{
  "data": {
    "a": {
      "slug": "cronofy",
      "name": "Cronofy API",
      "vendor": "Cronofy",
      "vendorUrl": "https://www.cronofy.com",
      "kind": "http-api",
      "category": "scheduling",
      "summary": "Calendar sync and scheduling API from a UK company.",
      "url": "https://www.anchorterminal.com/tools/cronofy",
      "markdownUrl": "https://www.anchorterminal.com/tools/cronofy.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/cronofy.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/cronofy.json",
      "repo": "https://github.com/cronofy/cronofy-node",
      "license": "MIT (SDKs)",
      "transports": [
        "http",
        "streamable-http"
      ],
      "remoteUrl": "https://api.cronofy.com",
      "packages": [
        {
          "registry": "npm",
          "name": "cronofy"
        },
        {
          "registry": "pypi",
          "name": "pycronofy"
        }
      ],
      "auth": "mixed",
      "authNotes": "Each user connects through Cronofy's OAuth flow and gets an access token. Application-level calls such as Availability take the application's key as a Bearer token. The MCP server takes the `client_secret` of an internal application as a Bearer token for single-tenant use, or OAuth 2.0 for multi-tenant use.",
      "pricing": "paid",
      "pricingNotes": "Free developer account for building and testing. Emerging $819 a month billed yearly for up to 500 synced accounts, then $1.39 each a month. Growth $2,399 a month billed yearly for up to 3,000, then $0.69 each. Strategic is custom with priority support. The Meeting Agents add-on costs $0.79 an hour for 25 to 4,000 hours, with a $99 monthly minimum on its own and the first 24 hours free (https://www.cronofy.com/pricing).",
      "priceSummary": "$819 / mo",
      "where": "hosted",
      "x402": {
        "level": "no",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": 51,
        "npmWeekly": 10797,
        "pypiWeekly": 10097,
        "asOf": "2026-09-30"
      },
      "docsUrl": "https://docs.cronofy.com/developers/",
      "llmsTxt": "https://docs.cronofy.com/llms.txt",
      "capabilities": [
        "calendar.read",
        "calendar.write",
        "calendar.availability",
        "calendar.booking",
        "calendar.webhooks"
      ],
      "tags": [
        "hosted",
        "mcp",
        "llms-txt",
        "webhooks",
        "typescript",
        "python",
        "enterprise",
        "eu",
        "closed-source"
      ],
      "lastRelease": "2026-09-25",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 64.4,
        "grade": "B",
        "agentReady": false,
        "rank": 182,
        "ranked": true,
        "rankOf": 452,
        "categoryRank": 5,
        "methodology": "0.3",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 76,
          "maintenance": 56,
          "payments": 30,
          "reliability": 85,
          "schema": 58,
          "security": 60,
          "transparency": 74
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-10-01"
        },
        "negative": 0,
        "verdict": "OAuth scopes as narrow as `free_busy`, with `delete_event` separate from `create_event`. Production pricing starts at $819 a month billed yearly.",
        "strengths": [
          "OAuth scopes as narrow as `free_busy`, with `delete_event` separate from `create_event`",
          "Event writes keyed on your `event_id`, so a retried create updates instead of duplicating",
          "99.99% uptime guarantee on Emerging and Growth",
          "Retention published per data type, such as 30 days for third-party events after disconnection",
          "ISO 27001, 27018 and 27701, SOC 2 Type 2 and a public bug bounty"
        ],
        "weaknesses": [
          "Production pricing starts at $819 a month billed yearly",
          "No OpenAPI spec or security.txt",
