Second Brain Backfill logo

Second Brain Backfill

CommunityPopular
undefined-ui
second-brain-backfill

Import a large archive into the vault in controlled batches: triage what is worth ingesting, process oldest first, checkpoint after every batch, and keep cost visible. Use this skill whenever the user wants to import years of bookmarks, an export from another notes app, a downloads folder, a chat history dump, or says "backfill", "bulk import", "process my archive". Do NOT use for ingesting one or a few new sources, which is second-brain-ingest.

Overview

Publisherundefined-ui
Repositorysecond-brain-os
Skill namesecond-brain-backfill
Stars
1K
Forks
166
Bundled files
Instructions only
LicenseMIT
Links
  • Markdown instructions

    A SKILL.md file the model loads on demand, so it only costs tokens when a request actually matches.

  • Works with any LLM

    AI skills are plain Markdown, not provider-specific code, so this works with GPT, Claude, Gemini, Grok, or a local model.

  • Self-contained

    Everything the model needs lives in the instructions — no extra files to sync.

  • Open source

    Published by undefined-ui on GitHub. Read the source before you install it.

Installation

Install the Second Brain Backfill AI skill in TypingMind to use it with any LLM, or drop it into another agent that reads SKILL.md.

1

Install in TypingMind

TypingMind installs a skill straight from its GitHub folder — it reads SKILL.md, bundles the resource files, and stores the result locally.

  1. Open the app and go to Plugins → Skills.
  2. Choose "Install from GitHub".
  3. Paste the skill folder URL below and confirm.
    https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-backfill
  4. Enable the skill in any chat where you want it available.
Plugins → Skills → Add skill → From GitHub URL, then paste the folder URL and press Continue.
2

Install in another agent

Any agent that reads the Agent Skills format can use this skill — copy the folder into that agent's skills directory.

Claude Code — .claude/skills
git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git /tmp/second-brain-os
mkdir -p .claude/skills
cp -r /tmp/second-brain-os/skills/second-brain-backfill .claude/skills/second-brain-backfill
Restart Claude Code after copying so it picks up the new skill.

Use it in TypingMind

Enable Second Brain Backfill in any TypingMind chat and the model takes it from there. Its name and description sit in the system prompt, and the moment a request matches, the model loads the full instructions itself — you never invoke it by hand, and it costs no tokens until it is actually used.

The model loads Second Brain Backfill on its own as soon as a request matches it.

Works with any AI model

AI skills are plain Markdown instructions rather than provider-specific code, so Second Brain Backfill is not tied to the model it was written for. Install it once in TypingMind and use it with GPT-5, Claude, Gemini, Grok, DeepSeek, Mistral, Llama, or a local model you run yourself — all on your own API keys.

  • Loaded only when it is needed

    The system prompt carries just the name and description. The instructions are fetched on the first matching request, so an idle skill costs nothing.

  • Switch models mid-chat

    Because the skill is instructions rather than code, changing model does not break it — the next model reads the same SKILL.md.

Skill instructions

This is the SKILL.md content the model loads. Read it before installing — a skill is instructions your model will follow.

Backfill an archive

A backfill is where cost and quality both go wrong quietly. Done in the wrong order it also inverts the vault's history, because later sources should update pages that earlier ones created.

Core rule

Oldest first, ten sources per batch, stop for a go-ahead between batches.

Workflow

  1. Triage before ingesting. Read titles and first paragraphs. Sort into worth-ingesting, keep-in-raw, and delete. Most archives are half dead links and things saved but never opened.
  2. Order by date, oldest first. Run it the other way and every old source arrives as a contradiction against a page that already has the final answer.
  3. Batch of ten. Ingest following second-brain-ingest.
  4. Checkpoint: update index.md, append to log.md, commit with the batch range in the message, report counts.
  5. Stop and wait before the next batch.
  6. Full lint at the end. Large imports always leave orphans and duplicates.

Output format

Batch <n>/<total>: <range>
Ingested: <n> sources -> <n> new pages, <n> updated, <n> links
Skipped: <n> (reason)
Running total: <n> of <n>
Next batch: <what it contains>

Calibration

Read every page the first batch produced, all of them. A flaw you let through in batch one is a flaw in four hundred pages by the end, and fixing it afterwards costs more than the original run.

If the archive is over about two hundred sources, propose a filter before starting rather than quoting the full cost.

Frequently asked questions

What does the Second Brain Backfill AI skill do?

Import a large archive into the vault in controlled batches: triage what is worth ingesting, process oldest first, checkpoint after every batch, and keep cost visible. Use this skill whenever the user wants to import years of bookmarks, an export from another notes app, a downloads folder, a chat history dump, or says "backfill", "bulk import", "process my archive". Do NOT use for ingesting one or a few new sources, which is second-brain-ingest.

Why use Second Brain Backfill on TypingMind?

Because you install it once and use it with any model. Second Brain Backfill is plain Markdown rather than provider-specific code, so the same skill runs on GPT-5, Claude, Gemini, Grok, or a local model — and you can switch model mid-chat without it breaking. TypingMind runs on your own API keys, so you pay providers directly instead of a per-seat subscription, and your skills and chats stay in your own storage.

How do I install Second Brain Backfill in TypingMind?

Open Plugins → Skills → Install from GitHub in TypingMind and paste https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-backfill. TypingMind reads its SKILL.md and installs it as a skill you can enable per chat.

Which AI models can use Second Brain Backfill?

Any model you connect in TypingMind. AI skills are plain Markdown instructions rather than provider-specific code, so GPT, Claude, Gemini, Grok, and local models can all load this skill when a request matches it.

How many AI models can I use with Second Brain Backfill?

As many as you like. As long as a model supports skills, you can use Second Brain Backfill with it — GPT, Claude, Gemini, Grok, DeepSeek, Mistral, Llama and more — all on TypingMind with your own API keys.

Is the Second Brain Backfill AI skill free?

Yes. It is published on GitHub by undefined-ui under the MIT license. You only pay your own AI provider for the tokens you use.

What are AI skills?

An AI skill is a reusable instruction bundle that teaches an AI model how to do one specific task. It follows the open Agent Skills format: a SKILL.md file with a name and description, plus any scripts, templates or reference files the model may need. The model reads the instructions only when your request matches the skill, so an installed skill costs nothing until it is used.

How are AI skills different from plugins or MCP servers?

A plugin or MCP server gives a model new tools to call — code that runs somewhere and returns a result. An AI skill gives the model knowledge and process instead: how to approach a task, which steps to follow, what good output looks like. Skills are plain Markdown, so they need no server, no API key and no runtime, and they work with any model.

View all

Set up your own AI workspace now

Get notified about new features and future giveaways by subscribing to our newsletter 👇