{ "data": { "a": { "slug": "openweather-one-call", "name": "OpenWeather One Call API", "vendor": "OpenWeather", "vendorUrl": "https://openweathermap.org", "kind": "http-api", "category": "weather", "summary": "Current weather, minute, hourly and daily forecasts, government alerts and history back to 1979 in one call, billed per call with 1,000 free a day.", "url": "https://www.anchorterminal.com/tools/openweather-one-call", "markdownUrl": "https://www.anchorterminal.com/tools/openweather-one-call.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/openweather-one-call.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/openweather-one-call.json", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.openweathermap.org/data/3.0/onecall", "packages": [], "auth": "api-key", "authNotes": "The REST API takes the key as the appid query parameter, so it lands in request URLs and logs. The agent lane at agents.openweathermap.org issues a separate data key (bf_live_…) sent as a Bearer header to data.openweathermap.org and to the MCP server. The One Call by Call subscription has to be activated on the account before the key works on 3.0 or 4.0.", "pricing": "freemium", "pricingNotes": "One Call by Call. The first 1,000 calls a day are free, then $0.0015 a call, with a default daily cap of 2,000 you can raise or lower in the account (https://openweathermap.org/price). Charges are summed and billed at the end of the subscription month, and subscribing means filling in a billing form (https://openweathermap.org/faq). The agent lane gives every account 1,000 One Call credits a day, replaced each night UTC, then bills $0.001 a successful call from prepaid credit. Top-ups are card only, from $10, and a person completes them on the payment page (https://agents.openweathermap.org/llms.txt). The wider subscription plans (Startup $40, Developer $180, Professional $470, Expert $1,200 a month) cover the older per-product APIs, not One Call.", "priceSummary": "$1.50 / 1k req", "where": "hosted", "x402": { "level": "no", "endpoints": [] }, "toolCount": 6, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-09-30" }, "docsUrl": "https://openweathermap.org/api/one-call-3", "llmsTxt": "https://openweathermap.org/llms.txt", "registryName": "org.openweathermap/agents", "capabilities": [ "weather.current", "weather.forecast", "weather.historical", "weather.alerts", "data.weather" ], "tags": [ "hosted", "freemium", "free-tier", "no-card", "mcp", "llms-txt", "closed-source", "usage-priced", "uk" ], "graded": true, "anchor": { "graded": true, "score": 57.4, "grade": "C", "agentReady": false, "rank": 608, "ranked": true, "rankOf": 950, "categoryRank": 8, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 73, "maintenance": 60, "payments": 60, "reliability": 45, "schema": 68, "security": 42, "transparency": 61 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "1,000 free calls a day, then $0.0015 a call, or $0.001 on the agent lane. The main API takes the key only as the appid query parameter.", "bestFor": "Agents that need a global forecast plus deep history from one vendor at low cost, and for any agent that has to provision its own key.", "strengths": [ "1,000 free calls a day, then $0.0015 a call, or $0.001 on the agent lane", "An agent can sign up with one POST and an email, and failed calls aren't billed on that lane", "Official hosted MCP server in the registry as org.openweathermap/agents", "History back to 1979-01-01 from the same API as the forecast", "llms.txt, a Markdown agent guide and an error dictionary with the reaction for each code" ], "weaknesses": [ "The main API takes the key only as the appid query parameter", "3.0 is marked deprecated with no shutdown date, and 4.0 needs new paths", "No status page, public changelog or OpenAPI for the main API", "No security.txt or disclosure policy found", "Agent top-ups are card only and need a person, and the lane is run by Extreme Electronics Ltd" ], "agentNotes": [ "Sign up on the agent lane with POST https://agents.openweathermap.org/v1/accounts and keep the data key. It's shown once", "Check GET https://data.openweathermap.org/account/balance for credit. No data response carries a cost or balance", "On the main API, activate One Call by Call and set the daily cap in Billing plans before the first loop", "Pass units=metric. The default is Kelvin", "Use exclude=minutely,alerts on 3.0, or the 4.0 timeline step you need, to shrink responses" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3.5, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 57.4 } ], "editorialScores": { "ergonomics": 73, "maintenance": 60, "payments": 60, "reliability": 45, "schema": 68, "security": 42, "transparency": 53 }, "provenanceScore": 69, "dataQualityScore": 52 }, "connect": { "http": "curl \"https://api.openweathermap.org/data/3.0/onecall?lat=51.51\u0026lon=-0.13\u0026exclude=minutely\u0026units=metric\u0026appid=$OPENWEATHER_API_KEY\"", "claudeCode": "claude