          "The changelog has no dates and its latest entries are years old",
          "MCP server is early access with no published tool list, and single-tenant mode takes the application secret",
          "429 guidance says only to pause, with no Retry-After"
        ],
        "agentNotes": [
          "Call the data centre host the account was created in (api-uk, api-de and so on), since data never crosses regions",
          "Reuse the same `event_id` when retrying an event write, since Cronofy upserts on it",
          "Ask for `response_format` slots when you want bookable times rather than free periods",
          "On 423, ask the user to relink, since Cronofy has already emailed them",
          "Keep under 50 requests a second and 500 a minute, and pause on 429"
        ],
        "metrics": {
          "kind": "remote",
          "measured": false
        },
        "reviewCount": 2,
        "avgRating": 4,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "B",
            "methodology": "0.3",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 64.4
          }
        ],
        "editorialScores": {
          "ergonomics": 76,
          "maintenance": 56,
          "payments": 30,
          "reliability": 85,
          "schema": 58,
          "security": 60,
          "transparency": 58
        },
        "provenanceScore": 90
      },
      "connect": {
        "http": "curl -X POST https://api.cronofy.com/v1/availability \\\n  -H \"Authorization: Bearer $CRONOFY_API_KEY\" \\\n  -H \"Content-Type: application/json\" \\\n  -d '{\"participants\":[{\"members\":[{\"sub\":\"acc_5ba21743f408617d1269ea1e\"}],\"required\":\"all\"}],\"required_duration\":{\"minutes\":30},\"query_periods\":[{\"start\":\"2026-10-01T09:00:00Z\",\"end\":\"2026-10-01T17:00:00Z\"}],\"response_format\":\"slots\"}'",
        "claudeCode": "claude mcp add --transport http cronofy https://api.cronofy.com/v1/mcp_server --header \"Authorization: Bearer $CRONOFY_CLIENT_SECRET\"",
        "config": {
          "mcpServers": {
            "cronofy": {
              "headers": {
                "Authorization": "Bearer ${CRONOFY_CLIENT_SECRET}"
              },
              "url": "https://api.cronofy.com/v1/mcp_server"
            }
          }
        }
      },
      "letme": {
        "capability": "https://letme.dev/calendar.read",
        "tool": "https://letme.dev/cronofy"
      },
      "area": "everyday",
      "unitPrices": [
        {
          "item": "Emerging",
          "unit": "month",
          "usd": 819,
          "note": "Up to 500 synced accounts, billed yearly"
        },
        {
          "item": "Growth",
          "unit": "month",
          "usd": 2399,
          "note": "Up to 3,000 synced accounts, billed yearly"
        },
        {
          "item": "Extra synced account on Emerging",
          "unit": "account-month",
          "usd": 1.39
        },
        {
          "item": "Extra synced account on Growth",
          "unit": "account-month",
          "usd": 0.69
        }
      ],
      "provenance": {
        "legalEntity": "Cronofy Limited",
        "domain": "cronofy.com",
        "domainRegistered": "2014-10-06",
        "endpointOnVendorDomain": true,
        "terms": "https://docs.cronofy.com/policies/terms-of-service/",
        "privacy": "https://docs.cronofy.com/policies/privacy-notice/",
        "statusPage": "https://status.cronofy.com",
        "changelog": "https://changelog.cronofy.com",
        "securityTxt": "none",
        "checked": "2026-09-30",
        "notes": [
          "The terms (updated 24 September 2026) name Cronofy Limited, company number 07878590, 9a Beck Street, Nottingham, under the laws of England and Wales.",
          "www.cronofy.com/.well-known/security.txt returns 404.",
          "The status page lists the API, Scheduler, Meeting Agents, conferencing services and each major calendar provider as separate components."
