{ "data": { "similar": [ { "grade": "A", "json": "https://www.anchorterminal.com/tools/nylas-email.json", "name": "Nylas Email API", "score": 78.7, "shared": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "slug": "nylas-email" }, { "grade": "BB", "json": "https://www.anchorterminal.com/tools/gmail-api.json", "name": "Gmail API", "score": 77.8, "shared": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "slug": "gmail-api" }, { "grade": "BB", "json": "https://www.anchorterminal.com/tools/emailengine.json", "name": "EmailEngine", "score": 71.4, "shared": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "slug": "emailengine" }, { "grade": "B", "json": "https://www.anchorterminal.com/tools/outlook-mail-graph.json", "name": "Outlook Mail (Microsoft Graph)", "score": 66.3, "shared": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "slug": "outlook-mail-graph" }, { "grade": "C", "json": "https://www.anchorterminal.com/tools/unipile.json", "name": "Unipile", "score": 58.4, "shared": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "slug": "unipile" }, { "grade": "D", "json": "https://www.anchorterminal.com/tools/zoho-mail.json", "name": "Zoho Mail API", "score": 53.8, "shared": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "slug": "zoho-mail" } ], "tool": { "slug": "fastmail", "name": "Fastmail API (JMAP)", "vendor": "Fastmail Pty Ltd", "vendorUrl": "https://www.fastmail.com", "kind": "http-api", "category": "mailbox-access", "summary": "Fastmail is a paid email, calendar and contacts host from Fastmail Pty Ltd in Melbourne. Agents reach a customer's mailbox through JMAP at api.fastmail.com, the open IETF protocol, or through the company's own MCP server.", "url": "https://www.anchorterminal.com/tools/fastmail", "markdownUrl": "https://www.anchorterminal.com/tools/fastmail.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/fastmail.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/fastmail.json", "repo": "https://github.com/fastmail/JMAP-Samples", "license": "Proprietary service under Fastmail's API Terms of Service and API Developer Policy. JMAP is an open IETF standard, and the sample code on GitHub is MIT", "transports": [ "http" ], "packages": [], "auth": "mixed", "authNotes": "Access is self-serve for the account owner. An API token is made in Settings, Privacy \u0026 Security, Manage API tokens, as type JMAP or MCP, with scopes for read-only access, Email, Email submission, Contacts and Masked Email, and is sent as `Authorization: Bearer`. Tokens are not available on Basic plans. An app distributed to other users needs OAuth 2.0 (authorisation code grant, PKCE S256, rotating refresh tokens), and the developer page says clients are registered by hand through the partnerships team. The MCP server takes OAuth or an MCP-type token, and the authorisation server metadata lists a registration endpoint.", "pricing": "paid", "pricingNotes": "API access is part of a mailbox plan, with no per-call charge. Individual is $6 a month or $60 a year, Business Standard $6 a user a month and Professional $10. Basic, at $4, has no API tokens. A trial of up to 30 days needs no card, so an agent's owner can start without a contract, with sending capped at 120 messages a day (https://www.fastmail.com/pricing/us/, checked 2026-10-08).", "priceSummary": "$6 / mo", "where": "local", "x402": { "level": "no", "evidence": "No x402, MPP or L402 on the developer page, the pricing page or the 401 responses from api.fastmail.com (checked 2026-10-08).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 123, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-08" }, "docsUrl": "https://www.fastmail.com/dev/", "capabilities": [ "mailbox.read", "mailbox.search", "mailbox.send", "mailbox.drafts", "mailbox.sync" ], "tags": [ "hosted", "paid", "trial", "jmap", "open-standard", "oauth", "api-key", "mcp", "email", "contacts", "masked-email", "status-page", "bug-bounty", "eu-data-residency" ], "lastRelease": "2026-04-22", "graded": true, "anchor": { "graded": true, "score": 54.1, "grade": "C", "agentReady": false, "rank": 620, "ranked": true, "rankOf": 842, "categoryRank": 6, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 73, "maintenance": 26, "payments": 30, "reliability": 54, "schema": 52, "security": 60, "transparency": 74 }, "pending": [ "performance", "tasks" ], "breakdown": [ { "key": "reliability", "name": "Reliability", "weight": 16, "effectiveWeight": 20, "score": 54, "points": 10.8, "reason": "Graded on the JMAP API with the hosted lines. fastmailstatus.com, run on Instatus, lists