Promptlight logo
Menu
Back to Prompts

Prompt template

D-Mail - Send Messages to the Past

Workflow prompt for checkpoint-based context rewinds, letting an assistant send a compact message back to an earlier state with only the useful learnings.

productivity
time-travel
workflow
agent
context-management
system-prompt
Send a message to the past, just like sending a D-Mail in Steins;Gate.

You can see some user messages with CHECKPOINT {checkpoint_id} wrapped in `<system>` tags in the context. When you need to send a D-Mail, select one of the checkpoint IDs in these messages as the destination checkpoint ID.

When a D-Mail is sent, the system will revert the current context to the specified checkpoint. After reverting, you will no longer see any messages which you can currently see after that checkpoint. The message in the D-Mail will be appended to the end of the context. So, next time you will see all the messages before the checkpoint, plus the message in the D-Mail. You must make it very clear in the D-Mail message, tell your past self what you have done or changed, what you have learned and any other information that may be useful.

When sending a D-Mail, DO NOT do much explanation to the user. The user does not care about this. Just explain to your past self.

Usage notes

Context, setup, and extra guidance for this prompt.

Customization tips

Turn this into a reusable workflow, not a one-off prompt

  • Replace the generic context with your stack, domain, or customer segment before you run it.
  • Add constraints for tone, output format, and level of detail so the model matches your workflow.
  • Paste a real example input or diff to get results that are grounded instead of generic.
Published October 30, 2025
Source:Darren Angle on X

Related prompts

Keep exploring adjacent prompt templates for the same workflow or team use case.

workflowproductivity

Meeting Notes To Actions

Operations prompt for turning messy meeting notes into decisions, action items, owners, deadlines, and unresolved questions without losing important nuance.

productivityworkflow

Founder Weekly Review

Planning prompt for running a weekly founder review across wins, bottlenecks, open loops, priorities, and decisions that need real attention next week.

workflowproductivity

Onboarding Docs Builder

Documentation prompt for turning tribal knowledge, setup steps, and scattered links into a clearer onboarding guide for new teammates or contractors.

Want to save this prompt for later?

Get Promptlight to instantly access all your saved prompts with a keyboard shortcut.

Download for macOS

Try Promptlight UI live

Type, search, and enhance right here. It’s interactive.

Search mode

Find the right prompt in milliseconds.

Switch via Promptlight icon or ⇧ + Tab

  • Fuzzy search across titles and body text.
  • Favorites and file paths at a glance.
  • Keyboard-first: ↑↓ to navigate, ⏎ to copy.

A prompt library that fits how you already work

Promptlight combines fast local search, portable Markdown storage, and one-click enhancement so your best prompts stay useful instead of getting lost in chats.

Lightning-Fast Search

Fuzzy search through your prompts instantly. Find what you need in milliseconds with intelligent matching.

Enhancer Mode

Turn rough prompts into clear, detailed, or creative versions with one click.

Keyboard-First Workflow

Every action in Promptlight is keyboard-first. Launch with a shortcut, browse with a shortcut, copy with a shortcut.

Private & Secure Data

Your prompts are stored locally on your machine. No need to worry about your data being stored online. Your data is always private and secure.

Edit with Any App

Your prompts are plain markdown files. Edit them in VS Code, Obsidian, or any editor—changes sync instantly both ways.

Favorite Prompts

Mark your favorite prompts to pin them for quick access. No need to search for them every time.

Get Started Today

Download Promptlight for free, or send yourself the link if you're browsing on mobile and want to install it later on your Mac.

Download for macOS

Version 1.2.1 • 17.8 MB • macOS 10.13 (High Sierra) or later