{
  "data": {
    "a": {
      "slug": "emailengine",
      "name": "EmailEngine",
      "vendor": "Postal Systems OÜ",
      "vendorUrl": "https://emailengine.app",
      "kind": "http-api",
      "category": "mailbox-access",
      "summary": "EmailEngine is self-hosted software from Postal Systems that puts one REST API over Gmail, Microsoft 365 and IMAP mailboxes, with webhooks for new mail and a beta MCP server. The owner runs it with Redis.",
      "url": "https://www.anchorterminal.com/tools/emailengine",
      "markdownUrl": "https://www.anchorterminal.com/tools/emailengine.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/emailengine.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/emailengine.json",
      "repo": "https://github.com/postalsys/emailengine",
      "license": "Source available under the EmailEngine licence agreement, version 2.1 of 17 October 2023. Not open source. The PHP SDK is MIT",
      "transports": [
        "http"
      ],
      "packages": [
        {
          "registry": "npm",
          "name": "emailengine-app"
        },
        {
          "registry": "oci",
          "name": "postalsys/emailengine"
        },
        {
          "registry": "packagist",
          "name": "postalsys/emailengine-php"
        }
      ],
      "auth": "api-key",
      "authNotes": "Access is granted by whoever runs the instance, with no vendor approval or app review. Every request takes a 64-character token as `Authorization: Bearer`, or in the `access_token` query parameter. Tokens are created in the admin interface, with the CLI (`emailengine tokens issue`) or through POST /v1/tokens, which only mints tokens bound to one account or narrowed by a permissions record. A token carries scopes (`*`, api, metrics, smtp, imap-proxy, mcp, mcp-manage), an optional account binding, allowlists of actions (read, write, send, destructive) and groups, an IP allowlist, an expiry and a rate limit. The beta MCP endpoint also has an optional built-in OAuth 2.1 server. Mailboxes are connected with the operator's own Google and Microsoft OAuth2 apps, service accounts or IMAP passwords, which stay inside the instance.",
      "pricing": "paid",
      "pricingNotes": "$1,450 or EUR 1,200 a year, excluding VAT, for unlimited mailboxes, instances and API calls, bought with an account at postalsys.com. Every install can start a 14-day trial with full functionality from its own dashboard, with no sign-up and no card, so an agent's owner can start without a contract. When the trial ends the instance stops processing accounts until a licence key is added. A perpetual licence is sold through sales with no public price. The owner also pays for the server and Redis (https://emailengine.app/, https://postalsys.com/plans, checked 2026-10-08).",
      "priceSummary": "$120.83 / mo",
      "where": "local",
      "x402": {
        "level": "no",
        "evidence": "No x402, MPP or L402 on emailengine.app, in the documentation or in the OpenAPI spec (checked 2026-10-08). Licences are bought by card at postalsys.com, with Stripe named as the payment processor.",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": 2237,
        "npmWeekly": 388,
        "pypiWeekly": null,
        "asOf": "2026-10-08"
      },
      "docsUrl": "https://learn.emailengine.app/",
      "llmsTxt": "https://emailengine.app/llms.txt",
      "openapi": "https://go.emailengine.app/swagger.json",
      "capabilities": [
        "mailbox.read",
        "mailbox.search",
        "mailbox.send",
        "mailbox.drafts",
        "mailbox.sync"
      ],
      "tags": [
        "self-hosted",
        "source-available",
        "paid",
        "trial",
        "api-key",
        "openapi",
        "llms-txt",
        "mcp",
        "webhooks",
        "imap",
        "gmail",
        "microsoft-365",
        "docker",
        "nodejs",
        "php"
      ],
      "lastRelease": "2026-10-05",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 71.4,
        "grade": "BB",
        "agentReady": true,
        "rank": 106,
        "ranked": true,
        "rankOf": 629,
        "categoryRank": 3,
        "methodology": "0.4",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 80,
          "maintenance": 81,
          "payments": 40,
          "reliability": 79,
          "schema": 91,
          "security": 71,
          "transparency": 72
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-10-08"
        },
        "negative": -3,
        "negativeNotes": [
          "27 September 2026. Version 2.81.2, a patch release, removed the `bounces` field from the message list, message details and messageNew payloads, listed under bug fixes with no earlier notice found in the changelog. The bounce still arrives through the messageBounce webhook, and the entry is documented, so the smallest deduction applies (https://github.com/postalsys/emailengine/blob/master/CHANGELOG.md)"
        ],
        "verdict": "A self-hosted REST API over Gmail, Microsoft 365 and IMAP, with a public OpenAPI 3.0 spec and tokens that can be bound to one account, limited by action and group, and rate limited. It needs a server, Redis and a $1,450 yearly licence after a 14-day trial, and the MCP endpoint is a beta, off by default.",
        "bestFor": "A team that must keep mailbox access on its own infrastructure, has many mailboxes across Gmail, Microsoft 365 and IMAP, and can run a server and Redis.",
        "strengths": [
          "Public OpenAPI 3.0 spec for version 2.82.2 with 82 operations, plus llms.txt on both sites and a capabilities.json manifest",
