npm-package-comparator
npm Package Comparator
Compare any set of npm packages side by side using live data from npm, GitHub, Bundlephobia, and Snyk — then give a clear recommendation based on what you actually need.
Pre-flight Check (REQUIRED)
Before making any TinyFish call, always run BOTH checks:
1. CLI installed?
which tinyfish && tinyfish --version || echo "TINYFISH_CLI_NOT_INSTALLED"
If not installed, stop and tell the user:
Install the TinyFish CLI:
npm install -g @tiny-fish/cli
2. Authenticated?
tinyfish auth status
If not authenticated, stop and tell the user:
You need a TinyFish API key. Get one at: https://agent.tinyfish.ai/api-keys
Then authenticate:
tinyfish auth login
Do NOT proceed until both checks pass.
Step 1 — Gather inputs
You need:
- Package names — 2 to 4 packages to compare (e.g.
zustand,jotai,redux) - Use case (optional but improves recommendation) — e.g. "small React app", "large enterprise codebase", "need SSR support"
If the user hasn't specified a use case, ask:
"What are you building with it? (e.g. small side project, large team codebase, performance-critical app)"
If they don't know, proceed without it and give a general recommendation.
Step 2 — Parallel data fetch
For each package, fire agents across npm, GitHub, Bundlephobia, and Snyk simultaneously. Run ALL agents for ALL packages in parallel — one agent per package per source.
# ── For each PACKAGE, run all 4 agents in parallel ───────────
# npm stats
tinyfish agent run \
--url "https://www.npmjs.com/package/{PACKAGE}" \
"You are on the npm page for the package {PACKAGE}.
Extract:
- current version
- weekly downloads (exact number shown)
- total downloads if shown
- last publish date
- license
- number of dependencies
- TypeScript support (yes/no — check if types are listed)
- maintainers count
- repository URL
STRICT RULES:
- Do NOT click any links
- Read only what is visible on this page
- If a field is not shown, return null
Return JSON: {package, version, weekly_downloads, last_published, license, dependency_count, typescript_support, maintainer_count, repo_url}" \
--sync > /tmp/npm_{PACKAGE_SAFE}.json &
# GitHub stats
tinyfish agent run \
--url "https://github.com/{OWNER}/{REPO}" \
"You are on the GitHub repository page for {PACKAGE}.
Extract:
- star count
- fork count
- open issues count
- last commit date
- number of contributors (from sidebar or Insights)
- latest release tag and date
- whether the repo is actively maintained (check: last commit within 6 months)
STRICT RULES:
- Do NOT click any tabs or links
- Read only what is visible on the main repo page
Return JSON: {package, stars, forks, open_issues, last_commit, contributors, latest_release, latest_release_date, is_active}" \
--sync > /tmp/gh_{PACKAGE_SAFE}.json &
# Bundle size
tinyfish agent run \
--url "https://bundlephobia.com/package/{PACKAGE}" \
"You are on the Bundlephobia page for {PACKAGE}.
Extract:
- minified size (in KB)
- minified + gzipped size (in KB)
- download time on slow 3G (if shown)
- tree-shakeable (yes/no)
- side-effect free (yes/no)
STRICT RULES:
- Do NOT click any links
- Read only what is visible on this page
- If the page hasn't loaded sizes yet, note it
Return JSON: {package, minified_kb, gzipped_kb, tree_shakeable, side_effect_free}" \
--sync > /tmp/bp_{PACKAGE_SAFE}.json &
# Known vulnerabilities
tinyfish agent run \
--url "https://security.snyk.io/package/npm/{PACKAGE}" \
"You are on the Snyk security page for the npm package {PACKAGE}.
Extract:
- total number of known vulnerabilities
- number by severity: critical, high, medium, low
- most recent vulnerability title and date (if shown)
STRICT RULES:
- Do NOT click any vulnerability links
- Read only the summary visible on this page
- If the page shows 'no vulnerabilities', return {total: 0}
Return JSON: {package, total_vulns, critical, high, medium, low, latest_vuln_title, latest_vuln_date}" \
--sync > /tmp/snyk_{PACKAGE_SAFE}.json &
# Repeat the above 4 agents for each additional package
# All backgrounded with & — fire everything at once then:
wait
# Collect all results
for p in {PACKAGE_LIST}; do
echo "=== $p ==="
cat /tmp/npm_${p}.json
cat /tmp/gh_${p}.json
cat /tmp/bp_${p}.json
cat /tmp/snyk_${p}.json
done
Before running, replace:
{PACKAGE}— exact npm package name e.g.zustand{PACKAGE_SAFE}— safe filename version e.g.zustand{OWNER}/{REPO}— GitHub repo e.g.pmndrs/zustand{PACKAGE_LIST}— space-separated list of all packages
Use your knowledge to find the correct GitHub repo for well-known packages. For unknown packages, check the repository field on their npm page first.
Step 3 — Synthesize comparison
Combine all data into a side-by-side comparison.
## Package Comparison: {PACKAGE_1} vs {PACKAGE_2} vs ...
*Data fetched live — {date}*
---
### 📊 At a Glance
| | {pkg1} | {pkg2} | {pkg3} |
|---|---|---|---|
| **Version** | {v} | {v} | {v} |
| **Weekly Downloads** | {n} | {n} | {n} |
| **GitHub Stars** | {n} | {n} | {n} |
| **Bundle (gzipped)** | {n}kb | {n}kb | {n}kb |
| **Tree-shakeable** | ✅/❌ | ✅/❌ | ✅/❌ |
| **TypeScript** | ✅/❌ | ✅/❌ | ✅/❌ |
| **Last Published** | {date} | {date} | {date} |
| **Known Vulns** | {n} | {n} | {n} |
| **License** | {l} | {l} | {l} |
---
### 📈 Popularity & Health
{2-3 sentences comparing download trends, GitHub activity, and community size}
---
### 📦 Bundle Size
{Comparison of bundle impact — important for frontend packages}
{Flag if any package is significantly larger than alternatives}
---
### 🔒 Security
{Note any packages with known vulnerabilities}
{If all clean: "No known vulnerabilities found for any of these packages."}
---
### ⚙️ Maintenance
{Compare last commit dates, contributor counts, release cadence}
{Flag any package that looks abandoned (no commits in 12+ months)}
---
### 🎯 Recommendation
{Use case}: {user's stated use case or "general use"}
**Best pick: {PACKAGE}**
{2-3 sentences explaining why this package wins for this use case, and what trade-offs you're making}
**When to pick {PACKAGE_2} instead:**
{1-2 sentences on when the runner-up is the better choice}
**Avoid {PACKAGE_3} if:**
{Any specific reasons to avoid a package in certain contexts}
Edge Cases
- Package not on npm — check if it's a GitHub-only package and scrape the repo directly
- Bundlephobia doesn't have it — note "bundle size unavailable" and skip that row
- GitHub repo not found from npm page — search
https://github.com/search?q={PACKAGE}&type=repositoriesto find the canonical repo - One of the packages is deprecated — flag it clearly at the top of the comparison: "⚠️ {package} is deprecated — the maintainers recommend {replacement}"
- Comparing more than 4 packages — ask the user to narrow to their top 3, as more becomes hard to compare meaningfully
- Packages serve slightly different purposes — note the distinction upfront before comparing (e.g. "react-query handles server state, zustand handles client state — you may actually need both")