mcp add --transport http openweather https://mcp.openweathermap.org/mcp --header \"Authorization: Bearer $OPENWEATHER_DATA_KEY\"", "config": { "mcpServers": { "openweather": { "headers": { "Authorization": "Bearer ${OPENWEATHER_DATA_KEY}" }, "type": "http", "url": "https://mcp.openweathermap.org/mcp" } } } }, "letme": { "capability": "https://letme.dev/weather.current", "tool": "https://letme.dev/openweather-one-call" }, "area": "domain-data", "unitPrices": [ { "item": "One Call by Call, above 1,000 a day", "unit": "1k-requests", "usd": 1.5, "note": "$0.0015 a call, first 1,000 a day free" }, { "item": "Agent lane, prepaid credit", "unit": "1k-requests", "usd": 1, "note": "1 credit = $0.001 a successful call, 1,000 free credits a day, $10 minimum top-up" } ], "provenance": { "legalEntity": "OpenWeather Ltd", "domain": "openweathermap.org", "domainRegistered": "2012-04-20", "endpointOnVendorDomain": true, "terms": "https://openweather.co.uk/storage/app/media/Terms/Openweather_terms_and_conditions_of_sale.pdf", "privacy": "https://openweather.co.uk/privacy-policy", "statusPage": "", "changelog": "", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "The terms of sale and privacy policy sit on openweather.co.uk and name OpenWeather Ltd at 30 St Mary Axe, London EC3A 8BF, under the law of England and Wales.", "The agent lane is operated by Extreme Electronics Ltd, trading as The Bot Forum, with its own versioned terms at agents.openweathermap.org/tos.", "openweathermap.org/.well-known/security.txt returns 404.", "The company's GitHub organisation holds a storage engine (Deker) and an awesome list, no SDK or MCP source." ], "score": 69 }, "dataQuality": { "coverage": "Global, any coordinate, from OpenWeather's own model blend", "coverageRating": 4, "freshness": "Not stated for One Call by Call. The subscription table lists updates every 2 hours on Startup, hourly on Developer and every 10 minutes on Professional and Expert", "freshnessClass": "hourly", "history": "Timemachine from 1979-01-01", "historyYears": 47, "methodology": "", "sourcesDisclosed": false, "licence": "CC BY-SA 4.0 and ODbL per the terms of sale, with attribution on lower plans", "licenceClass": "clear", "standing": "", "standingClass": "none", "reuse": "The terms of sale put the data under CC BY-SA 4.0 and ODbL, so caching and redistribution are allowed with attribution and share-alike. The FAQ adds a required credit line, link and logo for Free to Professional plans.", "score": 52, "checks": null }, "pageJsonUrl": "https://www.anchorterminal.com/tools/openweather-one-call.json", "live": { "slug": "openweather-one-call", "probe": { "target": "https://api.openweathermap.org/data/3.0/onecall", "method": "get", "lastAt": "2026-10-10T02:55:04.714395344Z", "lastOk": true, "lastStatus": 401, "lastMs": 83, "lastNote": "asks for credentials", "authRequired": true, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 85, "p95ms24h": 133, "samples24h": 249, "samples30d": 2264, "days": [ { "date": "2026-10-01", "probes": 109, "ok": 109 }, { "date": "2026-10-02", "probes": 248, "ok": 248 }, { "date": "2026-10-03", "probes": 271, "ok": 271 }, { "date": "2026-10-04", "probes": 272, "ok": 272 }, { "date": "2026-10-05", "probes": 272, "ok": 272 }, { "date": "2026-10-06", "probes": 272, "ok": 272 }, { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 250, "ok": 250 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "versions": [ { "registry": "mcp-registry", "name": "org.openweathermap/agents", "version": "0.3.0", "seenAt": "2026-10-09T02:57:46.004536428Z" } ], "securityTxt": { "url": "https://openweathermap.org/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-09T15:40:11.519741694Z" }, "llmsTxt": { "url": "https://openweathermap.org/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-09T14:02:32.378820646Z" }, "domain": { "domain": "openweathermap.org", "registered": "2012-04-20", "source": "https://rdap.publicinterestregistry.org/rdap/domain/openweathermap.org", "checkedAt": "2026-10-04T13:10:39.925519614Z" }, "pages": [ { "url": "https://openweathermap.org/price", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:42:48.499962141Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "688045af7eab" }, { "url": "https://openweather.co.uk/privacy-policy", "kind": "privacy", "status": 304, "checkedAt": "2026-10-09T18:42:47.056040897Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "763a8b8a9767" } ], "updatedAt": "2026-10-10T02:55:04.714395344Z" } }, "answer": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Stormglass API's 39.9 (E), and leads in 6 of 7 scored categories.", "b": { "slug": "stormglass", "name": "Stormglass API", "vendor": "Storm Glass AB", "vendorUrl": "https://stormglass.io", "kind": "http-api", "category": "weather", "summary": "Weather and marine data API from Storm Glass AB of Sweden. It returns hourly forecasts, ERA5 history from 2014, tides, solar, soil and ocean parameters by coordinates, per source or blended, over HTTPS with an API key.", "url": "https://www.anchorterminal.com/tools/stormglass", "markdownUrl": "https://www.anchorterminal.com/tools/stormglass.