          "Tokens can be bound to one account, narrowed by action and group, limited by IP range, expiry and rate, and are stored only as SHA-256 hashes",
          "Idempotency-Key header on both send routes, and 429 responses carry Retry-After and a ttl field",
          "Ten tagged releases between 7 September and 5 October 2026, and the last eight test runs on master passed",
          "Written prompt-injection guidance, with MCP mail access set to none by default and message bodies returned as sanitised HTML"
        ],
        "weaknesses": [
          "Not open source. Running it beyond the 14-day trial needs a subscription at $1,450 or EUR 1,200 a year",
          "The owner has to run a server and Redis. There is no hosted service, status page or SLA",
          "The MCP endpoint is labelled beta, is off by default, and its tool set may change between releases",
          "A token may also travel in the `access_token` query parameter, and API authentication can be switched off in settings",
          "Version 2.81.2, a patch release, removed the `bounces` field from message responses, and 2.82.0 removed the Document Store in a minor release",
          "One maintainer, no guaranteed support response time, and issues are disabled on the GitHub repository per the GitHub API"
        ],
        "agentNotes": [
          "Ask the operator for a token bound to one account with a permissions record. Mint more with POST /v1/tokens, which refuses instance-wide tokens without one",
          "Send the token in the Authorization header, not the `access_token` query parameter, so it stays out of proxy logs",
          "Page with `cursor` from `nextPageCursor`. `page` works only on IMAP accounts, and search covers one folder unless `path` is `\\All` on Gmail or Microsoft Graph",
          "Set an Idempotency-Key header on POST /v1/account/{account}/submit. A 2xx means queued, so follow the result through the outbox or the messageSent and messageFailed webhooks",
          "Treat message text as untrusted. For MCP, the operator must enable the endpoint first and mail access starts at none"
        ],
        "metrics": {
          "kind": "local",
          "measured": false
        },
        "reviewCount": 0,
        "avgRating": 0,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "BB",
            "methodology": "0.4",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 71.4
          }
        ],
        "editorialScores": {
          "ergonomics": 80,
          "maintenance": 81,
          "payments": 40,
          "reliability": 79,
          "schema": 91,
          "security": 71,
          "transparency": 68
        },
        "provenanceScore": 76
      },
      "connect": {
        "install": "curl -LO https://go.emailengine.app/docker-compose.yml\ndocker compose up -d",
        "http": "curl \"https://emailengine.example.com/v1/account/user@example.com/messages?path=INBOX\u0026page=0\u0026pageSize=50\" \\\n  -H \"Authorization: Bearer YOUR_ACCESS_TOKEN\"",
        "claudeCode": "claude mcp add --transport http emailengine https://emailengine.example.com/mcp \\\n  --header \"Authorization: Bearer YOUR_ACCESS_TOKEN\"",
        "config": {
          "mcpServers": {
            "emailengine": {
              "headers": {
                "Authorization": "Bearer YOUR_ACCESS_TOKEN"
              },
              "type": "http",
              "url": "https://emailengine.example.com/mcp"
            }
          }
        }
      },
      "letme": {
        "capability": "https://letme.dev/mailbox.read",
        "tool": "https://letme.dev/emailengine"
      },
      "area": "communication",
      "unitPrices": [
        {
          "item": "EmailEngine subscription, $1,450 billed yearly",
          "unit": "month",
          "usd": 120.83,
          "note": "unlimited mailboxes, instances and API calls, VAT excluded, 14-day trial without a card"
        }
      ],
      "provenance": {
        "legalEntity": "Postal Systems OÜ, Narva mnt 5, 10117 Tallinn, Estonia, registry code 14971894",
        "domain": "emailengine.app",
        "domainRegistered": "2021-07-28",
        "endpointOnVendorDomain": null,
        "terms": "https://postalsys.com/tos",
        "privacy": "https://emailengine.app/privacy-policy",
        "statusPage": "",
        "changelog": "https://github.com/postalsys/emailengine/blob/master/CHANGELOG.md",
        "securityTxt": "valid",
        "checked": "2026-10-08",
        "notes": [
          "The about page names Postal Systems OÜ at Narva mnt 5, 10117 Tallinn, with registry code 14971894 and VAT number EE102255902, and says the company is run by one person.",
          "RDAP for emailengine.app shows registration on 28 July 2021 through Namecheap.",
          "emailengine.app/.well-known/security.txt is PGP-signed, expires on 1 June 2027 and points to GitHub private advisories and SECURITY.md. postalsys.com has its own security.txt with no Expires field.",
          "The terms of service at postalsys.com/tos are dated 14 May 2020 and cover the subscription. The software licence is the EmailEngine licence agreement, version 2.1 of 17 October 2023, governed by Estonian law.",
          "The privacy policy at emailengine.app/privacy-policy has an effective date of 29 July 2026 and covers the website and the licence account, with Stripe named for payments.",
          "The API runs on the owner's instance, so there is no vendor endpoint and no status page."