        ],
        "score": 90
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/cronofy.json",
      "live": {
        "slug": "cronofy",
        "probe": {
          "target": "https://api.cronofy.com",
          "method": "get",
          "lastAt": "2026-10-04T23:32:45.992385715Z",
          "lastOk": true,
          "lastStatus": 404,
          "lastMs": 263,
          "authRequired": false,
          "uptime24h": 100,
          "uptime30d": 100,
          "p50ms24h": 265,
          "p95ms24h": 305,
          "samples24h": 272,
          "samples30d": 895,
          "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": 267,
              "ok": 267
            }
          ]
        },
        "vendorStatus": {
          "page": "https://status.cronofy.com",
          "indicator": "none",
          "summary": "All Systems Operational",
          "checkedAt": "2026-10-04T23:27:44.183802816Z"
        },
        "versions": [
          {
            "registry": "npm",
            "name": "cronofy",
            "version": "3.8.4",
            "seenAt": "2026-10-04T16:24:50.006903677Z"
          },
          {
            "registry": "pypi",
            "name": "pycronofy",
            "version": "2.1.1",
            "released": "2026-09-25",
            "seenAt": "2026-10-04T16:24:51.846800426Z"
          }
        ],
        "githubStars": 51,
        "npmWeekly": 13415,
        "pypiWeekly": 7328,
        "securityTxt": {
          "url": "https://cronofy.com/.well-known/security.txt",
          "state": "none",
          "checkedAt": "2026-10-04T15:16:04.962526224Z"
        },
        "llmsTxt": {
          "url": "https://docs.cronofy.com/llms.txt",
          "ok": true,
          "status": 200,
          "checkedAt": "2026-10-04T15:17:28.77497468Z"
        },
        "domain": {
          "domain": "cronofy.com",
          "registered": "2014-10-06",
          "source": "https://rdap.verisign.com/com/v1/domain/cronofy.com",
          "checkedAt": "2026-10-04T13:09:51.714116739Z"
        },
        "pages": [
          {
            "url": "https://changelog.cronofy.com",
            "kind": "changelog",
            "status": 200,
            "checkedAt": "2026-10-04T15:41:50.385949335Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "c6a5150f60a1"
          },
          {
            "url": "https://www.cronofy.com/pricing",
            "kind": "pricing",
            "status": 304,
            "checkedAt": "2026-10-04T15:49:56.536978328Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "242d022a202a"
          },
          {
            "url": "https://docs.cronofy.com/policies/privacy-notice/",
            "kind": "privacy",
            "status": 304,
            "checkedAt": "2026-10-04T15:43:31.888004345Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "e2e1ebea1a4c"
          },
          {
            "url": "https://docs.cronofy.com/policies/terms-of-service/",
            "kind": "terms",
            "status": 304,
            "checkedAt": "2026-10-04T15:43:34.034365666Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "7298fc93e38a"
          }
        ],
        "updatedAt": "2026-10-04T23:32:45.992385715Z"
      }
    },
    "b": {
      "slug": "microsoft-graph-calendar",
      "name": "Microsoft Graph Calendar API",
      "vendor": "Microsoft",
      "vendorUrl": "https://learn.microsoft.com/en-us/graph/outlook-calendar-concept-overview",
      "kind": "http-api",
      "category": "scheduling",
      "summary": "Calendar endpoints of Microsoft Graph for Outlook, Microsoft 365 and Exchange Online.",
      "url": "https://www.anchorterminal.com/tools/microsoft-graph-calendar",
      "markdownUrl": "https://www.anchorterminal.com/tools/microsoft-graph-calendar.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/microsoft-graph-calendar.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/microsoft-graph-calendar.json",
      "repo": "https://github.com/microsoftgraph/msgraph-sdk-javascript",
      "license": "MIT (SDKs)",
      "transports": [
        "http"
      ],
      "remoteUrl": "https://graph.microsoft.com/v1.0",
      "packages": [
        {
          "registry": "npm",
          "name": "@microsoft/microsoft-graph-client"
        },
        {
          "registry": "pypi",
          "name": "msgraph-sdk"
        }
      ],
      "auth": "oauth",
      "authNotes": "OAuth 2.0 tokens from Microsoft Entra ID. Delegated permissions (Calendars.Read, Calendars.ReadWrite) act as a signed-in user. Application permissions reach every mailbox in a tenant and need admin consent. Personal Outlook.com accounts work with delegated permissions.",
      "pricing": "byo-plan",