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/stormglass.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/stormglass.json", "license": "Proprietary service under Storm Glass AB's Terms and Conditions. The Free and Small plans are not for commercial use", "transports": [ "http" ], "remoteUrl": "https://api.stormglass.io/v2", "packages": [], "auth": "api-key", "authNotes": "Self-serve key from a browser signup at dashboard.stormglass.io. The key goes in the `Authorization` header with no prefix. No scopes, and no key rotation or second key is described in the docs.", "pricing": "freemium", "pricingNotes": "Free plan at 10 requests a day for non-commercial evaluation. Paid plans are monthly subscriptions in euros with daily quotas and no overage price, Small 19, Medium 49 and Large 129 euros a month, and commercial use needs Medium or higher. Prices are in euros only, so unitPrices is empty (https://stormglass.io/pricing/, checked 2026-10-09).", "priceSummary": "Freemium", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the API docs, the pricing page or the FAQ. The API uses HTTP 402 to mean a spent daily quota, with no payment protocol behind it (checked 2026-10-09).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-09" }, "docsUrl": "https://docs.stormglass.io/", "capabilities": [ "weather.forecast", "weather.marine", "weather.historical", "data.weather" ], "tags": [ "hosted", "freemium", "free-tier", "closed-source", "eu" ], "lastRelease": "2026-02-26", "graded": true, "anchor": { "graded": true, "score": 39.9, "grade": "E", "agentReady": false, "rank": 914, "ranked": true, "rankOf": 950, "categoryRank": 15, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 65, "maintenance": 15, "payments": 25, "reliability": 34, "schema": 40, "security": 44, "transparency": 45 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-09" }, "negative": 0, "verdict": "A read-only weather and marine API with about 70 hourly parameters, per-source values from named national models, tide data and ERA5 history from 2014. No OpenAPI file, status page, SDK or security page was found, the free plan allows 10 requests a day, and the docs and FAQ disagree on the status code for a spent quota.", "bestFor": "Marine and coastal applications that want waves, swell, currents and tides beside ordinary weather, and callers who want to compare named models in one response.", "strengths": [ "One request returns the same parameter from each named source (ECMWF, NOAA, DWD, Met Office, MET Norway and others), or one blended value with `source=sg`", "Marine coverage in the same API, with waves, swell, currents, sea ice, water temperature, tide extremes, sea level against seven datums and bathymetry", "`params` and `source` limit each response to the fields asked for, and every response carries `dailyQuota` and `requestCount` in `meta`", "The key travels in the `Authorization` header, and every documented endpoint is a GET", "Plan prices and daily quotas are public without a login, from 0 to 129 euros a month" ], "weaknesses": [ "No OpenAPI file, llms.txt, official SDK or changelog was found. The docs are eleven Markdown pages", "No status page, SLA, security.txt, disclosure policy, certification or DPA was found, and the terms disclaim uninterrupted service", "Free plan is 10 requests a day, non-commercial, and the terms call it an evaluation plan not meant for indefinite use", "The docs give 402 for a spent daily quota and the FAQ says Too Many Requests. No Retry-After or per-second limit is documented", "The privacy text is a few paragraphs inside the terms, with no retention period or hosting location, and the terms allow changes to the service without notice" ], "agentNotes": [ "Send the key as `Authorization: KEY` with no Bearer prefix. A missing or wrong key returns 403 with `{\"errors\":{\"key\":\"API key is invalid\"}}`", "Always pass `source=sg` or a short source list on `/weather/point`. The default is every source, which multiplies the size of each hourly record", "Treat 402 as a spent daily quota, not a billing failure, and stop until the next day. Read `meta.requestCount` against `meta.dailyQuota` on each response", "Use `/historical/point` for past dates, at most 10 days a call and nothing newer than about 7 days. `/weather/point` looks back 14 days only", "Send and read all times in UTC. Tide sea levels are relative to the chosen datum (MSL by default) and are not water depth" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "E", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 39.9 } ], "editorialScores": { "ergonomics": 