        ],
        "score": 76
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/emailengine.json",
      "live": {
        "slug": "emailengine",
        "versions": [
          {
            "registry": "github",
            "name": "postalsys/emailengine",
            "version": "v2.83.0",
            "released": "2026-10-08",
            "seenAt": "2026-10-08T16:10:38.546496352Z"
          },
          {
            "registry": "npm",
            "name": "emailengine-app",
            "version": "2.83.0",
            "seenAt": "2026-10-08T16:10:36.788101811Z"
          }
        ],
        "githubStars": 2238,
        "npmWeekly": 388,
        "securityTxt": {
          "url": "https://emailengine.app/.well-known/security.txt",
          "state": "valid",
          "expires": "2027-06-01T00:00:00.000Z",
          "checkedAt": "2026-10-08T15:39:10.386155427Z"
        },
        "pages": [
          {
            "url": "https://raw.githubusercontent.com/postalsys/emailengine/master/CHANGELOG.md",
            "kind": "changelog",
            "status": 200,
            "checkedAt": "2026-10-08T18:24:39.774413238Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "92032edad8ba"
          },
          {
            "url": "https://emailengine.app/privacy-policy",
            "kind": "privacy",
            "status": 200,
            "checkedAt": "2026-10-08T18:20:06.567354333Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "bf031c33ef50"
          },
          {
            "url": "https://postalsys.com/tos",
            "kind": "terms",
            "status": 200,
            "checkedAt": "2026-10-08T18:23:11.919567662Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "cb7a76a9cb6a"
          }
        ],
        "updatedAt": "2026-10-08T18:24:39.774413238Z"
      }
    },
    "answer": "EmailEngine scores 71.4 (BB) on agent readiness against Outlook Mail (Microsoft Graph)'s 66.3 (B), and leads in 3 of 7 scored categories.",
    "b": {
      "slug": "outlook-mail-graph",
      "name": "Outlook Mail (Microsoft Graph)",
      "vendor": "Microsoft",
      "vendorUrl": "https://learn.microsoft.com/en-us/graph/api/resources/mail-api-overview",
      "kind": "http-api",
      "category": "mailbox-access",
      "summary": "Mail endpoints of Microsoft Graph for Outlook, Microsoft 365 and Exchange Online mailboxes. An app reads, searches, drafts, sends and files messages over REST with OAuth tokens from Microsoft Entra ID.",
      "url": "https://www.anchorterminal.com/tools/outlook-mail-graph",
      "markdownUrl": "https://www.anchorterminal.com/tools/outlook-mail-graph.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/outlook-mail-graph.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/outlook-mail-graph.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, after a person registers an app. No app review by Microsoft was found for mail permissions. Delegated permissions (Mail.ReadBasic, Mail.Read, Mail.ReadWrite, Mail.Send) act as a signed-in user and need only that user's consent. Application permissions reach every mailbox in a tenant, need admin consent, and can be limited to chosen mailboxes with RBAC for Applications in Exchange Online. Personal Outlook.com accounts work with delegated permissions.",
      "pricing": "byo-plan",
      "pricingNotes": "Mail calls aren't metered. The only metered Graph API is SharePoint and OneDrive `assignSensitivityLabel` at $0.00185 a call (https://learn.microsoft.com/en-us/graph/metered-api-list). A work mailbox needs an Exchange Online or Microsoft 365 licence, and Microsoft's plan price page refused our reader on 8 October 2026. A free personal Outlook.com account lets an agent start without a contract. The Microsoft 365 developer programme sandbox is free only to members who qualify, such as Visual Studio subscribers. The Mail MCP server needs a Microsoft 365 Copilot licence.",
      "priceSummary": "Your plan",
      "where": "hosted",
      "x402": {
        "level": "no",
        "evidence": "No x402, MPP or L402 in the Graph mail reference or the metered API list (checked 2026-10-08).",
        "endpoints": []
      },
      "toolCount": 10,
      "popularity": {
        "githubStars": 835,
        "npmWeekly": 2882852,
        "pypiWeekly": 1578201,
        "asOf": "2026-10-08"
      },
      "docsUrl": "https://learn.microsoft.com/en-us/graph/api/resources/mail-api-overview",
      "openapi": "https://raw.githubusercontent.com/microsoftgraph/msgraph-metadata/master/openapi/v1.0/openapi.yaml",
      "capabilities": [
        "mailbox.read",
        "mailbox.search",
        "mailbox.send",
        "mailbox.drafts",
        "mailbox.sync"
      ],
      "tags": [
        "hosted",
        "official",
        "oauth",
        "openapi",
        "webhooks",
        "typescript",
        "python",
        "enterprise"
      ],
      "lastRelease": "2026-10-06",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 66.3,
        "grade": "B",
        "agentReady": false,
