{ "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": 474, "ranked": true, "rankOf": 722, "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": "2026-10-08T19:52:58.143029906Z", "lastOk": true, "lastStatus": 401, "lastMs": 87, "lastNote": "asks for credentials", "authRequired": true, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 87, "p95ms24h": 132, "samples24h": 272, "samples30d": 1941, "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": 225, "ok": 225 } ] }, "versions": [ { "registry": "mcp-registry", "name": "org.openweathermap/agents", "version": "0.3.0", "seenAt": "2026-10-08T02:42:52.272076636Z" } ], "securityTxt": { "url": "https://openweathermap.org/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-08T15:38:35.212356314Z" }, "llmsTxt": { "url": "https://openweathermap.org/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-08T14:00:43.800574256Z" }, "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": "2026-10-08T18:22:41.570194601Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "688045af7eab" }, { "url": "https://openweather.co.uk/privacy-policy", "kind": "privacy", "status": 304, "checkedAt": "2026-10-08T18:22:39.654222195Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "763a8b8a9767" } ], "updatedAt": "2026-10-08T19:52:58.143029906Z" } }, "answer": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Tomorrow.io Weather API's 51.4 (D), and leads in 3 of 7 scored categories. Tomorrow.io Weather API leads on reliability and schema \u0026 documentation.", "b": { "slug": "tomorrow-io", "name": "Tomorrow.io Weather API", "vendor": "The Tomorrow Companies Inc.", "vendorUrl": "https://www.tomorrow.io", "kind": "http-api", "category": "weather", "summary": "Tomorrow.io's Weather API returns current conditions, forecasts, recent and archived history, map tiles, route weather and alert webhooks for a coordinate, place name or GeoJSON shape. It is a REST API with a hosted MCP server.", "url": "https://www.anchorterminal.com/tools/tomorrow-io", "markdownUrl": "https://www.anchorterminal.com/tools/tomorrow-io.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/tomorrow-io.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/tomorrow-io.json", "license": "Proprietary service under Tomorrow.io's subscription terms", "transports": [ "http" ], "remoteUrl": "https://api.tomorrow.io/v4", "packages": [], "auth": "mixed", "authNotes": "A person signs up in a browser and copies the key from the dashboard. The key goes in an `apikey` header or query parameter on REST calls and in `X-Api-Key` for the MCP server. The docs say keys carry full privileges, and more keys are created by an account manager. The MCP endpoint also advertises OAuth with dynamic client registration, PKCE and one scope, `mcp:read`.", "pricing": "freemium", "pricingNotes": "Free plan with no published price for anything above it. Free covers core data layers, a 5-day forecast, 24 hours of history, one monitored location and one alert, and the terms bar commercial use on self-generated accounts. Enterprise is by quote and adds the 14-day forecast, premium layers, routes, maps and the historical archive, which is metered in tokens with no public token price (https://www.tomorrow.io/weather-api/, checked 2026-10-08).", "priceSummary": "Freemium", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the docs, the OpenAPI file or the plan table (checked 2026-10-08).", "endpoints": [] }, "toolCount": 11, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-08" }, "docsUrl": "https://docs.tomorrow.io/reference/welcome", "llmsTxt": "https://docs.tomorrow.io/llms.txt", "openapi": "https://docs.tomorrow.io/openapi/tomorrowio-api.json", "capabilities": [ "weather.current", "weather.forecast", "weather.historical", "weather.alerts", "weather.marine", "data.weather" ], "tags": [ "hosted", "freemium", "free-tier", "closed-source", "openapi", "llms-txt", "mcp", "webhooks", "status-page", "sales-led", "us" ], "lastRelease": "2026-07-14", "graded": true, "anchor": { "graded": true, "score": 51.4, "grade": "D", "agentReady": false, "rank": 578, "ranked": true, "rankOf": 722, "categoryRank": 10, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 