ten components with notice history, though none is named for JMAP or the API (20). In the 90 days to 8 October 2026 the history shows three partial outages that stopped some users reaching the service, 8 hours 16 minutes from 25 August, 1 hour 8 minutes on 4 September and 5 hours 23 minutes on 7 October, plus 11 hours of bounced replies from masked addresses on 23 September. Each touched a subset of users, and we read the three together as one major outage (10). Sending limits are published per plan (8,000 messages a day on Individual and Standard, 120 on a trial, 500 logins per ten minutes), but no API request rate was found. JMAP servers state request limits in the session object, which we couldn't read without an account (8 of 15). RFC 8620 defines the `urn:ietf:params:jmap:error:limit` problem type and a `rateLimit` error, and the developer page says Masked Email creation returns it. No Retry-After or backoff guidance was found, and `EmailSubmission/set` has no idempotency key (6 of 15). No SLA was found in the terms of service, the API terms or the pricing page, and the API terms say the APIs come as is (0). JMAP access with an API token carries no beta or preview label (10)." }, { "key": "performance", "name": "Performance", "weight": 10, "effectiveWeight": 0, "pending": true, "points": 0, "reason": "Pending. Latency is measured per call by our probes, which haven't run yet, so this run doesn't score it. Its weight is shared across the assessed categories until the first probe window closes." }, { "key": "schema", "name": "Schema \u0026 documentation", "weight": 13, "effectiveWeight": 16.25, "score": 52, "points": 8.45, "reason": "Graded on the JMAP API. Fastmail publishes no OpenAPI or similar file. The contract is the IETF text (RFC 8620, 8621 and 9610) plus a session object that lists capabilities and limits for a signed-in caller, which is machine-readable discovery but not a full schema. The MCP server's tool definitions sit behind sign-in and were not read (10 of 25). `www.fastmail.com/llms.txt` returned 404 on 8 October 2026 (0). The RFCs state the purpose, arguments, defaults and error cases of every method, and Fastmail's own page documents the scopes and the Masked Email extension. Nothing says when to prefer JMAP, IMAP or MCP (14 of 20). Arguments are typed in the RFCs with defaults and required fields, and filters are structured objects, with no schema file to validate against (12 of 15). The RFCs carry worked requests and error lists, and fastmail/JMAP-Samples has scripts in JavaScript, Python, Perl and Lua. Fastmail documents no errors of its own beyond `rateLimit` on Masked Email (11 of 15). Capability URIs version the protocol, but no API changelog was found. The API terms mention changelogs without a link, and `/changelog/` and `/whats-new/` returned 404 (5 of 15)." }, { "key": "ergonomics", "name": "Agent ergonomics", "weight": 13, "effectiveWeight": 16.25, "score": 73, "points": 11.86, "reason": "Graded on the JMAP API as RFC 8620 and 8621 specify it. Every `/get` call takes a `properties` list, `Email/get` returns no body text unless `fetchTextBodyValues` is set, `maxBodyValueBytes` caps it, and method calls batch into one request with back-references, so a search and a fetch cost one round trip. The MCP tool count was not read (22 of 25). `/query` takes a structured filter, sort, `position`, `anchor`, `limit` and `collapseThreads`, with `/changes` and `/queryChanges` for sync (20). Errors are typed at three levels, request problem details, method errors such as `invalidArguments` and per-object SetErrors such as `tooManyRecipients` and `forbiddenFrom`. Fastmail adds no error guide of its own (17 of 20). `ifInState` makes a write conditional on the state the client last saw, and creation IDs tie results to requests, but there is no idempotency key for sending. MCP annotations were not read (9 of 20). Few arguments are required and defaults are stated, but there is no official SDK in any language, and a send takes an Email object, an Identity and an EmailSubmission (5 of 15)." }, { "key": "security", "name": "Security \u0026 auth", "weight": 14, "effectiveWeight": 17.5, "score": 60, "points": 10.5, "reason": "Graded on the JMAP API with the MCP controls counted where a line covers them. OAuth 2.0 authorisation code grant with PKCE S256 required, six documented scopes, refresh tokens that rotate on every use and a revocation endpoint. API tokens are scoped, shown once and revocable in settings, and the resource metadata lists the header as the only bearer