Humanizer

sponsored by cfo.ai

Humanizer makes AI-written text sound like a person wrote it, without changing what it says. It is built on Wikipedia's Signs of AI writing, the guide Wikipedia editors use to catch AI-generated text, and it works in Claude Code, Codex, and any other agent that supports skills.

Before:

I'm thrilled to announce that shared drafts are finally here! 🚀 For months, our own team was drowning in files named final_v7.docx — and we knew there had to be a better way. Now two people can edit the same doc at once, with every change appearing live for both of them. It's not just a feature; it's a whole new way to collaborate. Comments stay anchored to the exact sentence they reference, even as the text around them evolves. And the best part? It's available today on every plan, completely free. Let that sink in.

After:

Shared drafts are out today. For months our own team passed around files named final_v7.docx, and we got sick of it. Now two people can edit the same doc at once and see each other's changes as they type. Comments stay attached to the sentence they're about, even when the text around it changes. It's free on every plan.

In a blind test, judges preferred Humanizer's rewrite over the original AI text 16 times out of 16 (#229).

Humanizer edits for human readers. It does not try to get past AI detectors, and detectors still flag most of its output.

The five strongest tells

These are the most common signs of AI writing, and Humanizer rewrites any of them on sight:

1. Not X but Y: "It's not just a feature, it's a shift."
2. One-line closers: "Let that sink in."
3. Sayings that sound deep: "At its core, what really matters is..."
4. A staged run-up: "Here's the thing." "Honestly?"
5. Arguing with no one: "I'm not saying X, but..."

Humanizer checks for 26 patterns in all.

Installation

Once installed, run it with /humanizer.

Claude Code

/plugin marketplace add blader/humanizer
/plugin install humanizer@humanizer

The plugin needs Claude Code 2.1.142 or newer; on older versions, use npx skills add blader/humanizer --global --agent claude-code.

Codex

npx skills add blader/humanizer --global --agent codex

pi

pi install git:github.com/blader/humanizer

Add -l to install it only in the current project. pi update --extensions pulls new versions.

Claude.ai and Claude Desktop

Download this repository as a ZIP (Code → Download ZIP) and upload it as a skill in Settings.

Other agents

npx skills add blader/humanizer --global --agent '*'

This installs Humanizer for every agent the Skills CLI supports, including Gemini CLI, GitHub Copilot, and Windsurf. Leave off --global in any command above to install it only in the current project. For an agent the Skills CLI does not know, copy SKILL.md into its skill folder.

Usage

Call the skill directly:

/humanizer

[paste your text here]

Or ask in plain language:

Please humanize this text: [your text]

To rewrite a file, give Humanizer its path:

Humanize the prose in docs/launch-post.md

Humanizer reads the current file in full before editing, including files it wrote earlier in the session. Its summary states how many sections it reviewed and identifies any it could not cover.

Match your voice

If you want the rewrite to sound more like you, include a sample:

/humanizer

Here's a sample of my writing for voice matching:
[paste 2-3 paragraphs of your own writing]

Now humanize this text:
[paste AI text to humanize]

Humanizer follows the sample's rhythm, word choice, punctuation, and deliberate quirks, including dashes if you use them.

How it works

A language model writes whatever is most likely to come next, so by default it makes the choice that fits the widest range of readers and subjects. A person chooses for one reader and one subject. Every tell Humanizer looks for is a form of that default choice: a sentence that signals importance instead of adding a fact, rhythm or formatting applied by rule, an ordinary fact dressed as a pivotal one, text left over from the chat, or a reply that re-explains what the reader already knows.

"LLMs use statistical algorithms to guess what should come next. The result tends toward the most statistically likely result that applies to the widest variety of cases." Wikipedia, "Signs of AI writing"

Humanizer marks every tell it finds, strongest first. It drafts a rewrite and may merge, split, or reorder sentences and paragraphs, then checks the draft against the patterns and the original claims and writes the final version. Where the text is generic, it adds a specific detail it knows to be true, and it keeps every claim the original made.

When you paste text, Humanizer shows its work: the first rewrite, a short critique of anything that still sounds artificial, and the final version. Point it at a file and it changes only the prose, leaving code, data, frontmatter, and link targets alone. Personal writing keeps the writer's opinions and quirks. Technical and reference prose stays neutral and plain.

The 26 patterns

Humanizer numbers the patterns from strongest and most common to weakest. It edits any of the first five the first time it sees one, and acts on a pattern marked weak alone only when several tells share a passage, because a careful writer may use any one of them on purpose.

This is the beginning of the README. Read the rest at the original. Read the full README ↗