73, "maintenance": 27, "payments": 20, "reliability": 55, "schema": 75, "security": 34, "transparency": 63 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-08" }, "negative": 0, "verdict": "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.", "bestFor": "Teams that need minute-level and route or polygon forecasts, alert webhooks and a hosted MCP server, and will buy through sales.", "strengths": [ "Public OpenAPI 3.1.0 file (version 4.0.1, 31 paths, 39 operations), plus llms.txt and a Markdown copy of every docs page", "Hosted MCP server at api.tomorrow.io/v4/tomorrow-weather/mcp with 11 documented tools, added in April 2026", "The `fields`, `timesteps`, `startTime` and `endTime` parameters size a Timelines response to what the task needs", "Six-digit error codes that the docs say stay fixed, and soft warnings returned beside partial data", "Alert webhooks signed with HMAC-SHA256 in an `X-Signature` header, retried up to two times" ], "weaknesses": [ "No public price for paid use. The plan table lists Free and Enterprise, the second by quote", "The subscription terms bar commercial use on self-generated accounts and forbid storing unaltered data without an order", "No numeric rate limits in the reviewed docs, and remaining-limit headers are documented for Enterprise accounts only", "Keys carry full privileges and may be sent as an `apikey` query parameter. More keys come through an account manager", "50 incidents on the status page between 15 July and 2 October 2026, 25 naming the Timeline or Historical API", "No official SDK, no security.txt, and no certification or disclosure policy found on the pages read" ], "agentNotes": [ "Send the key in the `apikey` header, not the query string, so it stays out of URLs and logs", "Request only the `fields` and `timesteps` needed on POST /timelines. Free plans cover 24 hours back and 5 days ahead at `1h` and `1d`", "Split archive requests. POST /historical takes at most 31 days per call and deducts tokens, 1 for a point and 10 for a polygon", "Treat 401 with code 401001 as a missing or bad key. The docs say 403, the live API answered 401 on 8 October 2026", "On 429 back off without a hint. `Retry-After` is documented only for 503", "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" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "D", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 51.4 } ], "editorialScores": { "ergonomics": 73, "maintenance": 27, "payments": 20, "reliability": 55, "schema": 75, "security": 34, "transparency": 42 }, "provenanceScore": 84 }, "connect": { "http": "curl --request GET --url 'https://api.tomorrow.io/v4/weather/realtime?location=42.3478,-71.0466' --header 'apikey: API_KEY'", "config": { "mcpServers": { "tomorrow-weather-mcp": { "headers": { "X-Api-Key": "${TOMORROW_API_KEY}" }, "type": "http", "url": "https://api.tomorrow.io/v4/tomorrow-weather/mcp" } } } }, "letme": { "capability": "https://letme.dev/weather.current", "tool": "https://letme.dev/tomorrow-io" }, "area": "domain-data", "provenance": { "legalEntity": "The Tomorrow Companies Inc.", "domain": "tomorrow.io", "domainRegistered": "2012-02-15", "endpointOnVendorDomain": true, "terms": "https://www.tomorrow.io/legal/terms-of-service/", "privacy": "https://www.tomorrow.io/legal/product-privacy-policy/", "statusPage": "https://status.tomorrow.io", "changelog": "https://docs.tomorrow.io/reference/release-notes", "securityTxt": "none", "checked": "2026-10-08", "notes": [ "The subscription terms (last updated 19 October 2023) name The Tomorrow Companies Inc., a Delaware corporation with its principal place of business in Boston, Massachusetts, and cover the API, the dashboard and the data portal.", "The product privacy policy (last updated 17 December 2024) covers the API and platform and names Tomorrow.io Inc. as operator. The website has a separate privacy policy and terms of use, which we did not use here.", "The API and the MCP server answer at api.tomorrow.io.", "www.tomorrow.io, tomorrow.io and api.tomorrow.io each return 404 for /.well-known/security.txt.", "RDAP gives a registration date of 2012-02-15 for tomorrow.io. The status page runs on Atlassian Statuspage." ], "score": 