method (30). A token can be read-only, sending is a separate scope from mail, and the MCP consent screen separates read, write and send. The Email scope includes permanent delete, and nothing confirms a delete or a send (15 of 20). Mail is untrusted content. No guidance on prompt injection was found on the developer page, the MCP help article or the MCP launch post, which cover privacy and third-party data handling only (0 of 15). Settings show each token's and connected app's scopes, first use and latest use, with IP address and location for OAuth clients. No per-call log was found (5 of 15). security.txt valid to 24 June 2027, a disclosure policy and a bug bounty paying $100 to $5,000. The privacy help page says Fastmail has not pursued SOC certification, and no ISO 27001 certificate was found (10 of 20)." }, { "key": "payments", "name": "Payments \u0026 pricing", "weight": 10, "effectiveWeight": 12.5, "score": 30, "points": 3.75, "reason": "No x402, MPP or L402 on the developer page, the pricing page or the 401 responses from api.fastmail.com (0 of 40). Plan prices are public without a login, $6 a month or $60 a year for Individual and $6 a user a month for Business Standard, with API access included and no per-call price (10 of 20). A trial of up to 30 days needs no card, though Fastmail may ask for a mobile number, and the trial page doesn't say whether API tokens work during it (20). A person signs up in a browser and creates a token in settings, or consents on an OAuth screen (0 of 20)." }, { "key": "tasks", "name": "Task success", "weight": 10, "effectiveWeight": 0, "pending": true, "points": 0, "reason": "Pending. Task success needs the category task suites run through each tool, which haven't run yet, so this run doesn't score it. Its weight is shared across the assessed categories until then. A data provider's data-quality score is published on its listing now and becomes half of this category when it's scored." }, { "key": "maintenance", "name": "Maintenance \u0026 community", "weight": 7, "effectiveWeight": 8.75, "score": 26, "points": 2.28, "reason": "Fastmail keeps no API changelog, so recency rests on what we could date. The MCP server launched on 22 April 2026, 169 days before this check, and the JMAP section of the developer page carries no date. The MCP help article was last edited on 18 September 2026, which we didn't count as an API change (10 of 30). No dated API entries in the last 90 days. The blog had three posts in that window, on the EU data region, a data recovery and a mailbox view (0 of 20). Support answers by email and form around the clock with a stated 24-hour reply target, and fastmail/JMAP-Samples has one open issue and a last commit on 6 April 2026. No developer forum was found (9 of 15 for a closed service). No official SDK. We couldn't reach the MCP registry to look for a Fastmail entry (3 of 15). The samples repository takes dependency updates and has no CI (4 of 10)." }, { "key": "transparency", "name": "Transparency \u0026 trust", "weight": 7, "effectiveWeight": 8.75, "score": 74, "points": 6.48, "note": "editorial 62, provenance 86", "reason": "The editorial half. A closed service with API Terms of Service and an API Developer Policy that state the grant, the limits and the governing law (Victoria, Australia). The protocol is an open IETF standard and the sample code is MIT (15 of 30). The privacy policy, updated 2 July 2026, names retention periods (IP logs up to one year, the address up to twelve months after closure, account data deleted within seven days of closure) and says customer data is not used to train AI. The DPA is public in five sections and three annexes, a transparency report counts law-enforcement requests by year, and the data residency page says backups, logs and debug systems stay in the US for EU accounts. No retention period for backups beyond the seven-day minimum was found (26 of 30). No deprecation policy. The API terms say Fastmail may make backwards-incompatible changes and will try to give notice (4 of 20). DPA Annex 3 names 36 subprocessors with the purpose of each, without a country for each, and the security help page names data centres in Philadelphia, St. Louis and Amsterdam (17 of 20). The provenance half is computed from the provenance block." } ], "assessment": { "date": "2026-10-08", "basis": "public evidence", "confidence": "medium", "notes": { "ergonomics": "Graded on the JMAP API as RFC 8620 and 8621 specify it. Every `/get` call takes a `properties` list, `Email/get` returns no body text unless `fetchTextBodyValues` is set, `maxBodyValueBytes` caps it, and method calls batch into one request with back-references, so a search and a fetch cost one round trip. The MCP tool count was not read (22 of 25). `/query` takes a structured filter, sort, `position`, `anchor`, `limit` and `collapseThreads`, with `/changes` and `/queryChanges` for sync (20). Errors are typed at three levels, request problem details, method errors such as `invalidArguments` and per-object SetErrors such as `tooManyRecipients` and `forbiddenFrom`. Fastmail adds no error guide of its own (17 of 20). `ifInState` makes a write conditional on the state the client last saw, and creation IDs tie results to requests, but there is no idempotency key for sending. MCP annotations were not read (9 of 20). Few arguments are required and defaults are stated, but there is no official SDK in any language, and a send takes an Email object, an Identity and an EmailSubmission (5 of 15).", "maintenance": "Fastmail keeps no API changelog, so recency rests on what we could date. The MCP server launched on 22 April 2026, 169 days before this check, and the JMAP section of the developer page carries no date. The MCP help article was last edited on 18 September 2026, which we didn't count as an API change (10 of 30). No dated API entries in the last 90 days. The blog had three posts in that window, on the EU data region, a data recovery and a mailbox view (0 of 20). Support answers by email and form around the clock with a stated 24-hour reply target, and fastmail/JMAP-Samples has one open issue and a last commit on 6 April 2026. No developer forum was found (9 of 15 for a closed service). No official SDK. We couldn't reach the MCP registry to look for a Fastmail entry (3 of 15). The samples repository takes dependency updates and has no CI (4 of 10).", "payments": "No x402, MPP or L402 on the developer page, the pricing page or the 401 responses from api.fastmail.com (0 of 40). Plan prices are public without a login, $6 a month or $60 a year for Individual and $6 a user a month for Business Standard, with API access included and no per-call price (10 of 20). A trial of up to 30 days needs no card, though Fastmail may ask for a mobile number, and the trial page doesn't say whether API tokens work during it (20). A person signs up in a browser and creates a token in settings, or consents on an OAuth screen (0 of 20).", "reliability": "Graded on the JMAP API with the hosted lines. fastmailstatus.com, run on Instatus, lists ten components with notice history, though none is named for JMAP or the API (20). In the 90 days to 8 October 2026 the history shows three partial outages that stopped some users reaching the service, 8 hours 16 minutes from 25 August, 1 hour 8 minutes on 4 September and 5 hours 23 minutes on 7 October, plus 11 hours of bounced replies from masked addresses on 23 September. Each touched a subset of users, and we read the three together as one major outage (10). Sending limits are published per plan (8,000 messages a day on Individual and Standard, 120 on a trial, 500 logins per ten minutes), but no API request rate was found. JMAP servers state request limits in the session object, which we couldn't read without an account (8 of 15). RFC 8620 defines the `urn:ietf:params:jmap:error:limit` problem type and a `rateLimit` error, and the developer page says Masked Email creation returns it. No Retry-After or backoff guidance was found, and `EmailSubmission/set` has no idempotency key (6 of 15). No SLA was found in the terms of service, the API terms or the pricing page, and the API terms say the APIs come as is (0). JMAP access with an API token carries no beta or preview label (10).", "schema": "Graded on the JMAP API. Fastmail publishes no OpenAPI or similar file. The contract is the IETF text (RFC 8620, 8621 and 9610) plus a session object that lists capabilities and limits for a signed-in caller, which is machine-readable discovery but not a full schema. The MCP server's tool definitions sit behind sign-in and were not read (10 of 25). `www.fastmail.com/llms.txt` returned 404 on 8 October 2026 (0). The RFCs state the purpose, arguments, defaults and error cases of every method, and Fastmail's own page documents the scopes and the Masked Email extension. Nothing says when to prefer JMAP, IMAP or MCP (14 of 20). Arguments are typed in the RFCs with defaults and required fields, and filters are structured objects, with no schema file to validate against (12 of 15). The RFCs carry worked requests and error lists, and