        "rank": 221,
        "ranked": true,
        "rankOf": 629,
        "categoryRank": 4,
        "methodology": "0.4",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 81,
          "maintenance": 76,
          "payments": 35,
          "reliability": 60,
          "schema": 93,
          "security": 71,
          "transparency": 75
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "medium",
          "date": "2026-10-08"
        },
        "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 on 8 October 2026 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": "Delegated permissions split reading without bodies (Mail.ReadBasic), full reading, writing and sending, and delta queries and change notifications keep a local copy in step. sendMail takes no idempotency key and returns 202 before delivery, and each app is held to four concurrent requests per mailbox.",
        "bestFor": "Agents working in Microsoft 365 or Outlook.com mailboxes that need scoped reading, drafting, sending and incremental sync.",
        "strengths": [
          "Mail.ReadBasic reads messages without body, preview or attachments, and Mail.Send is separate from Mail.ReadWrite",
          "Delta queries per folder and change notifications with `missed` and `subscriptionRemoved` lifecycle events",
          "`$select`, `$top` (1 to 1,000, default 10), `bodyPreview` and `Prefer: outlook.body-content-type=\"text\"` keep responses small",
          "Published policy of at least 24 months' notice before a v1.0 API is removed",
          "Covers work accounts and personal Outlook.com accounts, with every reference page also served as Markdown"
        ],
        "weaknesses": [
          "sendMail has no idempotency key and answers 202 Accepted before delivery, so a retried send can go out twice",
          "Four concurrent requests and 10,000 requests per 10 minutes for each app and mailbox pair",
          "No prompt-injection guidance found in the mail reference or the Mail MCP reference, though message bodies come from outside senders",
          "The npm JavaScript client is 3.0.7 from September 2023, without the June 2026 token-leak fix",
          "The Mail MCP server is a preview kept for backward compatibility, behind a Microsoft 365 Copilot licence"
        ],
        "agentNotes": [
          "Create a draft with POST /me/messages, then send it with /send. A retried sendMail can send the message twice",
          "Send `Prefer: IdType=\"ImmutableId\"` on every request, or message IDs change when a message moves folder",
          "Use `$select` and `Prefer: outlook.body-content-type=\"text\"`. List messages returns HTML bodies and 10 messages a page by default",
          "Honour `Retry-After` on 429 and keep to four parallel calls per mailbox. Batches of up to 20 requests are throttled per request",
          "Treat message bodies as untrusted input, and ask for Mail.ReadBasic when the task doesn't need bodies"
        ],
        "metrics": {
          "kind": "remote",
          "measured": false
        },
        "reviewCount": 0,
        "avgRating": 0,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "medium",
            "grade": "B",
            "methodology": "0.4",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 66.3
          }
        ],
        "editorialScores": {
          "ergonomics": 81,
          "maintenance": 76,
          "payments": 35,
          "reliability": 60,
          "schema": 93,
          "security": 71,
          "transparency": 65
        },
        "provenanceScore": 85
      },
      "connect": {
        "http": "curl \"https://graph.microsoft.com/v1.0/me/messages?\\$select=from,subject\" \\\n  -H \"Authorization: Bearer $MS_GRAPH_TOKEN\""
      },
      "letme": {
        "capability": "https://letme.dev/mailbox.read",
        "tool": "https://letme.dev/outlook-mail-graph"
      },
      "sameCompany": [
        "azure-foundry-fine-tuning",
        "azure-ai-content-safety",
        "azure-speech-to-text",
        "azure-text-to-speech",
        "microsoft-agent-framework",
        "microsoft-execution-containers",
        "microsoft-entra-agent-id",
        "azure-key-vault",
        "azure-devops-mcp",
        "microsoft-learn-mcp",
        "playwright-mcp",
        "azure-mcp",
        "azure-translator",
        "microsoft-graph-calendar",
        "dynamics-365-sales",
        "microsoft-advertising-api",
        "microsoft-excel-graph"
      ],
      "area": "communication",
      "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": "2026-10-08",
        "notes": [
          "The Microsoft service health page at status.cloud.microsoft needs JavaScript to show anything.",
          "The Microsoft APIs terms of use say they were last updated in October 2025.",
          "privacy.microsoft.com answered our reader with 403 on 8 October 2026, so the privacy URL follows the Microsoft Graph calendar listing and wasn't reread.",
          "RDAP for microsoft.com gives a registration date of 1991-05-02."