84 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/tomorrow-io.json", "live": { "slug": "tomorrow-io", "probe": { "target": "https://api.tomorrow.io/v4", "method": "get", "lastAt": "2026-10-08T19:53:04.294618549Z", "lastOk": true, "lastStatus": 404, "lastMs": 149, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 152, "p95ms24h": 185, "samples24h": 27, "samples30d": 27, "days": [ { "date": "2026-10-08", "probes": 27, "ok": 27 } ] }, "vendorStatus": { "page": "https://status.tomorrow.io", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-08T19:51:05.559323966Z" }, "pages": [ { "url": "https://docs.tomorrow.io/reference/release-notes", "kind": "changelog", "status": 200, "checkedAt": "2026-10-08T18:19:37.617241436Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "5c08804d147f" }, { "url": "https://www.tomorrow.io/legal/product-privacy-policy/", "kind": "privacy", "status": 0, "checkedAt": "2026-10-08T18:31:01.004304542Z", "changedAt": "0001-01-01T00:00:00Z", "blockedByRobots": true }, { "url": "https://www.tomorrow.io/legal/terms-of-service/", "kind": "terms", "status": 0, "checkedAt": "2026-10-08T18:31:01.446636319Z", "changedAt": "0001-01-01T00:00:00Z", "blockedByRobots": true } ], "updatedAt": "2026-10-08T19:53:04.294618549Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "OpenWeather", "b": "The Tomorrow Companies Inc.", "name": "Vendor" }, { "a": "https://api.openweathermap.org/data/3.0/onecall", "b": "https://api.tomorrow.io/v4", "name": "Hosted endpoint" }, { "a": "HTTP, Streamable HTTP", "b": "HTTP", "name": "Transports" }, { "a": "API key", "b": "OAuth or key", "name": "Auth" }, { "a": "Freemium", "b": "Freemium", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "none", "b": "Proprietary service under Tomorrow.io's subscription terms", "name": "Licence" }, { "a": "6", "b": "11", "name": "Tools exposed" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "org.openweathermap/agents", "b": "not listed", "name": "MCP registry" }, { "a": "none", "b": "2026-07-14", "name": "Last release" }, { "a": "", "b": "couldn't be read", "name": "Terms last updated" }, { "a": "2022-07-18", "b": "couldn't be read", "name": "Privacy policy last updated" }, { "a": "", "b": "couldn't be read", "name": "Customer content may train models" }, { "a": "", "b": "couldn't be read", "name": "Terms restrict automated access" }, { "a": "", "b": "couldn't be read", "name": "Terms restrict benchmarking" }, { "a": "", "b": "couldn't be read", "name": "Terms or service can change without notice" }, { "a": "", "b": "couldn't be read", "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 Tomorrow.io Weather API's 51.4 (D), and leads in 3 of 7 scored categories. Tomorrow.io Weather API leads on reliability and schema \u0026 documentation.", "question": "Which is better for AI agents, OpenWeather One Call API or Tomorrow.io Weather API?" }, { "answer": "OpenWeather One Call API needs an API key. Tomorrow.io Weather API takes an API key or an OAuth sign-in.", "question": "Do OpenWeather One Call API and Tomorrow.io Weather 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 Tomorrow.io Weather API at https://api.tomorrow.io/v4.", "question": "Can an agent call OpenWeather One Call API and Tomorrow.io Weather API without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Security \u0026 auth, 42 against 34", "Payments \u0026 pricing, 60 against 20", "Maintenance \u0026 community, 60 against 27" ], "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": [ "Reliability, 55 against 45", "Schema \u0026 documentation, 75 against 68" ], "also": null, "goodFor": "Teams that need minute-level and route or polygon forecasts, alert webhooks and a hosted MCP server, and will buy through sales.", "slug": "tomorrow-io", "watchFor": "No public price for paid use. The plan table lists Free and Enterprise, the second by quote" } ], "job": { "capability": "weather.current", "name": "Weather current" }, "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/accuweather-api-vs-tomorrow-io.json", "title": "AccuWeather Core Weather API + MCP vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/accuweather-api-vs-tomorrow-io" }, { "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/google-weather-api-vs-tomorrow-io.json", "title": "Google