Field notes. John Arndt, Soxoa. Published .
Most people asking AI to write in their voice hand it three recent posts. The model copies the short paragraphs, repeats a favorite phrase and turns every subject into the same performance.
The missing piece is context. An email asking for a refund, a comment on a colleague's post and a business article serve different jobs. A useful voice guide explains those differences so the next draft can make the right choice.
We have already done the underlying work. A voice study completed in August 2026 used cleaned, attributed writing, observed public posts, explicit preferences and a narrowly supported meeting register. It produced a detailed private guide and a separate shareable prompt. The reusable method is the skill here. The person's private correspondence stays private.
Start by deciding what counts as evidence
Before analyzing sentence length, identify who wrote each sample and what happened to it. A person-authored message, a published article with an editor, an approved AI-assisted draft and a template are different sources.
All can help. They answer different questions. A published article can establish approved professional positioning. It cannot establish that every sentence reflects unassisted writing. A stated preference can guide future work even when older messages do something else.
The skill keeps a source ledger with date, channel, audience, authorship status and permission to quote. It removes forwarded messages, quoted replies, signatures and automatic notices. It also deduplicates repeated material. Otherwise, somebody else's wording or one frequently forwarded email can become a supposedly defining habit.
This is where the work becomes useful. The guide can explain why it recommends a choice and how much evidence supports it.
Build a few usable registers
Imagine a consultant supplies operational emails, public articles and internal chat. This is an illustrative example. The emails may consistently lead with the requested action. The articles may explain a mechanism before offering a recommendation. Internal chat may omit context because both people already know the project.
Combining those patterns into one average voice would produce awkward articles and overexplained chat messages.
A better guide creates separate register cards. Each card explains how to open, how much detail the situation needs, how to express uncertainty and where to stop. Shared preferences can sit above the cards. The writer's current instructions take priority over imitation.
Examples help when they show a decision. They should be newly written and labeled as illustrative. Private messages do not need to become public training material just because they informed a private analysis.
Give the next draft a small instruction set
The finished package should contain a core description, a few relevant register cards and a portable prompt. It should also say where the evidence is thin.
A transcript can support observations about attributed language. It cannot, by itself, establish someone's accent, pitch or physical delivery. A handful of social posts cannot establish how that person handles a serious customer dispute. Missing evidence belongs in the guide.
The new Claude skill draft, build-voice-guide, packages these decisions into a repeatable workflow. It needs authorized writing samples and the intended channels. It produces a guide, a shareable drafting prompt and a coverage summary. The historical method has been used; this newly packaged Claude version still needs a trial in Claude.
Try this request:
“Use build-voice-guide on these authorized samples. Build separate cards for operational email and long-form articles. Distinguish authored, edited and synthetic material. Keep all private excerpts out of the shareable prompt.”
Then test the guide on two real tasks and ask the person which choices feel right. Repeated corrections are useful evidence. A model announcing that it has captured your voice is considerably less useful.
Start with one channel where you have enough material and a real draft to improve. That gives the guide a job and gives you a way to judge it.
Get the skill
build-voice-guide is part of the free Soxoa Ops plugin for Claude. In Claude Code, add the marketplace with /plugin marketplace add johnarndt/soxoa-claude-plugins, then run /plugin install soxoa-ops@soxoa-plugins. You can read the skill on GitHub before installing it, or copy its folder into ~/.claude/skills/.