diff --git a/quest/README.md b/quest/README.md
index 7f14fb0..fd65cb8 100644
--- a/quest/README.md
+++ b/quest/README.md
@@ -15,5 +15,5 @@ its scope, until it is scheduled.
 
 ## Required
 
-- [m0: immediate priorities](/quest/m0/README.md) - hosted worklets once a release ships assets()
+- [m0: immediate priorities](/quest/m0/README.md) - hosted worklets once a release ships assets(), lean agent context, and checks that pass locally
 - [m1: next](/quest/m1/README.md) - the Voice AI demo page and its live buffer view
diff --git a/quest/m0/README.md b/quest/m0/README.md
index 1363e4c..41ae743 100644
--- a/quest/m0/README.md
+++ b/quest/m0/README.md
@@ -5,7 +5,13 @@
 The sites host the `@moq` player worklets and workers themselves once a
 release ships `assets()`, so the hosted path gets real traffic.
 
+The agent context is lean and the checks cover what they claim, passing on a
+developer's machine.
+
 ## Required
 
+- [Lean AGENTS.md](/quest/m0/lean-agents-md.md) - agent context keeps only rules and conventions, no repo description
+- [Biome passes locally](/quest/m0/biome-local.md) - `just check` passes with Claude Code's local files present
+- [Type-check .astro files](/quest/m0/astro-typecheck.md) - `just check` covers `.astro` via the TypeScript 7.1 content mapper
 - [A release ships assets()](/quest/m0/assets-release.md) - the hosted worklet files exist on npm to copy
 - [Dogfood hosted worklets](/quest/m0/dogfood-assets.md) - the sites serve the @moq worklets and workers themselves
diff --git a/quest/m0/astro-typecheck.md b/quest/m0/astro-typecheck.md
new file mode 100644
index 0000000..c8b9afc
--- /dev/null
+++ b/quest/m0/astro-typecheck.md
@@ -0,0 +1,21 @@
+# [S] Type-check .astro files
+
+## Goal
+
+`just check` and CI type-check the `.astro` files under `src/`, which have never
+been checked: `check` has always been `biome ci && tsc --noEmit`.
+
+## Plan
+
+- Use [@astrojs/ts-content-mapper](https://github.com/withastro/astro/tree/main/packages/language-tools/ts-content-mapper)
+  with plain `tsc` (`contentMappers` in `tsconfig.json`, `--runExternalCode`).
+  It needs TypeScript 7.1.
+- Decided: adopt on the TypeScript 7.1 beta now rather than wait for stable,
+  then move to 7.1 stable when it ships.
+- Don't bring back `astro check` on TypeScript 6; it refuses TypeScript 7 and
+  the mapper is Astro's intended path.
+- Watch for [withastro/astro#18471](https://github.com/withastro/astro/issues/18471)
+  (reported on the `strictest` preset; this repo extends `strict`) and for Solid
+  JSX inside `.astro` files. Fix real errors the existing files surface in the
+  same PR.
+- MDX stays unchecked; the mapper only covers `.astro`.
diff --git a/quest/m0/biome-local.md b/quest/m0/biome-local.md
new file mode 100644
index 0000000..37268eb
--- /dev/null
+++ b/quest/m0/biome-local.md
@@ -0,0 +1,14 @@
+# [XS] Biome passes with Claude Code's local files
+
+## Goal
+
+`just check` passes on a checkout where Claude Code has written its per-user
+`.claude/settings.local.json`, and Biome stops printing warnings for files it
+cannot handle.
+
+## Plan
+
+- Gitignore `.claude/settings.local.json`. It is untracked today, so Biome
+  formats it and fails.
+- Drop Markdown from Biome's `files.includes`. Biome has no Markdown handler, so
+  every tracked `SKILL.md` prints a `files/missingHandler` warning.
diff --git a/quest/m0/lean-agents-md.md b/quest/m0/lean-agents-md.md
new file mode 100644
index 0000000..02047c8
--- /dev/null
+++ b/quest/m0/lean-agents-md.md
@@ -0,0 +1,20 @@
+# [S] Lean AGENTS.md
+
+## Goal
+
+AGENTS.md holds only the rules and conventions that steer agents, in the shape
+of [moq-dev/moq's root AGENTS.md](https://github.com/moq-dev/moq/blob/main/AGENTS.md).
+The repository description leaves it: the site table, command list, tech stack
+and version pins, architecture, URL scheme, deployment, and tips. Stale facts
+like the Bun version stop drifting because they are no longer written down.
+
+## Plan
+
+- Delete rather than relocate. The README already explains the three sites and
+  the URL scheme, and the two easy-to-break pitfalls are comments next to the
+  code (`sites/*/wrangler.jsonc`, `sites/lib/worker.ts`). If something
+  load-bearing turns out to be missing, add it as a comment beside that code.
+- The Bun pin-sync rule goes too. Make the flake's Bun assertion failure name
+  all three pins (nixpkgs, `packageManager` in `package.json`, the `Dockerfile`
+  base image), so the guidance appears exactly when CI catches the drift.
+- Read `PROMPTING.md` first. `CLAUDE.md` is a symlink to `AGENTS.md`.