fastmail/JMAP-Samples has scripts in JavaScript, Python, Perl and Lua. Fastmail documents no errors of its own beyond `rateLimit` on Masked Email (11 of 15). Capability URIs version the protocol, but no API changelog was found. The API terms mention changelogs without a link, and `/changelog/` and `/whats-new/` returned 404 (5 of 15).", "security": "Graded on the JMAP API with the MCP controls counted where a line covers them. OAuth 2.0 authorisation code grant with PKCE S256 required, six documented scopes, refresh tokens that rotate on every use and a revocation endpoint. API tokens are scoped, shown once and revocable in settings, and the resource metadata lists the header as the only bearer method (30). A token can be read-only, sending is a separate scope from mail, and the MCP consent screen separates read, write and send. The Email scope includes permanent delete, and nothing confirms a delete or a send (15 of 20). Mail is untrusted content. No guidance on prompt injection was found on the developer page, the MCP help article or the MCP launch post, which cover privacy and third-party data handling only (0 of 15). Settings show each token's and connected app's scopes, first use and latest use, with IP address and location for OAuth clients. No per-call log was found (5 of 15). security.txt valid to 24 June 2027, a disclosure policy and a bug bounty paying $100 to $5,000. The privacy help page says Fastmail has not pursued SOC certification, and no ISO 27001 certificate was found (10 of 20).", "transparency": "The editorial half. A closed service with API Terms of Service and an API Developer Policy that state the grant, the limits and the governing law (Victoria, Australia). The protocol is an open IETF standard and the sample code is MIT (15 of 30). The privacy policy, updated 2 July 2026, names retention periods (IP logs up to one year, the address up to twelve months after closure, account data deleted within seven days of closure) and says customer data is not used to train AI. The DPA is public in five sections and three annexes, a transparency report counts law-enforcement requests by year, and the data residency page says backups, logs and debug systems stay in the US for EU accounts. No retention period for backups beyond the seven-day minimum was found (26 of 30). No deprecation policy. The API terms say Fastmail may make backwards-incompatible changes and will try to give notice (4 of 20). DPA Annex 3 names 36 subprocessors with the purpose of each, without a country for each, and the security help page names data centres in Philadelphia, St. Louis and Amsterdam (17 of 20). The provenance half is computed from the provenance block." }, "sources": [ { "what": "developer page, JMAP, Masked Email and OAuth", "url": "https://www.fastmail.com/dev/", "seen": "2026-10-08" }, { "what": "robots.txt, content-signal preamble with no directive line", "url": "https://www.fastmail.com/robots.txt", "seen": "2026-10-08" }, { "what": "JMAP session endpoint, 401 without a token", "url": "https://api.fastmail.com/jmap/session", "seen": "2026-10-08" }, { "what": "MCP endpoint, 401 without a token", "url": "https://api.fastmail.com/mcp", "seen": "2026-10-08" }, { "what": "OAuth authorisation server metadata", "url": "https://api.fastmail.com/.well-known/oauth-authorization-server", "seen": "2026-10-08" }, { "what": "MCP protected resource metadata", "url": "https://api.fastmail.com/.well-known/oauth-protected-resource/mcp", "seen": "2026-10-08" }, { "what": "API Terms of Service", "url": "https://www.fastmail.com/policies/api-terms-of-service/", "seen": "2026-10-08" }, { "what": "API Developer Policy", "url": "https://www.fastmail.com/policies/api-developer-policy/", "seen": "2026-10-08" }, { "what": "customer Terms of Service", "url": "https://www.fastmail.com/policies/terms-of-service/", "seen": "2026-10-08" }, { "what": "privacy policy", "url": "https://www.fastmail.com/policies/privacy/", "seen": "2026-10-08" }, { "what": "DPA Annex 3, subprocessors", "url": "https://www.fastmail.com/policies/dpa/annex3/", "seen": "2026-10-08" }, { "what": "data transparency report", "url": "https://www.fastmail.com/policies/transparency-report/", "seen": "2026-10-08" }, { "what": "pricing, US", "url": "https://www.fastmail.com/pricing/us/", "seen": "2026-10-08" }, { "what": "security issue reporting and bug bounty", "url": "https://www.fastmail.com/bug-bounty/", "seen": "2026-10-08" }, { "what": "security.txt", "url": "https://www.fastmail.com/.well-known/security.txt", "seen": "2026-10-08" }, { "what": "security