      "pricingNotes": "Calendar endpoints aren't metered. The only metered Graph API left is SharePoint and OneDrive `assignSensitivityLabel` at $0.00185 a call (https://learn.microsoft.com/en-us/graph/metered-api-list). Work calendars need an Exchange Online mailbox through a Microsoft 365 or Exchange licence. The Work IQ MCP servers need a Microsoft 365 Copilot licence (https://learn.microsoft.com/en-us/microsoft-agent-365/tooling-servers-overview).",
      "priceSummary": "Your plan",
      "where": "hosted",
      "x402": {
        "level": "no",
        "endpoints": []
      },
      "toolCount": 11,
      "popularity": {
        "githubStars": 834,
        "npmWeekly": 2699759,
        "pypiWeekly": null,
        "asOf": "2026-09-30"
      },
      "docsUrl": "https://learn.microsoft.com/en-us/graph/outlook-calendar-concept-overview",
      "openapi": "https://raw.githubusercontent.com/microsoftgraph/msgraph-metadata/master/openapi/v1.0/openapi.yaml",
      "capabilities": [
        "calendar.read",
        "calendar.write",
        "calendar.availability",
        "calendar.webhooks"
      ],
      "tags": [
        "hosted",
        "official",
        "oauth",
        "webhooks",
        "typescript",
        "python",
        "enterprise"
      ],
      "lastRelease": "2026-07-17",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 65.6,
        "grade": "B",
        "agentReady": false,
        "rank": 170,
        "ranked": true,
        "rankOf": 452,
        "categoryRank": 4,
        "methodology": "0.3",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 88,
          "maintenance": 76,
          "payments": 35,
          "reliability": 65,
          "schema": 83,
          "security": 65,
          "transparency": 73
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-10-01"
        },
        "negative": -4,
        "negativeNotes": [
          "2026-06-16: a fix for a token leak through URL userinfo host confusion was merged into msgraph-sdk-javascript and the version bumped to 3.0.8, but npm still serves 3.0.7 from September 2023 and the repository has no published advisory. Exploiting it needs an attacker-influenced URL passed to the client (https://github.com/microsoftgraph/msgraph-sdk-javascript/commit/5438ae90f50ef15d3656f0cf9c5485deee351f19, https://registry.npmjs.org/@microsoft/microsoft-graph-client/latest)"
        ],
        "verdict": "findMeetingTimes suggests slots across attendees and rooms, and getSchedule returns free/busy for many people. 4 concurrent requests per app per mailbox.",
        "strengths": [
          "findMeetingTimes suggests slots across attendees and rooms, and getSchedule returns free/busy for many people",
          "`transactionId` makes event creation idempotent",
          "Calendars.ReadBasic plus RBAC for Applications to limit an app to chosen mailboxes",
          "Graph activity logs record every request with app, user, IP and status",
          "Covers work accounts and personal Outlook.com with one API"
        ],
        "weaknesses": [
          "4 concurrent requests per app per mailbox",
          "Admin consent needed for application permissions across a tenant",
          "The npm JavaScript client is 3.0.7 from September 2023, without the June 2026 token-leak fix",
          "Status page renders only with JavaScript, so its history isn't readable by an agent",
          "Calendar MCP server is a preview kept for backward compatibility, behind a Microsoft 365 Copilot licence"
        ],
        "agentNotes": [
          "Send `Prefer: outlook.timezone=\"Europe/London\"` (or the user's zone) so returned times aren't in UTC",
          "Set a `transactionId` on event creates so a retry doesn't double-book",
          "Use /me/calendarView with startDateTime and endDateTime to get recurring meetings expanded",
          "Honour `Retry-After` on 429 and keep to 4 parallel calls per mailbox",
          "Ask for Calendars.ReadBasic when you don't need event bodies"
        ],
        "metrics": {
          "kind": "remote",
          "measured": false
        },
        "reviewCount": 2,
        "avgRating": 3,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "B",
            "methodology": "0.3",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 65.6
          }
        ],
        "editorialScores": {
          "ergonomics": 88,
          "maintenance": 76,
          "payments": 35,
          "reliability": 65,
          "schema": 83,
          "security": 65,
          "transparency": 50
        },
        "provenanceScore": 95
      },
      "connect": {
