---
name: cp-skill-snapshot-web
description: Snapshot any URL into kb/sources/. Routes by URL type — GitHub issues/PRs via gh API, X/Twitter via xdk, PDFs via download+Read, web pages via WebFetch. One skill, URL in, markdown snapshot out. Triggers on "/cp-skill-snapshot-web", "/cp-skill-snapshot-web [url]".
type: kb/types/instruction.md
user-invocable: true
allowed-tools: Read, Write, Grep, Glob, WebFetch, Bash
context: fork
model: sonnet
argument-hint: "[url] — URL to snapshot (web page, PDF, GitHub issue/PR, or X/Twitter post)"
---
## EXECUTE NOW
**Target: $ARGUMENTS**
If no URL provided, ask the user for one.
If URL provided, start Step 1 immediately.
**START NOW.**
---
## Step 1: Check for Duplicates
Use Grep to search for the URL in existing `.md` files in `kb/sources/`. If found, tell the user and stop:
> Already snapshotted: kb/sources/{filename}
## Step 2: Route by URL Type
Detect the URL type and branch:
- **GitHub issue/PR** (`github.com/.../issues/N` or `github.com/.../pull/N`) → **Step 2a**
- **X/Twitter** (`x.com/.../status/...` or `twitter.com/.../status/...`) → **Step 2b**
- **PDF** (URL ends in `.pdf`, or `arxiv.org/pdf/`) → **Step 2c**
- **Everything else** → **Step 2d**
### Step 2a: GitHub Issue/PR
Run:
```bash
commonplace-github-snapshot "{url}"
```
Parse the "Snapshot saved:" line from the output to get the file path. Tell the user and stop — the script handles metadata, formatting, and saving.
### Step 2b: X/Twitter Post
Run:
```bash
commonplace-x-snapshot "{url}"
```
Parse the "Snapshot saved:" line from the output to get the file path. Tell the user and stop — the script handles metadata, formatting, and saving.
### Step 2c: Fetch PDF
Download the PDF to a temporary file:
```bash
curl -sL -o /tmp/snapshot_download.pdf "{url}"
```
Then use the Read tool to read the PDF:
- For short papers (< 20 pages): `Read(file_path="/tmp/snapshot_download.pdf")`
- For longer papers: read in chunks using the `pages` parameter (max 20 pages per request), e.g. `pages: "1-20"`, then `pages: "21-40"`, etc.
Set `capture_method` to `pdf-read` and go to **Step 4**.
### Step 2d: Fetch Web Page
Use WebFetch with this prompt:
> Extract the main article/post content from this page as clean markdown.
> Return ONLY the content — no navigation, sidebars, ads, cookie banners, or boilerplate.
> Preserve: headings, block quotes, code blocks, links, lists, emphasis.
> For blog posts: include the author name, publication date, and tags if visible.
> If the page has no extractable content (login wall, JS-only, error page), say "NO_CONTENT:" followed by a brief reason.
Set `capture_method` to `web-fetch` and go to **Step 4**.
## Step 3: Handle Failures
If any fetch method fails (WebFetch NO_CONTENT, curl error, script error):
- Tell the user what happened
- Suggest they paste the content manually: "You can paste the text and I'll save it as a snapshot"
- Stop
## Step 4: Determine Metadata
**(Only for PDF and web page paths — GitHub and X scripts handle their own metadata.)**
From the fetched content and URL, determine:
- **title**: The article/post title. Use the first H1 if present, otherwise derive from content.
- **author**: If identifiable from the content or URL (e.g. simonwillison.net → Simon Willison)
- **genre**: the source's genre per the snapshot type spec's vocabulary. The snapshot type is whatever `kb/sources/COLLECTION.md`'s Types menu lists for verbatim captures — `kb/sources/types/snapshot.md` in the shipped default; a KB may declare its own. This is a surface judgment of what kind of document the source is as evidence — ingestion may correct it later. Prefer a value from the type spec's list; a value outside it validates with a warning, so extend only for a genuinely new evidential kind, not a container.
- **description**: One sentence describing what makes this source worth retrieving. Not a summary — a retrieval filter (e.g. "Anthropic CEO's capability-timeline predictions — verifiable domains get confident timelines, unverifiable ones get hedged"). Focus on what distinguishes this source from others on the same topic.
- **slug**: Lowercase, hyphenated, max 70 chars. Derived from title. Example: `simon-willison-karpathy-claws`
For academic papers: prefer the paper title over any page title, and extract authors from the author list.
## Step 5: Write the Snapshot
Save to `kb/sources/{slug}.md` with this format:
```markdown
---
source: {url}
description: {description}
captured: {YYYY-MM-DD}
capture: {capture_method}
genre: {genre}
type: {snapshot type path from the Types menu, default kb/sources/types/snapshot.md}
---
# {title}
Author: {author}
Source: {url}
Date: {publication date if known}
{extracted content}
```
For PDFs: convert the read content to clean markdown. Preserve section structure, tables, and lists. Drop page numbers, headers/footers, and layout artifacts.
Also tell the user where it was saved and show a 1-2 line preview.
## Critical Constraints
**Never:**
- Fabricate or hallucinate content not on the page
- Add analysis or commentary — this is capture, not ingestion
- Modify the extracted content beyond cleaning HTML/PDF artifacts
- Save to any directory other than `kb/sources/`
- Install software — if a required tool is missing, bail with an error telling the user what to install
**Always:**
- Preserve the author's structure (headings, quotes, lists)
- Include the source URL in frontmatter
- Use today's date for `captured`
- Check for duplicates before fetching
- Clean up temporary PDF files after reading