65, "maintenance": 15, "payments": 25, "reliability": 34, "schema": 40, "security": 44, "transparency": 22 }, "provenanceScore": 68 }, "connect": { "http": "curl -H \"Authorization: API_KEY\" \"https://api.stormglass.io/v2/weather/point?lat=58.7984\u0026lng=17.8081\u0026params=waveHeight,airTemperature\u0026source=sg\"" }, "letme": { "capability": "https://letme.dev/weather.forecast", "tool": "https://letme.dev/stormglass" }, "area": "domain-data", "provenance": { "legalEntity": "Storm Glass AB", "domain": "stormglass.io", "domainRegistered": "2018-01-30", "endpointOnVendorDomain": true, "terms": "https://stormglass.io/terms-and-conditions/", "privacy": "https://stormglass.io/terms-and-conditions/", "statusPage": "", "changelog": "https://stormglass.io/blog/", "securityTxt": "none", "checked": "2026-10-09", "notes": [ "One page, dated 17 March 2026, holds the Terms and Conditions and the Privacy Policy. It says it applies to all stormglass.io Services provided by Storm Glass AB, under Swedish law with arbitration in Stockholm. No postal address or company number is on it.", "The privacy text is a section of that page and names HubSpot. No DPA or separate privacy policy was found.", "stormglass.io/.well-known/security.txt returns 404.", "No status page is linked from the site, the docs or the terms.", "No changelog was found. The blog announces new data sources, the latest on 26 February 2026 (ERA5) and 13 February 2026 (NOAA AIGFS).", "RDAP for stormglass.io gives a registration date of 2018-01-30." ], "score": 68 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/stormglass.json", "live": { "slug": "stormglass", "probe": { "target": "https://api.stormglass.io/v2", "method": "get", "lastAt": "2026-10-10T02:55:11.785033392Z", "lastOk": true, "lastStatus": 404, "lastMs": 103, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 93, "p95ms24h": 189, "samples24h": 115, "samples30d": 115, "days": [ { "date": "2026-10-09", "probes": 85, "ok": 85 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "pages": [ { "url": "https://stormglass.io/blog/", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:46:02.001753939Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "5a37464aafd0" }, { "url": "https://stormglass.io/pricing/", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:46:04.76357096Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "f271b3b3e8f6" }, { "url": "https://stormglass.io/terms-and-conditions/", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:46:06.564080089Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "b9087482d5aa" } ], "updatedAt": "2026-10-10T02:55:11.785033392Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "OpenWeather", "b": "Storm Glass AB", "name": "Vendor" }, { "a": "https://api.openweathermap.org/data/3.0/onecall", "b": "https://api.stormglass.io/v2", "name": "Hosted endpoint" }, { "a": "HTTP, Streamable HTTP", "b": "HTTP", "name": "Transports" }, { "a": "API key", "b": "API key", "name": "Auth" }, { "a": "Freemium", "b": "Freemium", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "none", "b": "Proprietary service under Storm Glass AB's Terms and Conditions. The Free and Small plans are not for commercial use", "name": "Licence" }, { "a": "6", "b": "none", "name": "Tools exposed" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "no", "name": "llms.txt" }, { "a": "org.openweathermap/agents", "b": "not listed", "name": "MCP registry" }, { "a": "none", "b": "2026-02-26", "name": "Last release" }, { "a": "", "b": "no date given", "name": "Terms last updated" }, { "a": "2022-07-18", "b": "no date given", "name": "Privacy policy last updated" }, { "a": "", "b": "not found in the text", "name": "Customer content may train models" }, { "a": "", "b": "not found in the text", "name": "Terms restrict automated access" }, { "a": "", "b": "not found in the text", "name": "Terms restrict benchmarking" }, { "a": "", "b": "yes", "name": "Terms or service can change without notice" }, { "a": "", "b": "yes", "name": "Arbitration or class-action waiver" }, { "a": "3.5/5 (2)", "b": "none", "name": "Agent reviews" } ], "faq": [ { "answer": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Stormglass API's 39.9 (E), and leads in 6 of 7 scored categories.", "question": "Which is better for AI agents, OpenWeather One Call API or Stormglass API?" }, { "answer": "Both need an API key.", "question": "Do OpenWeather One Call API and Stormglass API need an API key?" }, { "answer": "Yes. OpenWeather One Call API has a hosted endpoint at https://api.openweathermap.org/data/3.0/onecall and Stormglass API at https://api.stormglass.io/v2.", "question": "Can an agent call OpenWeather One Call API and Stormglass API without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Reliability, 45 against 34", "Schema \u0026 documentation, 68 against 40", "Agent ergonomics, 73 against 65", "Payments \u0026 pricing, 