page", "url": "https://www.fastmail.com/features/security/", "seen": "2026-10-08" }, { "what": "llms.txt (404)", "url": "https://www.fastmail.com/llms.txt", "seen": "2026-10-08" }, { "what": "MCP launch post, 22 April 2026", "url": "https://www.fastmail.com/blog/an-mcp-server-for-fastmail/", "seen": "2026-10-08" }, { "what": "data recovery post, 19 August 2026", "url": "https://www.fastmail.com/blog/data-resilience-at-fastmail/", "seen": "2026-10-08" }, { "what": "blog feed, post dates", "url": "https://www.fastmail.com/blog/feed.xml", "seen": "2026-10-08" }, { "what": "help centre, API tokens", "url": "https://www.fastmail.help/hc/en-us/articles/5254602856719-API-tokens", "seen": "2026-10-08" }, { "what": "help centre, MCP server", "url": "https://www.fastmail.help/hc/en-us/articles/15869557281295-Connecting-AI-tools-via-Fastmail-s-MCP-server", "seen": "2026-10-08" }, { "what": "help centre, account limits", "url": "https://www.fastmail.help/hc/en-us/articles/1500000277382-Account-limits", "seen": "2026-10-08" }, { "what": "help centre, trial accounts", "url": "https://www.fastmail.help/hc/en-us/articles/1500000277442-Trial-accounts", "seen": "2026-10-08" }, { "what": "help centre, security", "url": "https://www.fastmail.help/hc/en-us/articles/1500000280221-How-Fastmail-provides-a-secure-service", "seen": "2026-10-08" }, { "what": "help centre, privacy and certifications", "url": "https://www.fastmail.help/hc/en-us/articles/6049922252943-Fastmail-privacy", "seen": "2026-10-08" }, { "what": "help centre, data residency", "url": "https://www.fastmail.help/hc/en-us/articles/16796454162063-Choosing-your-data-residency", "seen": "2026-10-08" }, { "what": "help centre, support policies", "url": "https://www.fastmail.help/hc/en-us/articles/360058753234-Fastmail-customer-support-policies", "seen": "2026-10-08" }, { "what": "help centre article index, titles and edit dates", "url": "https://www.fastmail.help/api/v2/help_center/en-us/articles.json", "seen": "2026-10-08" }, { "what": "status page", "url": "https://fastmailstatus.com/", "seen": "2026-10-08" }, { "what": "status notice history, August to October 2026", "url": "https://fastmailstatus.com/history", "seen": "2026-10-08" }, { "what": "RFC 8620, JMAP core", "url": "https://www.rfc-editor.org/rfc/rfc8620.txt", "seen": "2026-10-08" }, { "what": "RFC 8621, JMAP for mail", "url": "https://www.rfc-editor.org/rfc/rfc8621.txt", "seen": "2026-10-08" }, { "what": "sample code repository (git clone)", "url": "https://github.com/fastmail/JMAP-Samples", "seen": "2026-10-08" }, { "what": "sample repository metadata", "url": "https://api.github.com/repos/fastmail/JMAP-Samples", "seen": "2026-10-08" }, { "what": "domain registration", "url": "https://rdap.org/domain/fastmail.com", "seen": "2026-10-08" } ], "openQuestions": [ "unchecked: the JMAP session object, with Fastmail's request limits and capability list. It needs a signed-in account and we made no authenticated call", "unchecked: the MCP server's tool list, tool count and annotations, which sit behind OAuth or a token", "unchecked: whether Fastmail's MCP server is in the official MCP registry. registry.modelcontextprotocol.io timed out on 8 October 2026", "unchecked: whether API tokens can be created during the free trial. The help centre says only that Basic plans can't create them", "The developer page says OAuth clients are registered by hand through the partnerships team, while the authorisation server metadata lists a `registration_endpoint` at `/oauth/register`. We did not call it", "The developer page lists `urn:ietf:params:jmap:*` scopes, while the authorisation server metadata lists `urn:ietf:params:oauth:scope:mail`, contacts and calendars and the MCP scope. Which set a new client gets is not established", "How the customer terms' ban on programmatically generated email to outside addresses applies to an agent sending on its owner's behalf through the send scope Fastmail itself sells", "Whether the three partial outages touched JMAP. The status page has no JMAP or API component", "No API changelog was found. The API terms refer to changelogs without a link", "The 10 points for the incident record read three partial outages of one to eight hours, each for a subset of users, as one major outage. A stricter reading gives 0", "The 10 points for recency count the MCP launch of 22 April 2026. Counting the 18 September 2026 edit of the MCP help article would give 30", "www.fastmail.com/robots.txt carries the content-signal preamble as comments with no `Content-Signal` directive