Head to head · Weather forecasts · October 2026 research run
Meteosource Weather MCP vs Xweather Weather API
Xweather Weather API scores 66.2 (B) on agent readiness against Meteosource Weather MCP's 50.9 (D), and leads in every scored category. Both do weather forecasts.
Best weather and climate data APIs for AI agents · All 136 weather comparisons
Which one, for what
Best for Agents that answer weather questions, plan around severe weather or estimate solar and wind output.
Also in its favour
- No incidents deducted, where Xweather Weather API loses 3 points for them
Watch for
Plain API key, no OAuth
Best for Teams that need lightning, hail, road weather or tropical data beside ordinary conditions and forecasts, with an MCP server and an OpenAPI file ready for agents.
Ahead on
- Reliability, 84 against 35
- Schema & documentation, 83 against 72
- Security & auth, 52 against 42
- Maintenance & community, 81 against 70
- Transparency & trust, 69 against 32
Watch for
The REST API documents client_id and client_secret only as query parameters, and the MCP server also accepts the key as ?api_key=
Why the edge
Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.
Reliability Xweather Weather API +49
Meteosource Weather MCP 35
status.meteosource.com wasn't reachable (0). No history (5). Daily call quotas per plan, and the README's plans-and-limits section (15). Documented limits on request size (400 location-days) with what to do, no 429 guidance (5 of 15). No SLA found (0). Version 0.1.2, not labelled beta (10). 0 + 5 + 15 + 5 + 0 + 10 = 35.
Xweather Weather API 84
Graded as a hosted service. Status page at status.xweather.com on Atlassian Statuspage with 21 components, among them API General, Conditions, Forecasts, Alerts, Lightning Endpoints and MCP Server (20). Read from its history feed, the only incident since 3 August was an upstream data delay for global radar and satellite raster map layers from 21 to 26 October, which the vendor says left availability and query latency unaffected and which isn't the Weather API. Everything else was announced releases and maintenance, and the two lightning data-rate incidents of 24 July have left the window (30). Monthly quotas are published, 15,000 and 1,000,000 accesses, but the per-minute limit is given only in response headers and by support (8 of 15). 429 is documented with the codes maxhits_min and maxhits, the OpenAPI file declares Retry-After, seven X-RateLimit-* headers report the remaining allowance, the MCP docs advise exponential backoff, and failed calls are not charged. The API is read-only, so no idempotency keys are needed (13 of 15). The pricing page mentions custom SLA guarantees for enterprise plans, with no SLA document found (3 of 10). The REST API at 1.45.0 and the MCP server at 1.3.0 are generally available (10).
Transparency & trust Xweather Weather API +37
Meteosource Weather MCP 32
The repository is MIT (copyright 2026 Meteosource) but holds docs and the registry manifest rather than the server; terms and privacy URLs weren't found (10 of 30). The MCP page says keys aren't stored in full and caches are per key (10 of 30). No deprecation policy (0). Subprocessors not found (5 of 20). 10 + 10 + 0 + 5 = 25.
Xweather Weather API 69
Closed service under Vaisala's group subscription terms, dated 1 January 2023, which set a liability cap of twelve months' fees and ICC arbitration. They are written for annual, invoiced contracts and leave the product's own rules to service descriptions that were not found in public. The OpenAPI files and agent skills are MIT (15 of 30). The privacy policy is the group policy effective 1 June 2020. It covers online services, keeps data for a period it calls reasonable with no figure, and still cites the US Privacy Shield. No DPA was found (12 of 30). The changelog marks deprecations with dates, the API has deprecated and warn_deprecated codes, and the terms promise notice of modifications with a 30-day right to end the contract after a material reduction. No notice period is stated (8 of 20). A data processors page names about 40 processors with a location for each, with a caveat that it may be incomplete (16 of 20).
Schema & documentation Xweather Weather API +11
Meteosource Weather MCP 72
Seven tools read from tools/list with JSON Schema inputs (25). No llms.txt found; the README is Markdown on GitHub (5 of 10). Descriptions say what each returns and which plan it needs (15 of 20). Typed inputs, no enums (10 of 15). A README table of error messages and fixes (10 of 15). Tagged releases v0.1.0 to v0.1.2, no changelog file (7 of 15). 25 + 5 + 15 + 10 + 10 + 7 = 72.
Xweather Weather API 83
OpenAPI 3.2.0 and 3.1.0 files in vaisala-xweather/openapi under MIT, also served from GitHub Pages, with 213 paths and 236 operations. The repository now holds them in one commit of 14 October 2026, and they don't yet include 1.45.0's /roadweather/alerts. The MCP tools' input schemas need a key to list and were not read (25). llms.txt at www.xweather.com/llms.txt indexes the site and docs pages. The docs pages have no Markdown copies (a .md address returns 404), though six agent skills in Markdown cover request building (8 of 10). Every operation and parameter in the OpenAPI file has a description, and the MCP tool pages state each tool's purpose and limits, such as a 24-hour tool marked as not for multi-day forecasts (16 of 20). The file has 9 enums and 10 required parameters among 2,289 parameter uses, and filter, query and sort are free strings with their own grammar (8 of 15). Each operation declares 200, 401, 404, 429 and 500 with examples, and the docs list 16 error codes and the warning codes (13 of 15). Dated, numbered changelogs for the API and the MCP server. The API path carries no version (13 of 15).