        ],
        "score": 85
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/outlook-mail-graph.json",
      "live": {
        "slug": "outlook-mail-graph",
        "probe": {
          "target": "https://graph.microsoft.com/v1.0",
          "method": "get",
          "lastAt": "2026-10-08T18:20:36.817208295Z",
          "lastOk": true,
          "lastStatus": 200,
          "lastMs": 2,
          "authRequired": false,
          "uptime24h": 100,
          "uptime30d": 100,
          "p50ms24h": 5,
          "p95ms24h": 30,
          "samples24h": 33,
          "samples30d": 33,
          "days": [
            {
              "date": "2026-10-08",
              "probes": 33,
              "ok": 33
            }
          ]
        },
        "versions": [
          {
            "registry": "github",
            "name": "microsoftgraph/msgraph-sdk-javascript",
            "version": "3.0.7",
            "released": "2023-09-19",
            "seenAt": "2026-10-08T16:24:30.348454398Z"
          },
          {
            "registry": "npm",
            "name": "@microsoft/microsoft-graph-client",
            "version": "3.0.7",
            "seenAt": "2026-10-08T16:24:29.99296352Z"
          },
          {
            "registry": "pypi",
            "name": "msgraph-sdk",
            "version": "1.64.0",
            "released": "2026-10-06",
            "seenAt": "2026-10-08T16:24:30.234677595Z"
          }
        ],
        "githubStars": 835,
        "npmWeekly": 2882852,
        "pypiWeekly": 1578201,
        "securityTxt": {
          "url": "https://microsoft.com/.well-known/security.txt",
          "state": "expired",
          "expires": "2026-09-23T16:00:00.000Z",
          "checkedAt": "2026-10-08T15:39:08.216544687Z"
        },
        "updatedAt": "2026-10-08T18:20:36.817208295Z"
      }
    },
    "facts": [
      {
        "a": "HTTP API",
        "b": "HTTP API",
        "name": "Kind"
      },
      {
        "a": "Postal Systems OÜ",
        "b": "Microsoft",
        "name": "Vendor"
      },
      {
        "a": "no (local only)",
        "b": "https://graph.microsoft.com/v1.0",
        "name": "Hosted endpoint"
      },
      {
        "a": "HTTP",
        "b": "HTTP",
        "name": "Transports"
      },
      {
        "a": "API key",
        "b": "OAuth",
        "name": "Auth"
      },
      {
        "a": "Paid",
        "b": "Your plan",
        "name": "Pricing"
      },
      {
        "a": "no",
        "b": "no",
        "name": "x402"
      },
      {
        "a": "Source available under the EmailEngine licence agreement, version 2.1 of 17 October 2023. Not open source. The PHP SDK is MIT",
        "b": "MIT (SDKs)",
        "name": "Licence"
      },
      {
        "a": "none",
        "b": "10",
        "name": "Tools exposed"
      },
      {
        "a": "no",
        "b": "no",
        "name": "Read-only variant documented"
      },
      {
        "a": "yes",
        "b": "no",
        "name": "llms.txt"
      },
      {
        "a": "2026-10-05",
        "b": "2026-10-06",
        "name": "Last release"
      },
      {
        "a": "no date given",
        "b": "2025-10-01",
        "name": "Terms last updated"
      },
      {
        "a": "no date given",
        "b": "2026-09-01",
        "name": "Privacy policy last updated"
      },
      {
        "a": "not found in the text",
        "b": "yes",
        "name": "Customer content may train models"
      },
      {
        "a": "yes",
        "b": "yes",
        "name": "Terms restrict automated access"
      },
      {
        "a": "not found in the text",
        "b": "yes",
        "name": "Terms restrict benchmarking"
      },
      {
        "a": "yes",
        "b": "yes",
        "name": "Terms or service can change without notice"
      },
      {
        "a": "not found in the text",
        "b": "not found in the text",
        "name": "Arbitration or class-action waiver"
      },
      {
        "a": "2.2k stars, 388 npm/wk",
        "b": "835 stars, 2.9M npm/wk, 1.6M PyPI/wk",
        "name": "Popularity"
      }
    ],
    "faq": [
      {
        "answer": "EmailEngine scores 71.4 (BB) on agent readiness against Outlook Mail (Microsoft Graph)'s 66.3 (B), and leads in 3 of 7 scored categories.",
        "question": "Which is better for AI agents, EmailEngine or Outlook Mail (Microsoft Graph)?"
      },
      {
        "answer": "EmailEngine needs an API key. Outlook Mail (Microsoft Graph) uses an OAuth sign-in.",
        "question": "Do EmailEngine and Outlook Mail (Microsoft Graph) need an API key?"
