diff --git a/CLAUDE.md b/CLAUDE.md
index d1a5c58..a0e8845 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -60,7 +60,7 @@ hardcode any hex values outside the token definitions.
 
 ## Pattern data
 
-15 patterns across 7 sections. All defined in the `PATTERNS` array in
+15 patterns across 8 sections. All defined in the `PATTERNS` array in
 `index.html`. Fields per pattern:
 
 ```js
@@ -95,6 +95,23 @@ as a dashed group box containing one node per `members` entry — `parallel`
 draws solid fan-out/fan-in edges (AND semantics), `branch` draws dashed
 edges (exclusive-OR / "choose one" semantics).
 
+### Statefulness tooltips
+
+`STATEFULNESS_INFO` (in `index.html`, alongside `PATTERNS`) maps each
+`statefulness` value to a one-sentence explanation, shown as a hover/focus
+tooltip on the "At a glance" panel's Statefulness row. Every distinct
+`statefulness` value used in `PATTERNS` must have an entry here —
+`scripts/validate-patterns.js` enforces this.
+
+### Deep dive button
+
+Each expanded card has a "Deep dive" button (`copyDeepDive` /
+`deepDivePrompt` in `index.html`). It copies a prompt built from the
+pattern's name, description, flow, and common uses to the clipboard
+(for pasting into a separate Claude conversation), and briefly shows
+"Copied ✓" on the button as feedback. It does not call any API or
+navigate away — the site has no backend.
+
 ---
 
 ## Export targets & tasks for Claude Code
@@ -140,6 +157,8 @@ ai-agent-patterns/
 ├── index.html          ← main interactive site (source of truth)
 ├── CLAUDE.md           ← this file
 ├── README.md           ← to be generated by Claude Code
+├── docs/
+│   └── preview.png      ← committed screenshot for README (exports/ is gitignored)
 ├── exports/
 │   ├── linkedin-all.png
 │   ├── linkedin-single.png
diff --git a/README.md b/README.md
index 0db93f9..65d1623 100644
--- a/README.md
+++ b/README.md
@@ -7,16 +7,21 @@
 An interactive reference of AI agent design patterns — single-agent and
 multi-agent architectures — covering 15 patterns across 8 sections. Built as
 a single self-contained `index.html` with no build step and no external
-dependencies. Click any card to expand it and see its description, common
-uses, and at-a-glance metadata (complexity, agent count, loop type,
-statefulness).
+dependencies. Click any card to expand it and see a colored flow diagram,
+its description, common uses, and at-a-glance metadata (complexity, agent
+count, loop type, statefulness — hover any statefulness value for an
+explanation). The "Deep dive" button copies a ready-to-paste prompt
+(pattern name, description, flow, and common uses) to your clipboard for
+following up in a Claude conversation.
 
 The same `index.html` is the source of truth for every other export format
 in this repo (LinkedIn images, PPTX slides, PDF) — all of them render
 directly from the `PATTERNS` array defined in that file.
 
-![Site preview](exports/linkedin-all.png)
-<!-- Generated by `npm run export:images` — run it once to populate this screenshot. -->
+![Site preview](docs/preview.png)
+<!-- Static snapshot for GitHub's README renderer. Regenerate with
+     `npm run export:images && cp exports/linkedin-all.png docs/preview.png`
+     after a visual change to the site. -->
 
 ## Patterns
 
@@ -60,10 +65,15 @@ headless browser) so there is only ever one copy of the content.
 npm install
 npx playwright install chromium
 
-npm run export:images   # exports/linkedin-{all,single,multi}.png + exports/card-{slug}.png
+npm run validate         # checks PATTERNS against the schema in CLAUDE.md
+npm run export:images    # exports/linkedin-{all,single,multi}.png + exports/card-{slug}.png
 npm run export:pptx      # exports/ai-agent-patterns.pptx
 ```
 
+`npm run validate` and both export scripts also run on every pull request
+via `.github/workflows/ci.yml`, so a malformed pattern or a renderer crash
+is caught before merge.
+
 ## Project structure
 
 ```
@@ -71,16 +81,21 @@ ai-agent-patterns/
 ├── index.html                       ← main interactive site (source of truth)
 ├── CLAUDE.md                        ← project spec for Claude Code
 ├── README.md
-├── exports/                         ← generated by the scripts below
+├── docs/
+│   └── preview.png                  ← committed screenshot for this README
+├── exports/                         ← generated by the scripts below, gitignored
 │   ├── linkedin-all.png
 │   ├── linkedin-single.png
 │   ├── linkedin-multi.png
 │   ├── card-*.png
 │   └── ai-agent-patterns.pptx
 ├── scripts/
+│   ├── validate-patterns.js
 │   ├── export-images.js
 │   └── export-pptx.js
-└── .github/workflows/deploy.yml     ← GitHub Pages deploy action
+└── .github/workflows/
+    ├── deploy.yml                  ← GitHub Pages deploy action
+    └── ci.yml                      ← PR validation (schema + export smoke test)
 ```
 
 ## License
diff --git a/docs/preview.png b/docs/preview.png
new file mode 100644
index 0000000..febfbf6
Binary files /dev/null and b/docs/preview.png differ