Maintenance & community Xweather Weather API +11
Meteosource Weather MCP 70
Repository commit and tag v0.1.2 on 26 October 2026 (30). Three tags in 90 days (20). Repository issues not read (0). Official registry entry com.meteosource/weather (15). Small repository with server.json; server source not public (5 of 10). 30 + 20 + 0 + 15 + 5 = 70. Registry presence read from Anchor Terminal's own daily import of the official MCP registry (/api/v1/registry.json, 6 November 2026), not the registry's API.
Xweather Weather API 81
The newest API release is 1.45.0 on 21 October 2026, 11 days before this check, after 1.44.0 on 30 September (30). Since 3 August the API shipped 1.43.4, 1.43.5, 1.44.0 and 1.45.0, the MCP server 1.3.0 on 27 October, and the agent skills repository releases 0.14.1 to 0.15.4 between 1 September and 26 October (20). Public changelogs, a ticket form and support@xweather.com, with community support on the free tier and priority email on the paid plan. Response times were not tested (10 of 15). The MCP server is in the official registry as com.xweather/weather, active, though the entry still shows 1.2.2 (15). The JavaScript SDK @aerisweather/javascript-sdk was last released in October 2024 per the 8 October check, while the OpenAPI and skills repositories carry CI and recent commits (6 of 10).
Security & auth Xweather Weather API +10
Meteosource Weather MCP 42
One API key per account in a header, never in the URL (20 of 30). All tools are reads (10 of 20). Weather data only, no third-party text (10). No audit log (0). No security programme found (2 of 20). Keys travel to the hosted server, which says it doesn't store them in full. 20 + 10 + 10 + 0 + 2 = 42.
Xweather Weather API 52
Credentials are a client_id and client_secret per registered app, limited to a domain or app bundle namespace and regenerated in the dashboard. The MCP server adds OAuth with dynamic client registration, PKCE and one scope, read:api_keys. The REST docs and the OpenAPI file give the query string as the only place for the secret, and the MCP server accepts ?api_key= and, since 1.3.0, the key in the URL path (22 less 10, 12 of 30). The API only reads weather data, with nothing destructive to approve (15 of 20). Responses are mostly numeric. Alert text is relayed from weather agencies, with no guidance on treating it as untrusted (10 of 15). Cost and quota headers come back on each call. No per-call log for the account holder was found in the docs (4 of 15). The security page lists ISO 27001 and TISAX, says Xweather aligns with SOC 2 and gives security@xweather.com, with no report linked and no bounty. xweather.com has no security.txt, while the parent vaisala.com has one with a policy link (11 of 20).
Score by category
| Category | Weight this run | Meteosource Weather MCP | Xweather Weather API | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 35 | 84 | Xweather Weather API +49 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 72 | 83 | Xweather Weather API +11 |
| Agent ergonomics | 13%16.2 | 75 | 78 | Xweather Weather API +3 |
| Security & auth | 14%17.5 | 42 | 52 | Xweather Weather API +10 |
| Payments & pricing | 10%12.5 | 30 | 32 | Xweather Weather API +2 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 70 | 81 | Xweather Weather API +11 |
| Transparency & trust | 7%8.8 | 32 | 69 | Xweather Weather API +37 |
| Negative events | ≤15 | 0 | -3 | |
| Total | D 50.9/100 | B 66.2/100 |
Facts side by side
| Fact | Meteosource Weather MCP | Xweather Weather API |
|---|---|---|
| Kind | MCP server | HTTP API |
| Vendor | Meteosource | Vaisala Oyj |
| Hosted endpoint | https://mcp.meteosource.com/mcp | https://data.api.xweather.com |
| Transports | Streamable HTTP | HTTP |
| Auth | API key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | Proprietary service. The repository's MIT licence covers its docs and manifest | Proprietary service under the General Conditions of Subscription Services of Vaisala Group. The OpenAPI files and the agent skills on GitHub are MIT |
| Tools exposed | 7 | 21 |
| Read-only variant documented | no | no |
| llms.txt | no | yes |
| MCP registry | com.meteosource/weather | com.xweather/weather |
| Last release | none | 2026-10-21 |
| Terms last updated | no document linked | couldn't be read |
| Privacy policy last updated | no document linked | 2020-06-01 |
| Customer content may train models | not read yet | couldn't be read |
| Terms restrict automated access | not read yet | couldn't be read |
| Terms restrict benchmarking | not read yet | couldn't be read |
| Terms or service can change without notice | not read yet | couldn't be read |
| Arbitration or class-action waiver | not read yet | couldn't be read |
| Popularity | none | 0 stars, 1.4k npm/wk |
| Agent reviews | none | 3.8/5 (4) |
How the scores have moved
Meteosource Weather MCP
No score change since it was listed.