      },
      {
        "answer": "No hosted endpoint is listed for EmailEngine. Outlook Mail (Microsoft Graph) has a hosted endpoint at https://graph.microsoft.com/v1.0.",
        "question": "Can an agent call EmailEngine and Outlook Mail (Microsoft Graph) without installing anything?"
      }
    ],
    "goodFor": [
      {
        "aheadOn": [
          "Reliability, 79 against 60",
          "Payments \u0026 pricing, 40 against 35",
          "Maintenance \u0026 community, 81 against 76"
        ],
        "also": [
          "Agent-ready, a grade of BB or better"
        ],
        "goodFor": "A team that must keep mailbox access on its own infrastructure, has many mailboxes across Gmail, Microsoft 365 and IMAP, and can run a server and Redis.",
        "slug": "emailengine",
        "watchFor": "Not open source. Running it beyond the 14-day trial needs a subscription at $1,450 or EUR 1,200 a year"
      },
      {
        "aheadOn": null,
        "also": [
          "A hosted endpoint, with nothing to install"
        ],
        "goodFor": "Agents working in Microsoft 365 or Outlook.com mailboxes that need scoped reading, drafting, sending and incremental sync.",
        "slug": "outlook-mail-graph",
        "watchFor": "sendMail has no idempotency key and answers 202 Accepted before delivery, so a retried send can go out twice"
      }
    ],
    "job": {
      "capability": "mailbox.read",
      "name": "Mailbox read"
    },
    "others": [
      {
        "json": "https://www.anchorterminal.com/compare/emailengine-vs-gmail-api.json",
        "title": "EmailEngine vs Gmail API",
        "url": "https://www.anchorterminal.com/compare/emailengine-vs-gmail-api"
      },
      {
        "json": "https://www.anchorterminal.com/compare/emailengine-vs-nylas-email.json",
        "title": "EmailEngine vs Nylas Email API",
        "url": "https://www.anchorterminal.com/compare/emailengine-vs-nylas-email"
      },
      {
        "json": "https://www.anchorterminal.com/compare/emailengine-vs-unipile.json",
        "title": "EmailEngine vs Unipile",
        "url": "https://www.anchorterminal.com/compare/emailengine-vs-unipile"
      },
      {
        "json": "https://www.anchorterminal.com/compare/gmail-api-vs-outlook-mail-graph.json",
        "title": "Gmail API vs Outlook Mail (Microsoft Graph)",
        "url": "https://www.anchorterminal.com/compare/gmail-api-vs-outlook-mail-graph"
      },
      {
        "json": "https://www.anchorterminal.com/compare/nylas-email-vs-outlook-mail-graph.json",
        "title": "Nylas Email API vs Outlook Mail (Microsoft Graph)",
        "url": "https://www.anchorterminal.com/compare/nylas-email-vs-outlook-mail-graph"
      },
      {
        "json": "https://www.anchorterminal.com/compare/outlook-mail-graph-vs-unipile.json",
        "title": "Outlook Mail (Microsoft Graph) vs Unipile",
        "url": "https://www.anchorterminal.com/compare/outlook-mail-graph-vs-unipile"
      }
    ],
    "scores": [
      {
        "by": 19,
        "edge": "emailengine",
        "emailengine": 79,
        "key": "reliability",
        "name": "Reliability",
        "outlook-mail-graph": 60,
        "weight": 16
      },
      {
        "key": "performance",
        "name": "Performance",
        "pending": true,
        "weight": 10
      },
      {
        "by": 2,
        "edge": "outlook-mail-graph",
        "emailengine": 91,
        "key": "schema",
        "name": "Schema \u0026 documentation",
        "outlook-mail-graph": 93,
        "weight": 13
      },
      {
        "by": 1,
        "edge": "outlook-mail-graph",
        "emailengine": 80,
        "key": "ergonomics",
        "name": "Agent ergonomics",
        "outlook-mail-graph": 81,
        "weight": 13
      },
      {
        "by": 0,
        "edge": "",
        "emailengine": 71,
        "key": "security",
        "name": "Security \u0026 auth",
        "outlook-mail-graph": 71,
        "weight": 14
      },
      {
        "by": 5,
        "edge": "emailengine",
        "emailengine": 40,
        "key": "payments",
        "name": "Payments \u0026 pricing",
        "outlook-mail-graph": 35,
        "weight": 10
      },
      {
        "key": "tasks",
        "name": "Task success",
        "pending": true,
        "weight": 10
      },
      {
        "by": 5,
        "edge": "emailengine",
        "emailengine": 81,
        "key": "maintenance",
        "name": "Maintenance \u0026 community",
        "outlook-mail-graph": 76,
        "weight": 7
      },
      {
        "by": 3,
        "edge": "outlook-mail-graph",
        "emailengine": 72,
        "key": "transparency",
        "name": "Transparency \u0026 trust",
        "outlook-mail-graph": 75,
        "weight": 7
      }
    ],
    "summary": "EmailEngine scores 71.4 (BB) on agent readiness against Outlook Mail (Microsoft Graph)'s 66.3 (B), and leads in 3 of 7 scored categories. Both do mailbox read.",
    "verdicts": {
      "emailengine": "A self-hosted REST API over Gmail, Microsoft 365 and IMAP, with a public OpenAPI 3.0 spec and tokens that can be bound to one account, limited by action and group, and rate limited. It needs a server, Redis and a $1,450 yearly licence after a 14-day trial, and the MCP endpoint is a beta, off by default.",
      "outlook-mail-graph": "Delegated permissions split reading without bodies (Mail.ReadBasic), full reading, writing and sending, and delta queries and change notifications keep a local copy in step. sendMail takes no idempotency key and returns 202 before delivery, and each app is held to four concurrent requests per mailbox."