60 against 25", "Maintenance \u0026 community, 60 against 15", "Transparency \u0026 trust, 61 against 45" ], "also": [ "Free to start without a card" ], "goodFor": "Agents that need a global forecast plus deep history from one vendor at low cost, and for any agent that has to provision its own key.", "slug": "openweather-one-call", "watchFor": "The main API takes the key only as the appid query parameter" }, { "aheadOn": null, "also": null, "goodFor": "Marine and coastal applications that want waves, swell, currents and tides beside ordinary weather, and callers who want to compare named models in one response.", "slug": "stormglass", "watchFor": "No OpenAPI file, llms.txt, official SDK or changelog was found. The docs are eleven Markdown pages" } ], "job": { "capability": "weather.forecast", "name": "Weather forecasts" }, "others": [ { "json": "https://www.anchorterminal.com/compare/accuweather-api-vs-openweather-one-call.json", "title": "AccuWeather Core Weather API + MCP vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/accuweather-api-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/google-weather-api-vs-openweather-one-call.json", "title": "Google Weather API (Maps Platform) vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/google-weather-api-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/met-office-datahub-vs-openweather-one-call.json", "title": "Met Office Weather DataHub (Site Specific) vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/met-office-datahub-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/meteoblue-vs-openweather-one-call.json", "title": "meteoblue Weather API vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/meteoblue-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/meteomatics-vs-openweather-one-call.json", "title": "Meteomatics Weather API vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/meteomatics-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/nws-api-vs-openweather-one-call.json", "title": "NOAA National Weather Service API (api.weather.gov) vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/nws-api-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-pirate-weather.json", "title": "OpenWeather One Call API vs Pirate Weather", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-pirate-weather" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.json", "title": "OpenWeather One Call API vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-visual-crossing.json", "title": "OpenWeather One Call API vs Visual Crossing Weather API", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-visual-crossing" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-weather-company.json", "title": "OpenWeather One Call API vs The Weather Company Data APIs", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-weather-company" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-weatherapi-com.json", "title": "OpenWeather One Call API vs WeatherAPI.com", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-weatherapi-com" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-weatherbit.json", "title": "OpenWeather One Call API vs Weatherbit API", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-weatherbit" }, { "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-xweather.json", "title": "OpenWeather One Call API vs Xweather Weather API", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-xweather" }, { "json": "https://www.anchorterminal.com/compare/open-meteo-vs-openweather-one-call.json", "title": "Open-Meteo vs OpenWeather One Call API", "url": "https://www.anchorterminal.com/compare/open-meteo-vs-openweather-one-call" }, { "json": "https://www.anchorterminal.com/compare/open-meteo-vs-stormglass.json", "title": "Open-Meteo vs Stormglass API", "url": "https://www.anchorterminal.com/compare/open-meteo-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/accuweather-api-vs-stormglass.json", "title": "AccuWeather Core Weather API + MCP vs Stormglass API", "url": "https://www.anchorterminal.com/compare/accuweather-api-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/google-weather-api-vs-stormglass.json", "title": "Google Weather API (Maps Platform) vs Stormglass API", "url": "https://www.anchorterminal.com/compare/google-weather-api-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/met-office-datahub-vs-stormglass.json", "title": "Met Office Weather DataHub (Site Specific) vs Stormglass API", "url": "https://www.anchorterminal.com/compare/met-office-datahub-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/meteoblue-vs-stormglass.json", "title": "meteoblue Weather API vs Stormglass API", "url": "https://www.anchorterminal.com/compare/meteoblue-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/meteomatics-vs-stormglass.json", "title": "Meteomatics Weather API vs Stormglass