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Applied AI

The AI wiki: stop re-reading, start compounding

MRMatthew RogersFounder & CEO, Preux10 June 2026 · 8 min read

Watch an assistant answer a question about your business and you will see something wasteful: it reads the same scattered documents it read yesterday, reconstructs the same understanding, answers, and then forgets all of it when the session ends. The reading was rework. The synthesis evaporated. An AI wiki fixes this with an old idea and a new librarian: write the understanding down once, keep it linked and current, and make everything, human or machine, read the summary before the source.

The shape of the idea has been circling for a while; Andrej Karpathy has sketched it as the wiki whose maintainer is a language model. The team writes and works as normal. The model does the librarianship: ingesting new material, updating the summary pages, linking concepts to each other, and flagging contradictions for a human to settle. Synthesis happens once, on ingestion, instead of on every single question.

SourcesDOCS · THREADS · DECISIONSLibrarianAGENT · DAILYSUMMARISE · CROSS-LINK · FLAGWikiSUMMARIES · CROSS-LINKEDSearchPEOPLE + AGENTSNEW LEARNINGS FLOW BACK AS SOURCES
The cycle: raw sources flow through a librarian agent into cross-linked summary pages, a search index serves people and agents, and what they learn flows back in as new sources.

01

Why summaries beat sources

Context windows are large now, but attention is not. Stuff a model's context with two hundred thousand tokens of raw documents and the answer quality degrades; the signal drowns in its own supporting material. A curated page that already contains the synthesis costs a fraction of the tokens and answers more accurately, because a human-reviewed distillation is denser in truth than any pile of originals.

Whole repo pasted into context≈ 200k tokens

noise wins, recall degrades

Curated wiki page≈ 6k tokens

synthesis done once, in advance

Search-retrieved snippet≈ 800 tokens

just-in-time, exactly on point

The same question, three ways. The economics of curation: a maintained summary is both cheaper and more accurate than re-reading sources, and a search hit on that summary is cheaper still.

Synthesis happens once, on ingestion, instead of on every single question.

In plain terms

A ship could make every sailor re-derive the route from raw star sightings each morning. Instead it keeps charts and a log: someone did the working once, wrote it down, and now everyone navigates from the summary. The AI wiki is charts and a log for your business, with the model as the navigator who keeps them current.

A hand-drawn world map in muted colours
Charts and a log: the working was done once, written down, and now every navigator starts from the summary.

02

The pattern, concretely

  • A sources folder. Anything new lands here: meeting notes, decisions, vendor docs, postmortems. Nobody formats anything.
  • A librarian pass, on a schedule. An agent reads what is new, updates the relevant summary pages, adds cross-links, and opens a change for review rather than editing silently.
  • Summary pages, one per concept. Short, current, dated, and linked to related pages, so a single retrieval brings connected understanding with it.
  • Contradiction flags. When a new source disagrees with an existing page, the librarian does not pick a winner. It flags the conflict for a human, because deciding truth is governance, not formatting.
  • A search index over the wiki, keyword and semantic together, so the answer to most questions is one small, current page instead of an archaeology dig.

The librarian is a scheduled job, not a product

# 07:10 every morning: ingest new sources, update pages, open a PR
10 7 * * * cd ~/team-wiki && ./librarian ingest sources/ --open-pr

Ours runs as a launchd job on a Mac and an Action in CI; cron shown for portability. The agent inside is a single well-prompted model call with file access. The pattern matters more than the runner.

03

Hygiene that keeps it trustworthy

A wiki rots the moment its readers stop trusting it, and trust dies through small things. Date-stamp claims, so stale advice looks stale. Keep pages short enough that updating one is a five-minute act, not a project. Let the librarian propose and humans approve, the same reads-free, writes-governed rule that protects any shared brain. And measure it honestly: when someone asks a question the wiki cannot answer, that is a missing page, and the librarian should draft it the same day.

A curved gallery of bookshelves in a library
A wiki earns trust the way a good library does: short shelves, current editions, and a catalogue that takes you straight to the page.

The habit that makes it stick

# Agents and people both: search the wiki before the sources
wikigrep "payment retry policy"   # keyword, instant
wikiask  "why did we drop provider X?"   # semantic, when you can't name it

Two search modes, one discipline: the wiki is the front door to institutional knowledge. We alias these to one keystroke each, because friction here decides whether the system lives.

Real pieces to build it from

ObsidianLocal-first markdownLinked markdown pages with backlinks and graph view. A wiki that both humans and models read natively.GitHub ActionsScheduled CIRun the librarian on a schedule with the wiki in a repository, so every change is a reviewable pull request.Claude CodeAnthropicHeadless mode makes a capable librarian: read sources, edit pages, open the PR, all from one scheduled command.RIripgrepOpen sourceThe keyword half of retrieval. Over a folder of short markdown pages, it is effectively instant.CHChromaOpen sourceLocal embeddings for the semantic half, so questions find pages even when the words do not match.NotionHosted alternativeIf the team already lives here, the same pattern works through its API; the librarian writes pages instead of files.
OnceHow many times any document should need to be deeply read. After that, its meaning lives in the wiki, linked and findable, and every future question starts from the summary.

04

Where this leads

Teams that run this for a few months describe the same shift: the wiki stops being documentation and becomes the organisation's working memory. New joiners read it and are dangerous in a week. Agents read it and stop hallucinating your own business back at you. And because the librarian never gets bored, the corner pages that no human would ever maintain stay current too. It is the least glamorous system we build for clients, and very possibly the highest-return one.

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