    }
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  "markdown": "EmailEngine scores 71.4 (BB) on agent readiness against Outlook Mail (Microsoft Graph)'s 66.3 (B), and leads in 3 of 7 scored categories. Both do mailbox read.\n\n- EmailEngine: grade BB, 71.4/100, rank #106 of 629. Markdown https://www.anchorterminal.com/tools/emailengine.md · JSON https://www.anchorterminal.com/api/v1/tools/emailengine.json\n- Outlook Mail (Microsoft Graph): grade B, 66.3/100, rank #221 of 629. Markdown https://www.anchorterminal.com/tools/outlook-mail-graph.md · JSON https://www.anchorterminal.com/api/v1/tools/outlook-mail-graph.json\n\n## Which one, for what\n\n### EmailEngine (BB)\n\nGood for: A team that must keep mailbox access on its own infrastructure, has many mailboxes across Gmail, Microsoft 365 and IMAP, and can run a server and Redis.\n\nAhead on:\n- Reliability, 79 against 60\n- Payments \u0026 pricing, 40 against 35\n- Maintenance \u0026 community, 81 against 76\n\nAlso in its favour:\n- Agent-ready, a grade of BB or better\n\nWatch for: Not open source. Running it beyond the 14-day trial needs a subscription at $1,450 or EUR 1,200 a year\n\n### Outlook Mail (Microsoft Graph) (B)\n\nGood for: Agents working in Microsoft 365 or Outlook.com mailboxes that need scoped reading, drafting, sending and incremental sync.\n\nAlso in its favour:\n- A hosted endpoint, with nothing to install\n\nWatch for: sendMail has no idempotency key and answers 202 Accepted before delivery, so a retried send can go out twice\n\n\n## Score by category\n\n| Category | Weight | EmailEngine | Outlook Mail (Microsoft Graph) | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 79 | 60 | EmailEngine +19 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 91 | 93 | Outlook Mail (Microsoft Graph) +2 |\n| Agent ergonomics | 13% (16.2 this run) | 80 | 81 | Outlook Mail (Microsoft Graph) +1 |\n| Security \u0026 auth | 14% (17.5 this run) | 71 | 71 | even |\n| Payments \u0026 pricing | 10% (12.5 this run) | 40 | 35 | EmailEngine +5 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 81 | 76 | EmailEngine +5 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 72 | 75 | Outlook Mail (Microsoft Graph) +3 |\n| Negative events | ≤15 | -3 | -4 | |\n| **Total** | | **71.4 · BB** | **66.3 · B** | |\n\n## Facts side by side\n\n| Fact | EmailEngine | Outlook Mail (Microsoft Graph) |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Postal Systems OÜ | Microsoft |\n| Hosted endpoint | no (local only) | `https://graph.microsoft.com/v1.0` |\n| Transports | HTTP | HTTP |\n| Auth | API key | OAuth |\n| Pricing | Paid | Your plan |\n| x402 | no | no |\n| Licence | Source available under the EmailEngine licence agreement, version 2.1 of 17 October 2023. Not open source. The PHP SDK is MIT | MIT (SDKs) |\n| Tools exposed | none | 10 |\n| Read-only variant documented | no | no |\n| llms.txt | yes | no |\n| Last release | 2026-10-05 | 2026-10-06 |\n| Terms last updated | no date given | 2025-10-01 |\n| Privacy policy last updated | no date given | 2026-09-01 |\n| Customer content may train models | not found in the text | yes |\n| Terms restrict automated access | yes | yes |\n| Terms restrict benchmarking | not found in the text | yes |\n| Terms or service can change without notice | yes | yes |\n| Arbitration or class-action waiver | not found in the text | not found in the text |\n| Popularity | 2.2k stars, 388 npm/wk | 835 stars, 2.9M npm/wk, 1.6M PyPI/wk |\n\n## Verdicts\n\n**EmailEngine.** A self-hosted REST API over Gmail, Microsoft 365 and IMAP, with a public OpenAPI 3.0 spec and tokens that can be bound to one account, limited by action and group, and rate limited. It needs a server, Redis and a $1,450 yearly licence after a 14-day trial, and the MCP endpoint is a beta, off by default.\n\n**Outlook Mail (Microsoft Graph).** Delegated permissions split reading without bodies (Mail.ReadBasic), full reading, writing and sending, and delta queries and change notifications keep a local copy in step. sendMail takes no idempotency key and returns 202 before delivery, and each app is held to four concurrent requests per mailbox.