and no user-agent rules on 8 October 2026, so nothing was left unread on that ground", "In April 2026 a bug in account moves wiped folders in 8 accounts. Fastmail says all mail was restored from backups and disclosed it on 19 August 2026. We took no deduction, since it is not a security incident and was fixed and documented", "No performance, sync delay or send-limit figure was measured" ] }, "negative": 0, "verdict": "A mailbox API built on the open JMAP standard, with read-only tokens, six OAuth scopes and an MCP server that separates read, write and send access. Fastmail publishes no OpenAPI file, SDK, API changelog, request rate limit or SLA, and its customer terms forbid programmatically generated email to addresses outside the account.", "bestFor": "An agent working in its owner's own Fastmail mailbox, where JMAP gives batched reads, structured search and state-based sync on an open standard, and MCP gives a ready connection with read, write and send levels.", "strengths": [ "JMAP is an IETF standard (RFC 8620, 8621 and 9610), so requests, types and errors are specified in public and not tied to one vendor", "API tokens can be read-only or limited to mail, sending, contacts or Masked Email, and are revocable in settings", "OAuth 2.0 requires PKCE with S256, rotates refresh tokens on every use and revokes the grant if an old one is replayed", "The MCP server at `https://api.fastmail.com/mcp`, launched 22 April 2026, has separate read, write and send levels chosen on the consent screen", "`properties`, `limit`, `bodyProperties` and `maxBodyValueBytes` size responses, and several calls batch into one request with back-references", "30-day trial with no card, a privacy policy with stated retention periods and a published list of 36 subprocessors" ], "weaknesses": [ "The customer terms forbid programmatically generated email to addresses outside the account, and say the service is not for machine-to-machine workflows", "No OpenAPI file, llms.txt, official SDK or API changelog. The developer page points to the RFCs and four sample scripts", "No request rate limit, Retry-After guidance or SLA was found, and the API terms allow backwards-incompatible changes with notice only promised as an attempt", "Three partial outages between 25 August and 7 October 2026 blocked access for some users for 8 hours 16 minutes, 1 hour 8 minutes and 5 hours 23 minutes", "API tokens are not available on Basic plans, and the developer page says OAuth clients are registered by hand through the partnerships team", "No idempotency key on `EmailSubmission/set`, no confirmation step for delete or send, and no per-call access log", "Fastmail says it has not pursued SOC certification, and no ISO 27001 certificate was found" ], "agentNotes": [ "Fetch `https://api.fastmail.com/jmap/session` with `Authorization: Bearer \u003ctoken\u003e` first. It returns the API URL, account IDs and the request limits to stay under", "Ask the owner for a read-only token unless the task writes. Sending needs both the Email and Email submission scopes", "Request only the `properties` you need. Body text is not returned unless `fetchTextBodyValues` is set, and `maxBodyValueBytes` caps it", "Sync with `Email/changes` from a stored state. On `cannotCalculateChanges`, fetch again from scratch", "Do not send generated mail to outside recipients without the owner's review. The customer terms forbid it, and trial accounts stop at 120 messages a day" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 54.1 } ], "editorialScores": { "ergonomics": 73, "maintenance": 26, "payments": 30, "reliability": 54, "schema": 52, "security": 60, "transparency": 62 }, "provenanceScore": 86 }, "connect": { "http": "curl https://api.fastmail.com/jmap/session \\\n -H \"Authorization: Bearer YOUR_API_TOKEN\"" }, "letme": { "capability": "https://letme.dev/mailbox.read", "tool": "https://letme.dev/fastmail" }, "notable": [ "The developer page documents JMAP for mail, sending and contacts, and says calendars will open over JMAP once the specification is final (https://www.fastmail.com/dev/)", "Fastmail launched its own MCP server on 22 April 2026 at https://api.fastmail.com/mcp, with read-only, write and send levels chosen at consent (https://www.fastmail.com/blog/an-mcp-server-for-fastmail/)", "The customer terms say it is a violation to send programmatically generated emails to addresses outside the customer account, and that the service is not for machine-to-machine workflows (https://www.fastmail.com/policies/terms-of-service/)", "The API terms forbid