; launch to 100% is planned for the 30th if the saved-cards work lands by Friday. Keep it short enough to read in a minute.”
Skill commit: dbd4588

Without the skillWith internal-comms

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Without, runWith internal-comms, run3 independent runs per side, none selected by hand.

Download the with-skill page

writing-guidelines

Review docs/prose for Writing Guidelines compliance. Use when asked to "review my docs", "check writing style", "audit prose", "review docs voice and tone", or "check this page against the writing handbook".

Category: Testing
Source: vercel-labs/agent-skills
License: Not stated
Proof model: claude-opus-5-5
Brief: “Review and rewrite this getting-started page for Pipewell, a data pipeline CLI. The draft opens with two paragraphs of company history, mixes 'you' and 'the user', buries the install command in the fourth paragraph, uses passive voice throughout, and ends without a next step. Write the improved page as a single HTML document, followed by a short list of what you changed and why.”
Skill commit: 063bee9

Without the skillWith writing-guidelines

⇆

Without, runWith writing-guidelines, 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 internal-comms or alternatives to writing-guidelines.