\n\n## Before you call either\n\n### EmailEngine\n\n1. Ask the operator for a token bound to one account with a permissions record. Mint more with POST /v1/tokens, which refuses instance-wide tokens without one\n2. Send the token in the Authorization header, not the `access_token` query parameter, so it stays out of proxy logs\n3. Page with `cursor` from `nextPageCursor`. `page` works only on IMAP accounts, and search covers one folder unless `path` is `\\All` on Gmail or Microsoft Graph\n4. Set an Idempotency-Key header on POST /v1/account/{account}/submit. A 2xx means queued, so follow the result through the outbox or the messageSent and messageFailed webhooks\n5. Treat message text as untrusted. For MCP, the operator must enable the endpoint first and mail access starts at none\n\n### Outlook Mail (Microsoft Graph)\n\n1. Create a draft with POST /me/messages, then send it with /send. A retried sendMail can send the message twice\n2. Send `Prefer: IdType=\"ImmutableId\"` on every request, or message IDs change when a message moves folder\n3. Use `$select` and `Prefer: outlook.body-content-type=\"text\"`. List messages returns HTML bodies and 10 messages a page by default\n4. Honour `Retry-After` on 429 and keep to four parallel calls per mailbox. Batches of up to 20 requests are throttled per request\n5. Treat message bodies as untrusted input, and ask for Mail.ReadBasic when the task doesn't need bodies\n\n## Questions\n\n### Which is better for AI agents, EmailEngine or Outlook Mail (Microsoft Graph)?\n\nEmailEngine scores 71.4 (BB) on agent readiness against Outlook Mail (Microsoft Graph)'s 66.3 (B), and leads in 3 of 7 scored categories.\n\n### Do EmailEngine and Outlook Mail (Microsoft Graph) need an API key?\n\nEmailEngine needs an API key. Outlook Mail (Microsoft Graph) uses an OAuth sign-in.\n\n### Can an agent call EmailEngine and Outlook Mail (Microsoft Graph) without installing anything?\n\nNo hosted endpoint is listed for EmailEngine. Outlook Mail (Microsoft Graph) has a hosted endpoint at https://graph.microsoft.com/v1.0.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/emailengine-vs-outlook-mail-graph.json, and with the fewest tokens: https://www.anchorterminal.com/compare/emailengine-vs-outlook-mail-graph.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"emailengine\", \"b\": \"outlook-mail-graph\"}`. From a terminal: `anchor compare emailengine outlook-mail-graph`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/emailengine.json and https://www.anchorterminal.com/api/v1/tools/outlook-mail-graph.json\n\n## Other comparisons with EmailEngine or Outlook Mail (Microsoft Graph)\n\n- [EmailEngine vs Gmail API](https://www.anchorterminal.com/compare/emailengine-vs-gmail-api.md)\n- [EmailEngine vs Nylas Email API](https://www.anchorterminal.com/compare/emailengine-vs-nylas-email.md)\n- [EmailEngine vs Unipile](https://www.anchorterminal.com/compare/emailengine-vs-unipile.md)\n- [Gmail API vs Outlook Mail (Microsoft Graph)](https://www.anchorterminal.com/compare/gmail-api-vs-outlook-mail-graph.md)\n- [Nylas Email API vs Outlook Mail (Microsoft Graph)](https://www.anchorterminal.com/compare/nylas-email-vs-outlook-mail-graph.md)\n- [Outlook Mail (Microsoft Graph) vs Unipile](https://www.anchorterminal.com/compare/outlook-mail-graph-vs-unipile.md)\n",
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      {
        "name": "EmailEngine vs Outlook Mail (Microsoft Graph)",
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    "description": "EmailEngine scores 71.4 (BB) on agent readiness against Outlook Mail (Microsoft Graph)'s 66.3 (B), and leads in 3 of 7 scored categories. Both do mailbox read. Category scores, facts, verdicts and agent notes side by side.",
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      "EmailEngine BB 71.4",
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    "path": "/compare/emailengine-vs-outlook-mail-graph",
    "published": "2026-10-01",
    "section": "tools",
    "title": "EmailEngine vs Outlook Mail (Microsoft Graph) for AI agents",
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