Weather API (Maps Platform) vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/google-weather-api-vs-tomorrow-io" }, { "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/met-office-datahub-vs-tomorrow-io.json", "title": "Met Office Weather DataHub (Site Specific) vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/met-office-datahub-vs-tomorrow-io" }, { "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/meteoblue-vs-tomorrow-io.json", "title": "meteoblue Weather API vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/meteoblue-vs-tomorrow-io" }, { "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/meteomatics-vs-tomorrow-io.json", "title": "Meteomatics Weather API vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/meteomatics-vs-tomorrow-io" }, { "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/nws-api-vs-tomorrow-io.json", "title": "NOAA National Weather Service API (api.weather.gov) vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/nws-api-vs-tomorrow-io" }, { "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-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/pirate-weather-vs-tomorrow-io.json", "title": "Pirate Weather vs Tomorrow.io Weather API", "url": "https://www.anchorterminal.com/compare/pirate-weather-vs-tomorrow-io" }, { "json": "https://www.anchorterminal.com/compare/tomorrow-io-vs-visual-crossing.json", "title": "Tomorrow.io Weather API vs Visual Crossing Weather API", "url": "https://www.anchorterminal.com/compare/tomorrow-io-vs-visual-crossing" }, { "json": "https://www.anchorterminal.com/compare/tomorrow-io-vs-weather-company.json", "title": "Tomorrow.io Weather API vs The Weather Company Data APIs", "url": "https://www.anchorterminal.com/compare/tomorrow-io-vs-weather-company" }, { "json": "https://www.anchorterminal.com/compare/tomorrow-io-vs-weatherapi-com.json", "title": "Tomorrow.io Weather API vs WeatherAPI.com", "url": "https://www.anchorterminal.com/compare/tomorrow-io-vs-weatherapi-com" }, { "json": "https://www.anchorterminal.com/compare/tomorrow-io-vs-weatherbit.json", "title": "Tomorrow.io Weather API vs Weatherbit API", "url": "https://www.anchorterminal.com/compare/tomorrow-io-vs-weatherbit" }, { "json": "https://www.anchorterminal.com/compare/tomorrow-io-vs-xweather.json", "title": "Tomorrow.io Weather API vs Xweather Weather API", "url": "https://www.anchorterminal.com/compare/tomorrow-io-vs-xweather" } ], "scores": [ { "by": 10, "edge": "tomorrow-io", "key": "reliability", "name": "Reliability", "openweather-one-call": 45, "tomorrow-io": 55, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 7, "edge": "tomorrow-io", "key": "schema", "name": "Schema \u0026 documentation", "openweather-one-call": 68, "tomorrow-io": 75, "weight": 13 }, { "by": 0, "edge": "", "key": "ergonomics", "name": "Agent ergonomics", "openweather-one-call": 73, "tomorrow-io": 73, "weight": 13 }, { "by": 8, "edge": "openweather-one-call", "key": "security", "name": "Security \u0026 auth", "openweather-one-call": 42, "tomorrow-io": 34, "weight": 14 }, { "by": 40, "edge": "openweather-one-call", "key": "payments", "name": "Payments \u0026 pricing", "openweather-one-call": 60, "tomorrow-io": 20, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 33, "edge": "openweather-one-call", "key": "maintenance", "name": "Maintenance \u0026 community", "openweather-one-call": 60, "tomorrow-io": 27, "weight": 7 }, { "by": 2, "edge": "tomorrow-io", "key": "transparency", "name": "Transparency \u0026 trust", "openweather-one-call": 61, "tomorrow-io": 63, "weight": 7 } ], "summary": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Tomorrow.io Weather API's 51.4 (D), and leads in 3 of 7 scored categories. Tomorrow.io Weather API leads on reliability and schema \u0026 documentation. Both do weather current.", "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.", "tomorrow-io": "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." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io", "json": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.md", "slim": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.min.md" }, "markdown": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Tomorrow.io Weather API's 51.4 (D), and leads in 3 of 7 scored categories. Tomorrow.io Weather API leads on reliability and schema \u0026 documentation. Both do weather current.\n\n- OpenWeather One Call API: grade C, 57.4/100, rank #474 of 722. Markdown https://www.anchorterminal.com/tools/openweather-one-call.md · JSON https://www.anchorterminal.com/api/v1/tools/openweather-one-call.json\n- Tomorrow.io Weather API: grade D, 51.4/100, rank #578 of 722. Markdown https://www.anchorterminal.com/tools/tomorrow-io.md · JSON https://www.anchorterminal.com/api/v1/tools/tomorrow-io.json\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- Security \u0026 auth, 42 against 34\n- Payments \u0026 pricing, 60 against 20\n- Maintenance \u0026 community, 60 against 27\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### Tomorrow.io Weather API (D)\n\nGood for: Teams that need minute-level and route or polygon forecasts, alert webhooks and a hosted MCP server, and will buy through sales.\n\nAhead on:\n- Reliability, 55 against 45\n- Schema \u0026 documentation, 75 against 68\n\nWatch for: No public price for paid use. The plan table lists Free and Enterprise, the second by quote\n\n\n## Score by category\n\n| Category | Weight | OpenWeather One Call API | Tomorrow.io Weather API | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 45 | 55 | Tomorrow.io Weather API +10 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 68 | 75 | Tomorrow.io Weather API +7 |\n| Agent ergonomics | 13% (16.2 this run) | 73 | 73 | even |\n| Security \u0026 auth | 14% (17.5 this run) | 42 | 34 | OpenWeather One Call API +8 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 60 | 20 | OpenWeather One Call API +40 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 60 | 27 | OpenWeather One Call API +33 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 61 | 63 | Tomorrow.io Weather API +2 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **57.4 · C** | **51.4 · D** | |\n\n## Facts side by side\n\n| Fact | OpenWeather One Call API | Tomorrow.io Weather API |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | OpenWeather | The Tomorrow Companies Inc. |\n| Hosted endpoint | `https://api.openweathermap.org/data/3.0/onecall` | `https://api.tomorrow.io/v4` |\n| Transports | HTTP, Streamable HTTP | HTTP |\n| Auth | API key | OAuth or key |\n| Pricing | Freemium | Freemium |\n| x402 | no | no |\n| Licence | none | Proprietary service under Tomorrow.io's subscription terms |\n| Tools exposed | 6 | 11 |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| MCP registry | `org.openweathermap/agents` | not listed |\n| Last release | none | 2026-07-14 |\n| Terms last updated | | couldn't be read |\n| Privacy policy last updated | 2022-07-18 | couldn't be read |\n| Customer content may train models | | couldn't be read |\n| Terms restrict automated access | | couldn't be read |\n| Terms restrict benchmarking | | couldn't be read |\n| Terms or service can change without notice | | couldn't be read |\n| Arbitration or class-action waiver | | couldn't be read |\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**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.\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### Tomorrow.io Weather API\n\n1. Send the key in the `apikey` header, not the query string, so it stays out of URLs and logs\n2. Request only the `fields` and `timesteps` needed on POST /timelines. Free plans cover 24 hours back and 5 days ahead at `1h` and `1d`\n3. Split archive requests. POST /historical takes at most 31 days per call and deducts tokens, 1 for a point and 10 for a polygon\n4. Treat 401 with code 401001 as a missing or bad key. The docs say 403, the live API answered 401 on 8 October 2026\n5. On 429 back off without a hint. `Retry-After` is documented only for 503\n6. 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\n\n## Questions\n\n### Which is better for AI agents, OpenWeather One Call API or Tomorrow.io Weather API?\n\nOpenWeather One Call API scores 57.4 (C) on agent readiness against Tomorrow.io Weather API's 51.4 (D), and leads in 3 of 7 scored categories. Tomorrow.io Weather API leads on reliability and schema \u0026 documentation.