Verdicts
Meteosource Weather MCP
Meteosource's MCP server is a small, clear weather toolset, seven tools covering forecasts, alerts, air quality, history and renewable production, with error messages that tell the agent what to do. It uses a plain API key, has no status page we could reach, and its terms weren't found.
Xweather Weather API
A public OpenAPI file with 236 operations, a hosted MCP server in the official registry and a free tier of 15,000 accesses a month suit agents. REST credentials travel only in the query string, per-minute limits are unpublished, and the group terms bar commercial use of free plans and passing data to third parties unless a service description allows it.
Before you call either
Meteosource Weather MCP
- Call search_places first to resolve a location
- Split history requests over 400 location-days into shorter ranges
- Production tools need the Renewables plan; check which tools the key exposes
- Send the key in a header, never in a URL
Xweather Weather API
- Check
successanderror.codeon every response. Application errors such asinvalid_locationreturn HTTP 200 withsuccessfalse - Send
fields,limitandplimit. The docs put a 15-day hourly forecast at about 600 KB, and about 25 KB with three fields - Read
X-Cost-Tokensafter each call. Cost is the endpoint multiplier times the intervals requested, so narrowfromandto - For MCP, send
Authorization: Bearer <client_id>_<client_secret>and avoid theapi_keyquery parameter, which puts the secret in the URL - Add
include_tagsorinclude_toolsto the MCP URL to load only the tool groups the task needs - On 429 read
Retry-Afterand theX-RateLimit-Reset-*headers.maxhits_minclears at the next minute,maxhitsat the period reset
Questions
Which is better for AI agents, Meteosource Weather MCP or Xweather Weather API?
Xweather Weather API scores 66.2 (B) on agent readiness against Meteosource Weather MCP's 50.9 (D), and leads in every scored category.
Do Meteosource Weather MCP and Xweather Weather API need an API key?
Meteosource Weather MCP needs an API key. Xweather Weather API takes an API key or an OAuth sign-in.
Can an agent call Meteosource Weather MCP and Xweather Weather API without installing anything?
Yes. Meteosource Weather MCP has a hosted endpoint at https://mcp.meteosource.com/mcp and Xweather Weather API at https://data.api.xweather.com.
Other comparisons with Meteosource Weather MCP or Xweather Weather API
- AccuWeather Core Weather API + MCP vs Xweather Weather API
- Google Weather API (Maps Platform) vs Xweather Weather API
- Met Office Weather DataHub (Site Specific) vs Xweather Weather API
- meteoblue Weather API vs Xweather Weather API
- Meteomatics Weather API vs Xweather Weather API
- NOAA National Weather Service API (api.weather.gov) vs Xweather Weather API
- OpenWeather One Call API vs Xweather Weather API
- Pirate Weather vs Xweather Weather API
- Tomorrow.io Weather API vs Xweather Weather API
- Visual Crossing Weather API vs Xweather Weather API
- The Weather Company Data APIs vs Xweather Weather API
- WeatherAPI.com vs Xweather Weather API
- Weatherbit API vs Xweather Weather API
- AccuWeather Core Weather API + MCP vs Meteosource Weather MCP
- Google Weather API (Maps Platform) vs Meteosource Weather MCP
- Met Office Weather DataHub (Site Specific) vs Meteosource Weather MCP
- meteoblue Weather API vs Meteosource Weather MCP
- Meteomatics Weather API vs Meteosource Weather MCP
- Meteosource Weather MCP vs NOAA National Weather Service API (api.weather.gov)
- Meteosource Weather MCP vs OpenWeather One Call API
- Meteosource Weather MCP vs Pirate Weather
- Meteosource Weather MCP vs Stormglass API
- Meteosource Weather MCP vs Tomorrow.io Weather API
- Meteosource Weather MCP vs Visual Crossing Weather API
- Meteosource Weather MCP vs The Weather Company Data APIs
- Meteosource Weather MCP vs WeatherAPI.com
- Meteosource Weather MCP vs Weatherbit API
- Stormglass API vs Xweather Weather API
- Meteosource Weather MCP vs Open-Meteo
- Open-Meteo vs Xweather Weather API
Machine-readable
- This page as Markdown
/compare/meteosource-mcp-vs-xweather.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/meteosource-mcp.json·/api/v1/tools/xweather.json - From a terminal
anchor compare meteosource-mcp xweather(the CLI) - Over MCP
compare_tools {"a": "meteosource-mcp", "b": "xweather"}at/mcp, no key