        "http": "curl -X POST https://graph.microsoft.com/v1.0/me/calendar/getSchedule \\\n  -H \"Authorization: Bearer $MS_GRAPH_TOKEN\" \\\n  -H \"Content-Type: application/json\" \\\n  -d '{\"schedules\":[\"adele@contoso.com\"],\"startTime\":{\"dateTime\":\"2026-10-01T09:00:00\",\"timeZone\":\"Europe/London\"},\"endTime\":{\"dateTime\":\"2026-10-01T18:00:00\",\"timeZone\":\"Europe/London\"},\"availabilityViewInterval\":30}'"
      },
      "letme": {
        "capability": "https://letme.dev/calendar.read",
        "tool": "https://letme.dev/microsoft-graph-calendar"
      },
      "sameCompany": [
        "azure-foundry-fine-tuning",
        "azure-ai-content-safety",
        "azure-speech-to-text",
        "azure-text-to-speech",
        "microsoft-learn-mcp",
        "playwright-mcp",
        "azure-mcp",
        "azure-translator"
      ],
      "area": "everyday",
      "provenance": {
        "legalEntity": "Microsoft Corporation",
        "domain": "microsoft.com",
        "domainRegistered": "1991-05-02",
        "domainNote": "The endpoint is on graph.microsoft.com. microsoft.com publishes a security.txt, but it passed its Expires date on 2026-09-23.",
        "endpointOnVendorDomain": true,
        "terms": "https://learn.microsoft.com/en-us/legal/microsoft-apis/terms-of-use",
        "privacy": "https://privacy.microsoft.com/en-us/privacystatement",
        "statusPage": "https://status.cloud.microsoft",
        "changelog": "https://developer.microsoft.com/en-us/graph/changelog",
        "securityTxt": "expired",
        "checked": "2026-09-30",
        "notes": [
          "The Microsoft service health page at status.cloud.microsoft needs JavaScript to show anything.",
          "The Work IQ Calendar MCP reference was last updated on 2026-09-30."
        ],
        "score": 95
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/microsoft-graph-calendar.json",
      "live": {
        "slug": "microsoft-graph-calendar",
        "probe": {
          "target": "https://graph.microsoft.com/v1.0",
          "method": "get",
          "lastAt": "2026-10-04T23:32:50.572261015Z",
          "lastOk": true,
          "lastStatus": 200,
          "lastMs": 30,
          "authRequired": false,
          "uptime24h": 100,
          "uptime30d": 100,
          "p50ms24h": 32,
          "p95ms24h": 94,
          "samples24h": 272,
          "samples30d": 895,
          "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": 267,
              "ok": 267
            }
          ]
        },
        "vendorStatus": {
          "page": "https://status.cloud.microsoft",
          "indicator": "unknown",
          "summary": "no machine-readable status found",
          "checkedAt": "2026-10-04T21:40:15.009108067Z"
        },
        "versions": [
          {
            "registry": "github",
            "name": "microsoftgraph/msgraph-sdk-javascript",
            "version": "3.0.7",
            "released": "2023-09-19",
            "seenAt": "2026-10-04T16:33:02.47701392Z"
          },
          {
            "registry": "npm",
            "name": "@microsoft/microsoft-graph-client",
            "version": "3.0.7",
            "seenAt": "2026-10-04T16:33:00.475029869Z"
          },
          {
            "registry": "pypi",
            "name": "msgraph-sdk",
            "version": "1.63.0",
            "released": "2026-09-16",
            "seenAt": "2026-10-04T16:33:01.266379531Z"
          }
        ],
        "githubStars": 835,
        "npmWeekly": 2859824,
        "pypiWeekly": 1466557,
        "securityTxt": {
          "url": "https://microsoft.com/.well-known/security.txt",
          "state": "expired",
          "expires": "2026-09-23T16:00:00.000Z",
          "checkedAt": "2026-10-04T15:16:01.36832038Z"
        },
        "domain": {
          "domain": "microsoft.com",
          "registered": "1991-05-02",
          "source": "https://rdap.verisign.com/com/v1/domain/microsoft.com",
          "checkedAt": "2026-10-04T13:04:13.488857536Z"
        },
        "pages": [
          {
            "url": "https://developer.microsoft.com/en-us/graph/changelog",
            "kind": "changelog",
            "status": 200,
            "checkedAt": "2026-10-04T15:42:37.57775284Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "7bb1f9551c94"
          },
          {
            "url": "https://learn.microsoft.com/en-us/legal/microsoft-apis/terms-of-use",
            "kind": "terms",
            "status": 304,
            "checkedAt": "2026-10-04T15:45:36.925612719Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "1a1ee1c20d9a"
          }
        ],
        "updatedAt": "2026-10-04T23:32:50.572261015Z"
      }
    },
    "summary": "Microsoft Graph Calendar API has a score of 65.6 (B) against Cronofy API's 64.4 (B). Both do calendar read. The largest gap is schema \u0026 documentation, 25 points."