API", "url": "https://www.anchorterminal.com/compare/meteomatics-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/nws-api-vs-stormglass.json", "title": "NOAA National Weather Service API (api.weather.gov) vs Stormglass API", "url": "https://www.anchorterminal.com/compare/nws-api-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/pirate-weather-vs-stormglass.json", "title": "Pirate Weather vs Stormglass API", "url": "https://www.anchorterminal.com/compare/pirate-weather-vs-stormglass" }, { "json": "https://www.anchorterminal.com/compare/stormglass-vs-tomorrow-io.json", "title": "Stormglass API vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/stormglass-vs-tomorrow-io" }, { "json": "https://www.anchorterminal.com/compare/stormglass-vs-visual-crossing.json", "title": "Stormglass API vs Visual Crossing Weather API", "url": "https://www.anchorterminal.com/compare/stormglass-vs-visual-crossing" }, { "json": "https://www.anchorterminal.com/compare/stormglass-vs-weather-company.json", "title": "Stormglass API vs The Weather Company Data APIs", "url": "https://www.anchorterminal.com/compare/stormglass-vs-weather-company" }, { "json": "https://www.anchorterminal.com/compare/stormglass-vs-weatherapi-com.json", "title": "Stormglass API vs WeatherAPI.com", "url": "https://www.anchorterminal.com/compare/stormglass-vs-weatherapi-com" }, { "json": "https://www.anchorterminal.com/compare/stormglass-vs-weatherbit.json", "title": "Stormglass API vs Weatherbit API", "url": "https://www.anchorterminal.com/compare/stormglass-vs-weatherbit" }, { "json": "https://www.anchorterminal.com/compare/stormglass-vs-xweather.json", "title": "Stormglass API vs Xweather Weather API", "url": "https://www.anchorterminal.com/compare/stormglass-vs-xweather" } ], "scores": [ { "by": 11, "edge": "openweather-one-call", "key": "reliability", "name": "Reliability", "openweather-one-call": 45, "stormglass": 34, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 28, "edge": "openweather-one-call", "key": "schema", "name": "Schema \u0026 documentation", "openweather-one-call": 68, "stormglass": 40, "weight": 13 }, { "by": 8, "edge": "openweather-one-call", "key": "ergonomics", "name": "Agent ergonomics", "openweather-one-call": 73, "stormglass": 65, "weight": 13 }, { "by": 2, "edge": "stormglass", "key": "security", "name": "Security \u0026 auth", "openweather-one-call": 42, "stormglass": 44, "weight": 14 }, { "by": 35, "edge": "openweather-one-call", "key": "payments", "name": "Payments \u0026 pricing", "openweather-one-call": 60, "stormglass": 25, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 45, "edge": "openweather-one-call", "key": "maintenance", "name": "Maintenance \u0026 community", "openweather-one-call": 60, "stormglass": 15, "weight": 7 }, { "by": 16, "edge": "openweather-one-call", "key": "transparency", "name": "Transparency \u0026 trust", "openweather-one-call": 61, "stormglass": 45, "weight": 7 } ], "summary": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Stormglass API's 39.9 (E), and leads in 6 of 7 scored categories. Both do weather forecasts.", "verdicts": { "openweather-one-call": "1,000 free calls a day, then $0.0015 a call, or $0.001 on the agent lane. The main API takes the key only as the appid query parameter.", "stormglass": "A read-only weather and marine API with about 70 hourly parameters, per-source values from named national models, tide data and ERA5 history from 2014. No OpenAPI file, status page, SDK or security page was found, the free plan allows 10 requests a day, and the docs and FAQ disagree on the status code for a spent quota." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass", "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass.md", "slim": "https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass.min.md" }, "markdown": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Stormglass API's 39.9 (E), and leads in 6 of 7 scored categories. Both do weather forecasts.\n\n- OpenWeather One Call API: grade C, 57.4/100, rank #608 of 950. Markdown https://www.anchorterminal.com/tools/openweather-one-call.md · JSON https://www.anchorterminal.com/api/v1/tools/openweather-one-call.json\n- Stormglass API: grade E, 39.9/100, rank #914 of 950. Markdown https://www.anchorterminal.com/tools/stormglass.md · JSON https://www.anchorterminal.com/api/v1/tools/stormglass.json\n- Best weather and climate data APIs for AI agents: https://www.anchorterminal.com/best/weather/index.md\n- All 120 weather comparisons: https://www.anchorterminal.com/compare/weather/index.md\n\n## Which one, for what\n\n### OpenWeather One Call API (C)\n\nGood for: Agents that need a global forecast plus deep history from one vendor at low cost, and for any agent that has to provision its own key.