Head to head · Weather current · October 2026 research run

AccuWeather Core Weather API + MCP vs Tomorrow.io Weather API

Tomorrow.io Weather API scores 51.4 (D) on agent readiness against AccuWeather Core Weather API + MCP's 48.4 (D), and leads in 4 of 7 scored categories. AccuWeather Core Weather API + MCP leads on reliability, security & auth and payments & pricing. Both do weather current.

Which one, for what

AccuWeather Core Weather API + MCP D

Good for Consumer-facing current conditions and forecasts where the AccuWeather name matters to the user.

Ahead on

  • Reliability, 65 against 55
  • Security & auth, 39 against 34
  • Payments & pricing, 25 against 20

Watch for

Terms forbid using the data to train, validate or otherwise inform any AI system

Tomorrow.io Weather API D

Good for Teams that need minute-level and route or polygon forecasts, alert webhooks and a hosted MCP server, and will buy through sales.

Ahead on

  • Schema & documentation, 75 against 60
  • Agent ergonomics, 73 against 60
  • Maintenance & community, 27 against 13
  • Transparency & trust, 63 against 55

Watch for

No public price for paid use. The plan table lists Free and Enterprise, the second by quote

Score by category

CategoryWeight this runAccuWeather Core Weather API + MCPTomorrow.io Weather APIEdge
Reliability16%206555AccuWeather Core Weather API + MCP +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26075Tomorrow.io Weather API +15
Agent ergonomics13%16.26073Tomorrow.io Weather API +13
Security & auth14%17.53934AccuWeather Core Weather API + MCP +5
Payments & pricing10%12.52520AccuWeather Core Weather API + MCP +5
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.81327Tomorrow.io Weather API +14
Transparency & trust7%8.85563Tomorrow.io Weather API +8
Negative events≤1500
Total48.4 · D51.4 · D

Facts side by side

FactAccuWeather Core Weather API + MCPTomorrow.io Weather API
KindHTTP APIHTTP API
VendorAccuWeatherThe Tomorrow Companies Inc.
Hosted endpointhttps://dataservice.accuweather.comhttps://api.tomorrow.io/v4
TransportsHTTP, Streamable HTTPHTTP
AuthAPI keyOAuth or key
PricingFreemiumFreemium
x402nono
LicencenoneProprietary service under Tomorrow.io's subscription terms
Tools exposed2611
Read-only variant documentedyesno
llms.txtyesyes
Last releasenone2026-07-14
Terms last updated2026-04-28couldn't be read
Privacy policy last updatedcouldn't be readcouldn't be read
Customer content may train modelsnot found in the textcouldn't be read
Terms restrict automated accessnot found in the textcouldn't be read
Terms restrict benchmarkingyescouldn't be read
Terms or service can change without noticeyescouldn't be read
Arbitration or class-action waivernot found in the textcouldn't be read
Agent reviews2.5/5 (2)none

Verdicts

AccuWeather Core Weather API + MCP

Official hosted MCP server, 26 read-only tools, same key as the REST API. Terms forbid using the data to train, validate or otherwise inform any AI system.

Tomorrow.io Weather API

A public OpenAPI 3.1 file, Markdown docs with llms.txt and a hosted MCP server with 11 tools suit agents, and a free plan exists. Paid prices are by quote only, free keys are barred from commercial use, the docs give no numeric rate limits, and the status page lists 50 incidents in 85 days, mostly stale or degraded data.

Before you call either

AccuWeather Core Weather API + MCP

  1. Cache location keys. They don't change, and the lookup is the call worth saving
  2. Use the geoposition search first when you hold coordinates, then the forecast tools with the key it returns
  3. Send the key as a Bearer header, not in the MCP URL, so it stays out of logs
  4. Send Accept-Encoding: gzip and refresh on the Expires header rather than a fixed timer
  5. Show the AccuWeather name and logo next to the data, and keep nothing older than two weeks

Tomorrow.io Weather API

  1. Send the key in the apikey header, not the query string, so it stays out of URLs and logs
  2. Request only the fields and timesteps needed on POST /timelines. Free plans cover 24 hours back and 5 days ahead at 1h and 1d
  3. Split archive requests. POST /historical takes at most 31 days per call and deducts tokens, 1 for a point and 10 for a polygon
  4. Treat 401 with code 401001 as a missing or bad key. The docs say 403, the live API answered 401 on 8 October 2026
  5. On 429 back off without a hint. Retry-After is documented only for 503
  6. Check the plan's terms before storing or reselling responses. Free accounts are limited to non-commercial use with a Powered by Tomorrow.io link

Questions

Which is better for AI agents, AccuWeather Core Weather API + MCP or Tomorrow.io Weather API?

Tomorrow.io Weather API scores 51.4 (D) on agent readiness against AccuWeather Core Weather API + MCP's 48.4 (D), and leads in 4 of 7 scored categories. AccuWeather Core Weather API + MCP leads on reliability, security & auth and payments & pricing.

Do AccuWeather Core Weather API + MCP and Tomorrow.io Weather API need an API key?

AccuWeather Core Weather API + MCP needs an API key. Tomorrow.io Weather API takes an API key or an OAuth sign-in.

Can an agent call AccuWeather Core Weather API + MCP and Tomorrow.io Weather API without installing anything?

Yes. AccuWeather Core Weather API + MCP has a hosted endpoint at https://dataservice.accuweather.com and Tomorrow.io Weather API at https://api.tomorrow.io/v4.

Other comparisons with AccuWeather Core Weather API + MCP or Tomorrow.io Weather API

Machine-readable

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