  },
  "kind": "anchor.page",
  "links": {
    "api": "https://www.anchorterminal.com/api/v1/index.json",
    "html": "https://www.anchorterminal.com/compare/cronofy-vs-microsoft-graph-calendar",
    "json": "https://www.anchorterminal.com/compare/cronofy-vs-microsoft-graph-calendar.json",
    "llms": "https://www.anchorterminal.com/llms.txt",
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  "markdown": "Microsoft Graph Calendar API has a score of 65.6 (B) against Cronofy API's 64.4 (B). Both do calendar read. The largest gap is schema \u0026 documentation, 25 points.\n\n- Cronofy API: grade B, 64.4/100, rank #182 of 452. Markdown https://www.anchorterminal.com/tools/cronofy.md · JSON https://www.anchorterminal.com/api/v1/tools/cronofy.json\n- Microsoft Graph Calendar API: grade B, 65.6/100, rank #170 of 452. Markdown https://www.anchorterminal.com/tools/microsoft-graph-calendar.md · JSON https://www.anchorterminal.com/api/v1/tools/microsoft-graph-calendar.json\n\n## Which one, for what\n\nPick Cronofy API for reliability (+20).\n\nPick Microsoft Graph Calendar API for schema \u0026 documentation (+25), agent ergonomics (+12), security \u0026 auth (+5), payments \u0026 pricing (+5), maintenance \u0026 community (+20).\n\n## Score by category\n\n| Category | Weight | Cronofy API | Microsoft Graph Calendar API | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 85 | 65 | Cronofy API +20 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 58 | 83 | Microsoft Graph Calendar API +25 |\n| Agent ergonomics | 13% (16.2 this run) | 76 | 88 | Microsoft Graph Calendar API +12 |\n| Security \u0026 auth | 14% (17.5 this run) | 60 | 65 | Microsoft Graph Calendar API +5 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 30 | 35 | Microsoft Graph Calendar API +5 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 56 | 76 | Microsoft Graph Calendar API +20 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 74 | 73 | Cronofy API +1 |\n| Negative events | ≤15 | 0 | -4 | |\n| **Total** | | **64.4 · B** | **65.6 · B** | |\n\n## Facts side by side\n\n| Fact | Cronofy API | Microsoft Graph Calendar API |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Cronofy | Microsoft |\n| Hosted endpoint | `https://api.cronofy.com` | `https://graph.microsoft.com/v1.0` |\n| Transports | HTTP, Streamable HTTP | HTTP |\n| Auth | OAuth or key | OAuth |\n| Pricing | Paid | Your plan |\n| x402 | no | no |\n| Licence | MIT (SDKs) | MIT (SDKs) |\n| Tools exposed | none | 11 |\n| Context cost (tools/list) | n/a | n/a |\n| p95 latency | not measured yet | not measured yet |\n| Availability (30d) | not measured yet | not measured yet |\n| Read-only variant documented | no | no |\n| llms.txt | yes | no |\n| MCP registry | not listed | not listed |\n| Last release | 2026-09-25 | 2026-07-17 |\n| Popularity | 51 stars, 11k npm/wk, 10k PyPI/wk | 834 stars, 2.7M npm/wk |\n| Agent reviews | 4/5 (2) | 3/5 (2) |\n\n## Verdicts\n\n**Cronofy API.** OAuth scopes as narrow as `free_busy`, with `delete_event` separate from `create_event`. Production pricing starts at $819 a month billed yearly.\n\n**Microsoft Graph Calendar API.** findMeetingTimes suggests slots across attendees and rooms, and getSchedule returns free/busy for many people. 