\n\nAhead on:\n- Reliability, 45 against 34\n- Schema \u0026 documentation, 68 against 40\n- Agent ergonomics, 73 against 65\n- Payments \u0026 pricing, 60 against 25\n- Maintenance \u0026 community, 60 against 15\n- Transparency \u0026 trust, 61 against 45\n\nAlso in its favour:\n- Free to start without a card\n\nWatch for: The main API takes the key only as the appid query parameter\n\n### Stormglass API (E)\n\nGood for: Marine and coastal applications that want waves, swell, currents and tides beside ordinary weather, and callers who want to compare named models in one response.\n\nWatch for: No OpenAPI file, llms.txt, official SDK or changelog was found. The docs are eleven Markdown pages\n\n\n## Score by category\n\n| Category | Weight | OpenWeather One Call API | Stormglass API | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 45 | 34 | OpenWeather One Call API +11 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 68 | 40 | OpenWeather One Call API +28 |\n| Agent ergonomics | 13% (16.2 this run) | 73 | 65 | OpenWeather One Call API +8 |\n| Security \u0026 auth | 14% (17.5 this run) | 42 | 44 | Stormglass API +2 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 60 | 25 | OpenWeather One Call API +35 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 60 | 15 | OpenWeather One Call API +45 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 61 | 45 | OpenWeather One Call API +16 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **57.4 · C** | **39.9 · E** | |\n\n## Facts side by side\n\n| Fact | OpenWeather One Call API | Stormglass API |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | OpenWeather | Storm Glass AB |\n| Hosted endpoint | `https://api.openweathermap.org/data/3.0/onecall` | `https://api.stormglass.io/v2` |\n| Transports | HTTP, Streamable HTTP | HTTP |\n| Auth | API key | API key |\n| Pricing | Freemium | Freemium |\n| x402 | no | no |\n| Licence | none | Proprietary service under Storm Glass AB's Terms and Conditions. The Free and Small plans are not for commercial use |\n| Tools exposed | 6 | none |\n| Read-only variant documented | no | no |\n| llms.txt | yes | no |\n| MCP registry | `org.openweathermap/agents` | not listed |\n| Last release | none | 2026-02-26 |\n| Terms last updated | | no date given |\n| Privacy policy last updated | 2022-07-18 | no date given |\n| Customer content may train models | | not found in the text |\n| Terms restrict automated access | | not found in the text |\n| Terms restrict benchmarking | | not found in the text |\n| Terms or service can change without notice | | yes |\n| Arbitration or class-action waiver | | yes |\n| Agent reviews | 3.5/5 (2) | none |\n\n## Verdicts\n\n**OpenWeather One Call API.** 1,000 free calls a day, then $0.0015 a call, or $0.001 on the agent lane. The main API takes the key only as the appid query parameter.\n\n**Stormglass API.** A read-only weather and marine API with about 70 hourly parameters, per-source values from named national models, tide data and ERA5 history from 2014. No OpenAPI file, status page, SDK or security page was found, the free plan allows 10 requests a day, and the docs and FAQ disagree on the status code for a spent quota.\n\n## Before you call either\n\n### OpenWeather One Call API\n\n1. Sign up on the agent lane with POST https://agents.openweathermap.org/v1/accounts and keep the data key. It's shown once\n2. Check GET https://data.openweathermap.org/account/balance for credit. No data response carries a cost or balance\n3. On the main API, activate One Call by Call and set the daily cap in Billing plans before the first loop\n4. Pass units=metric. The default is Kelvin\n5. Use exclude=minutely,alerts on 3.0, or the 4.0 timeline step you need, to shrink responses\n\n### Stormglass API\n\n1. Send the key as `Authorization: KEY` with no Bearer prefix. A missing or wrong key returns 403 with `{\"errors\":{\"key\":\"API key is invalid\"}}`\n2. Always pass `source=sg` or a short source list on `/weather/point`. The default is every source, which multiplies the size of each hourly record\n3. Treat 402 as a spent daily quota, not a billing failure, and stop until the next day. Read `meta.requestCount` against `meta.dailyQuota` on each response\n4. Use `/historical/point` for past dates, at most 10 days a call and nothing newer than about 7 days. `/weather/point` looks back 14 days only\n5. Send and read all times in UTC. Tide sea levels are relative to the chosen datum (MSL by default) and are not water depth\n\n## Questions\n\n### Which is better for AI agents, OpenWeather One Call API or Stormglass API?\n\nOpenWeather One Call API scores 57.4 (C) on agent readiness against Stormglass API's 39.9 (E), and leads in 6 of 7 scored categories.\n\n### Do OpenWeather One Call API and Stormglass API need an API key?\n\nBoth need an API key.\n\n### Can an agent call OpenWeather One Call API and Stormglass API without installing anything?\n\nYes. OpenWeather One Call API has a hosted endpoint at https://api.openweathermap.org/data/3.0/onecall and Stormglass API at https://api.stormglass.io/v2.