Collectors · Developers & tech

npm registry API in Python

Search the npm registry — version, description, license, downloads, quality score, links. One POST from Python with query, rows back as JSON with 21 fields, $0.0003 per delivered package. No proxies or parsers to maintain.

Get an API key See the collector

A Python requests snippet that posts { — A Python requests call to the npm_packages collector returns one dict per package, at $0.0003 each.

First call

Install, call, read the rows.

pip install requests

The only dependency.

import os, requests

r = requests.post(
    "https://api.quanticdata.io/v1/scraper/collectors/npm_packages/run",
    headers={"Authorization": f"Bearer {os.environ['QD_API_KEY']}"},
    json={
        "query": "react state management",
        "max_results": 20,
    },
    timeout=120,
)
r.raise_for_status()
run = r.json()["payload"]
print(run["count"], "rows,", run["cost"]["usd"], "USD")
for row in run["results"]:
    print(row.get("name"), row.get("version"), row.get("description"), row.get("keywords"))

Python: one npm package search run (Ricerca), printing name, version, description, keywords

The key comes from an environment variable, never from the code. The run answers in the same request when it finishes in time; payload.results holds the rows and payload.cost what they cost.

Request parameters

What the collector takes.

Input of the npm package search collector
Parameter	Type	Required	Meaning
`query`	string	yes	Search text — package name, keyword, author:… or scope.
`max_results`	integer	no (default 20)	How many packages to deliver at most (1–100). You pay only for delivered packages.

Response fields

21 fields per package.

Fields of each row (package)
Field	Type	What it holds
`rank`	integer	1-based position.
`name`	string	Package name.
`version`	string, nullable	Latest version.
`description`	string, nullable	Package description.
`keywords`	string[]	Declared keywords.
`license`	string, nullable	License (SPDX).
`publisher`	string, nullable	Last publisher.
`homepage`	string, nullable	Homepage URL.
`repository`	string, nullable	Repository URL.
`npm_url`	string	npmjs.com package URL.
`published_at`	string, nullable	Last publish (ISO 8601).
`quality_score`	number, nullable	Registry quality score 0–1.
`downloads_weekly`	integer, nullable	Weekly downloads.
`downloads_monthly`	integer, nullable	Monthly downloads.
`dependents`	integer, nullable	Dependent packages.
`maintainers`	string[]	Maintainer usernames.
`bugs_url`	string, nullable	Issue tracker URL.
`popularity_score`	number, nullable	Registry popularity score 0–1.
`maintenance_score`	number, nullable	Registry maintenance score 0–1.
`search_score`	number, nullable	Relevance score of this result for the query.
`insecure`	boolean	Flagged insecure by the registry.

Add ?format=csv to the runs endpoint to get the same rows as CSV.

Long runs

Run in the background, then poll.

A run that needs more time can go to the background: send "async": true, get 202 with the run id, and poll the runs endpoint until the status is done. Reading a run is free.

import os, time, requests

H = {"Authorization": f"Bearer {os.environ['QD_API_KEY']}"}
r = requests.post("https://api.quanticdata.io/v1/scraper/collectors/npm_packages/run", headers=H,
                  json={**{"query":"react state management","max_results":20}, "async": True}, timeout=30)
run_id = r.json()["payload"]["run_id"]
while True:
    run = requests.get(f"https://api.quanticdata.io/v1/scraper/collectors/runs/{run_id}", headers=H, timeout=30).json()["payload"]
    if run["status"] in ("done", "failed"):
        break
    time.sleep(5)
print(run["status"], run["count"])

Python: background run and polling

Errors

What can come back, and what is billed.

Collector run errors
Status	Meaning	Billed
`400`	The input does not match the collector (`payload.errors`)	No
`401`	Missing or wrong API key	No
`402`	Balance and free credit do not cover the run: top up	No
`422`	The input can never resolve; retrying the same input cannot help	No
`424`	The run failed at the source (blocked, timed out, layout changed); safe to retry	No
`429`	Rate limit or a per-account brake; wait for `Retry-After`	No

Only delivered rows are billed: a run that delivers nothing costs nothing.

Price

$0.0003 per delivered package.

What npm package search rows cost at list price
Rows	Cost
1	$0.0003
1,000	$0.30
10,000	$3.00

Up to 100 packages per run; split larger jobs into several runs. The $2 free credit every month covers about 6,666 packages. No subscription; paid tiers lower the unit price. All collector prices: collector pricing.

Before you run it

Questions developers ask

Is there a free npm package search API?

Every account gets $2 of free usage each month, about 6,666 packages of this collector at $0.0003 each, with no card.

Do I have to handle proxies, retries or blocks?

No. The collector runs on our network and handles them; a run blocked at the source returns 424 and is not billed.

How many rows can one run return?

Up to 100 packages per run (the max_results input, where the collector has one).

Can an AI agent run it?

Yes: the MCP server exposes it as the run_collector tool, with the same input and price. See the MCP server.

Run it on the free credit.

Create an API key, export it as QD_API_KEY and run the example. $0.0003 per delivered package, no subscription.

Get an API key npm registry API