4 concurrent requests per app per mailbox.\n\n## Before you call either\n\n### Cronofy API\n\n1. Call the data centre host the account was created in (api-uk, api-de and so on), since data never crosses regions\n2. Reuse the same `event_id` when retrying an event write, since Cronofy upserts on it\n3. Ask for `response_format` slots when you want bookable times rather than free periods\n4. On 423, ask the user to relink, since Cronofy has already emailed them\n5. Keep under 50 requests a second and 500 a minute, and pause on 429\n\n### Microsoft Graph Calendar API\n\n1. Send `Prefer: outlook.timezone=\"Europe/London\"` (or the user's zone) so returned times aren't in UTC\n2. Set a `transactionId` on event creates so a retry doesn't double-book\n3. Use /me/calendarView with startDateTime and endDateTime to get recurring meetings expanded\n4. Honour `Retry-After` on 429 and keep to 4 parallel calls per mailbox\n5. Ask for Calendars.ReadBasic when you don't need event bodies\n\n## Other comparisons with Cronofy API or Microsoft Graph Calendar API\n\n- [Apiroc Unified Calendar API vs Cronofy API](https://www.anchorterminal.com/compare/apiroc-vs-cronofy.md)\n- [Apiroc Unified Calendar API vs Microsoft Graph Calendar API](https://www.anchorterminal.com/compare/apiroc-vs-microsoft-graph-calendar.md)\n- [Cal.com API v2 + MCP vs Cronofy API](https://www.anchorterminal.com/compare/cal-com-vs-cronofy.md)\n- [Cal.com API v2 + MCP vs Microsoft Graph Calendar API](https://www.anchorterminal.com/compare/cal-com-vs-microsoft-graph-calendar.md)\n- [Calendly API + MCP vs Cronofy API](https://www.anchorterminal.com/compare/calendly-vs-cronofy.md)\n- [Calendly API + MCP vs Microsoft Graph Calendar API](https://www.anchorterminal.com/compare/calendly-vs-microsoft-graph-calendar.md)\n- [Cronofy API vs Google Calendar API](https://www.anchorterminal.com/compare/cronofy-vs-google-calendar-api.md)\n- [Cronofy API vs Nylas Calendar and Scheduler API](https://www.anchorterminal.com/compare/cronofy-vs-nylas-calendar.md)\n- [Google Calendar API vs Microsoft Graph Calendar API](https://www.anchorterminal.com/compare/google-calendar-api-vs-microsoft-graph-calendar.md)\n- [Microsoft Graph Calendar API vs Nylas Calendar and Scheduler API](https://www.anchorterminal.com/compare/microsoft-graph-calendar-vs-nylas-calendar.md)\n",
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        "name": "Cronofy API vs Microsoft Graph Calendar API",
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    "description": "Microsoft Graph Calendar API has a score of 65.6 (B) against Cronofy API's 64.4 (B). Both do calendar read. The largest gap is schema \u0026 documentation, 25 points. Category scores, facts, verdicts and agent notes side by side.",
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      "Cronofy API B 64.4",
      "Microsoft Graph Calendar API B 65.6",
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    "h1": "Cronofy API vs Microsoft Graph Calendar API",
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    "section": "tools",
    "title": "Cronofy API vs Microsoft Graph Calendar API for AI agents",
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