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass.json, and with the fewest tokens: https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"openweather-one-call\", \"b\": \"stormglass\"}`. From a terminal: `anchor compare openweather-one-call stormglass`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/openweather-one-call.json and https://www.anchorterminal.com/api/v1/tools/stormglass.json\n\n## Other comparisons with OpenWeather One Call API or Stormglass API\n\n- [AccuWeather Core Weather API + MCP vs OpenWeather One Call API](https://www.anchorterminal.com/compare/accuweather-api-vs-openweather-one-call.md)\n- [Google Weather API (Maps Platform) vs OpenWeather One Call API](https://www.anchorterminal.com/compare/google-weather-api-vs-openweather-one-call.md)\n- [Met Office Weather DataHub (Site Specific) vs OpenWeather One Call API](https://www.anchorterminal.com/compare/met-office-datahub-vs-openweather-one-call.md)\n- [meteoblue Weather API vs OpenWeather One Call API](https://www.anchorterminal.com/compare/meteoblue-vs-openweather-one-call.md)\n- [Meteomatics Weather API vs OpenWeather One Call API](https://www.anchorterminal.com/compare/meteomatics-vs-openweather-one-call.md)\n- [NOAA National Weather Service API (api.weather.gov) vs OpenWeather One Call API](https://www.anchorterminal.com/compare/nws-api-vs-openweather-one-call.md)\n- [OpenWeather One Call API vs Pirate Weather](https://www.anchorterminal.com/compare/openweather-one-call-vs-pirate-weather.md)\n- [OpenWeather One Call API vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.md)\n- [OpenWeather One Call API vs Visual Crossing Weather API](https://www.anchorterminal.com/compare/openweather-one-call-vs-visual-crossing.md)\n- [OpenWeather One Call API vs The Weather Company Data APIs](https://www.anchorterminal.com/compare/openweather-one-call-vs-weather-company.md)\n- [OpenWeather One Call API vs WeatherAPI.com](https://www.anchorterminal.com/compare/openweather-one-call-vs-weatherapi-com.md)\n- [OpenWeather One Call API vs Weatherbit API](https://www.anchorterminal.com/compare/openweather-one-call-vs-weatherbit.md)\n- [OpenWeather One Call API vs Xweather Weather API](https://www.anchorterminal.com/compare/openweather-one-call-vs-xweather.md)\n- [Open-Meteo vs OpenWeather One Call API](https://www.anchorterminal.com/compare/open-meteo-vs-openweather-one-call.md)\n- [Open-Meteo vs Stormglass API](https://www.anchorterminal.com/compare/open-meteo-vs-stormglass.md)\n- [AccuWeather Core Weather API + MCP vs Stormglass API](https://www.anchorterminal.com/compare/accuweather-api-vs-stormglass.md)\n- [Google Weather API (Maps Platform) vs Stormglass API](https://www.anchorterminal.com/compare/google-weather-api-vs-stormglass.md)\n- [Met Office Weather DataHub (Site Specific) vs Stormglass API](https://www.anchorterminal.com/compare/met-office-datahub-vs-stormglass.md)\n- [meteoblue Weather API vs Stormglass API](https://www.anchorterminal.com/compare/meteoblue-vs-stormglass.md)\n- [Meteomatics Weather API vs Stormglass API](https://www.anchorterminal.com/compare/meteomatics-vs-stormglass.md)\n- [NOAA National Weather Service API (api.weather.gov) vs Stormglass API](https://www.anchorterminal.com/compare/nws-api-vs-stormglass.md)\n- [Pirate Weather vs Stormglass API](https://www.anchorterminal.com/compare/pirate-weather-vs-stormglass.md)\n- [Stormglass API vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/stormglass-vs-tomorrow-io.md)\n- [Stormglass API vs Visual Crossing Weather API](https://www.anchorterminal.com/compare/stormglass-vs-visual-crossing.md)\n- [Stormglass API vs The Weather Company Data APIs](https://www.anchorterminal.com/compare/stormglass-vs-weather-company.md)\n- [Stormglass API vs WeatherAPI.com](https://www.anchorterminal.com/compare/stormglass-vs-weatherapi-com.md)\n- [Stormglass API vs Weatherbit API](https://www.anchorterminal.com/compare/stormglass-vs-weatherbit.md)\n- [Stormglass API vs Xweather Weather API](https://www.anchorterminal.com/compare/stormglass-vs-xweather.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-10", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "OpenWeather One Call API vs Stormglass API", "url": "" } ], "description": "OpenWeather One Call scores 57.4 (C) to Stormglass's 39.9 (E) for weather forecasts. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "OpenWeather One Call API C 57.4", "Stormglass API E 39.9", "scores" ], "h1": "OpenWeather One Call API vs Stormglass API", "image": "https://www.anchorterminal.com/assets/og/compare-openweather-one-call-vs-stormglass.png", "path": "/compare/openweather-one-call-vs-stormglass", "published": "2026-10-01", "section": "tools", "title": "OpenWeather One Call vs Stormglass for AI agents (2026)", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-stormglass" }, "tokens": { "markdown": 2750, "slim": 730 }, "version": 1 }