Practical overview
When it fits
Use Sepia when working inside a compatible AI agent and the task calls for a defined writing operation, fiction revision beyond word choice, or professional prose guidance matched to the document’s venue.
Who it is for
- Writers revising fiction with a compatible AI agent.
- Developers and teams drafting or editing release notes, pull-request replies, postmortems, tickets or technical articles.
- Users of Claude Code, Codex, Grok Build, Antigravity, QwenPaw or another agent that supports the Agent Skills standard.
Documented uses
- Draft prose with the write operation.
- Diagnose writing without changing it using review.
- Make minimal edits with refactor.
- Rewrite from source facts and intent with recreate.
- Apply fiction-oriented structural revision or rules matched to a professional document type.
Requirements & limits
The project is published under the MIT license. The README identifies the Skills CLI as an installation route and describes native plugin packaging for several named agent environments.
- Sepia is an agent skill, not a standalone editing application; use it through a compatible agent environment.
- Its fiction workflow spans narrative architecture, discourse flow and surface style, while professional prose uses document-specific rules.
- Review diagnoses without editing; refactor makes minimal edits; recreate rewrites from source facts and intent.
- The README cautions against applying every fiction guideline, recommending a limited selection of changes.
- Repository materials describe the design rationale and workflows but do not establish detection outcomes for edited text.
Check current requirements in the official documentation. Source-based guidance does not mean OpenViST has run or independently tested this project.
Review prose with Sepia’s diagnostic operation
Use Sepia’s review operation to diagnose prose without editing it.
Before you start
- Sepia installed in an Agent Skills-compatible agent.
- A host with the Sepia review entry; its documented invocation varies by host.
Steps
Provide the prose to the compatible agent.
Invoke Sepia’s review operation using the host’s documented entry:
/sepia-reviewin Claude Code, Grok Build, or Antigravity, or$sepia-reviewin Codex.Read the diagnosis; the review operation is described as diagnose-only.
Expected outcome
The agent diagnoses the prose without making edits.
Guide limitations
- The source does not provide detailed invocation instructions for supplying prose to each host.
- Review diagnoses only; use another operation for edits.
- Compatibility is described by the project, not independently tested here.
Refactor prose with minimal edits
Use Sepia’s refactor operation to make minimal in-place edits to prose.
Before you start
- Sepia installed in an Agent Skills-compatible agent.
- A host with the Sepia refactor entry; its documented invocation varies by host.
- Source prose to edit.
Steps
Provide the source prose to the compatible agent.
Invoke Sepia’s refactor operation using the host’s documented entry:
/sepia-refactorin Claude Code, Grok Build, or Antigravity, or$sepia-refactorin Codex.Review the resulting minimal in-place edits.
Expected outcome
The agent makes minimal in-place edits to the provided prose.
Guide limitations
- The source does not provide detailed invocation instructions for supplying prose to each host.
- The refactor operation is described as minimal editing, not a full rewrite.
- Compatibility is described by the project, not independently tested here.
Sources & review
Source record details
- Source availability
- Active
- Sources checked
- 10 October 2026
- Original website title
- Nanako0129/sepia · Official homepage title · retained in its source language