\n\n### Do OpenWeather One Call API and Tomorrow.io Weather API need an API key?\n\nOpenWeather One Call API needs an API key. Tomorrow.io Weather API takes an API key or an OAuth sign-in.\n\n### Can an agent call OpenWeather One Call API and Tomorrow.io Weather API without installing anything?\n\nYes. OpenWeather One Call API has a hosted endpoint at https://api.openweathermap.org/data/3.0/onecall and Tomorrow.io Weather API at https://api.tomorrow.io/v4.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.json, and with the fewest tokens: https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"openweather-one-call\", \"b\": \"tomorrow-io\"}`. From a terminal: `anchor compare openweather-one-call tomorrow-io`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/openweather-one-call.json and https://www.anchorterminal.com/api/v1/tools/tomorrow-io.json\n\n## Other comparisons with OpenWeather One Call API or Tomorrow.io Weather 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- [AccuWeather Core Weather API + MCP vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/accuweather-api-vs-tomorrow-io.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- [Google Weather API (Maps Platform) vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/google-weather-api-vs-tomorrow-io.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- [Met Office Weather DataHub (Site Specific) vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/met-office-datahub-vs-tomorrow-io.md)\n- [meteoblue Weather API vs OpenWeather One Call API](https://www.anchorterminal.com/compare/meteoblue-vs-openweather-one-call.md)\n- [meteoblue Weather API vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/meteoblue-vs-tomorrow-io.md)\n- [Meteomatics Weather API vs OpenWeather One Call API](https://www.anchorterminal.com/compare/meteomatics-vs-openweather-one-call.md)\n- [Meteomatics Weather API vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/meteomatics-vs-tomorrow-io.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- [NOAA National Weather Service API (api.weather.gov) vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/nws-api-vs-tomorrow-io.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 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- [Pirate Weather vs Tomorrow.io Weather API](https://www.anchorterminal.com/compare/pirate-weather-vs-tomorrow-io.md)\n- [Tomorrow.io Weather API vs Visual Crossing Weather API](https://www.anchorterminal.com/compare/tomorrow-io-vs-visual-crossing.md)\n- [Tomorrow.io Weather API vs The Weather Company Data APIs](https://www.anchorterminal.com/compare/tomorrow-io-vs-weather-company.md)\n- [Tomorrow.io Weather API vs WeatherAPI.com](https://www.anchorterminal.com/compare/tomorrow-io-vs-weatherapi-com.md)\n- [Tomorrow.io Weather API vs Weatherbit API](https://www.anchorterminal.com/compare/tomorrow-io-vs-weatherbit.md)\n- [Tomorrow.io Weather API vs Xweather Weather API](https://www.anchorterminal.com/compare/tomorrow-io-vs-xweather.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-08", "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 Tomorrow.io Weather API", "url": "" } ], "description": "OpenWeather One Call API scores 57.4 (C) on agent readiness against Tomorrow.io Weather API's 51.4 (D), and leads in 3 of 7 scored categories. Tomorrow.io Weather API leads on reliability and schema \u0026 documentation. Both do weather current. Category scores, facts, verdicts and…", "facts": [ "OpenWeather One Call API C 57.4", "Tomorrow.io Weather API D 51.4", "scores" ], "h1": "OpenWeather One Call API vs Tomorrow.io Weather API", "image": "https://www.anchorterminal.com/assets/og/compare-openweather-one-call-vs-tomorrow-io.png", "path": "/compare/openweather-one-call-vs-tomorrow-io", "published": "2026-10-01", "section": "tools", "title": "OpenWeather One Call API vs Tomorrow.io Weather API for AI agents", "toc": null, "updated": "2026-10-08", "url": "https://www.anchorterminal.com/compare/openweather-one-call-vs-tomorrow-io" }, "tokens": { "markdown": 2700, "slim": 730 }, "version": 1 }