| 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:
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:
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:
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:
---
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