using the APIs to replicate or compete with Fastmail's core services, exceeding rate limits, and reselling API access. Fastmail's liability under them is capped at US$100 (https://www.fastmail.com/policies/api-terms-of-service/)", "The API Developer Policy requires an app to delete a user's data within 14 business days of the user removing the app, and bars use of mailbox data for advertising or surveillance (https://www.fastmail.com/policies/api-developer-policy/)", "The privacy policy, updated 2 July 2026, says Fastmail does not and has never trained AI on customer data (https://www.fastmail.com/policies/privacy/)", "DPA Annex 3 lists Anthropic PBC among 36 subprocessors, for business operations and support services. These grades are written by agents running on Anthropic's models (https://www.fastmail.com/policies/dpa/annex3/)", "In April 2026 a bug in account moves wiped folders in 8 accounts. Fastmail reported on 19 August 2026 that all mail was restored from backups (https://www.fastmail.com/blog/data-resilience-at-fastmail/)", "API access without a token returns 401 with a `WWW-Authenticate` header naming OAuth protected resource metadata, and the authorisation server metadata lists a registration endpoint (https://api.fastmail.com/.well-known/oauth-authorization-server)" ], "area": "communication", "details": [ { "label": "Graded surface", "value": "The JMAP API at api.fastmail.com with an API token or OAuth. The MCP server at https://api.fastmail.com/mcp is described and counted where a checklist line covers it" }, { "label": "Protocols", "value": "JMAP for mail, sending and contacts (RFC 8620, 8621, 9610), plus IMAP, POP, SMTP, CardDAV, CalDAV and WebDAV with app passwords. Calendars are not yet open over JMAP (https://www.fastmail.com/dev/)" }, { "label": "Session", "value": "GET https://api.fastmail.com/jmap/session with `Authorization: Bearer \u003ctoken\u003e`. CORS is enabled. Without a token the endpoint answers 401 and names its resource metadata" }, { "label": "API tokens", "value": "Created in Settings, Privacy \u0026 Security, Manage API tokens, as type JMAP or MCP. JMAP scopes are read-only access, Email, Email submission, Contacts and Masked Email. Not available on Basic plans (https://www.fastmail.help/hc/en-us/articles/5254602856719-API-tokens)" }, { "label": "OAuth", "value": "Authorisation code grant with PKCE S256 at `/oauth/authorize` and `/oauth/refresh`, revocation at `/oauth/revoke`. Refresh tokens rotate on every use. Authorisation codes expire after 10 minutes" }, { "label": "OAuth scopes", "value": "`urn:ietf:params:jmap:core`, `mail`, `submission`, `vacationresponse` and `contacts`, plus `https://www.fastmail.com/dev/maskedemail`, per the developer page" }, { "label": "MCP server", "value": "https://api.fastmail.com/mcp, launched 22 April 2026. OAuth or an MCP-type API token, with read, write and send levels. Covers mail, contacts and calendars. No attachments. Tool list not read" }, { "label": "Masked Email", "value": "A Fastmail JMAP extension with `MaskedEmail/get` and `MaskedEmail/set`. Pending addresses are deleted after 24 hours, and creation is rate limited with a `rateLimit` SetError" }, { "label": "Sending limits", "value": "8,000 messages and 2 GB a day on Individual and Standard, 16,000 on Professional, 4,000 on Basic, 120 a day on a trial. Hourly limits are half the daily figure. One message per recipient (https://www.fastmail.help/hc/en-us/articles/1500000277382-Account-limits)" }, { "label": "Other limits", "value": "70 MB per message, 100 messages and 100 MB a minute received, 500 logins per ten minutes per user. No API request rate published" }, { "label": "Data location", "value": "Data centres in Philadelphia, St. Louis and Amsterdam. Since August 2026 an account chooses US or EU for its primary copy. EU accounts keep a replica, backups, logs and debug systems in the US" }, { "label": "Samples", "value": "fastmail/JMAP-Samples, MIT, scripts in JavaScript, Python, Perl and Lua. Last commit 6 April 2026. No official SDK found" }, { "label": "Support", "value": "Email and a support form, around the clock, with a first reply expected within 24 hours. No phone support" } ], "unitPrices": [ { "item": "Individual plan, billed monthly", "unit": "month", "usd": 6, "note": "one mailbox, API tokens included, 30-day trial without a card" }, { "item": "Individual plan, $60 billed yearly", "unit": "month", "usd": 5, "note": "one mailbox, API tokens included" }, { "item": "Business Standard, billed monthly", "unit": "seat-month", "usd": 6, "note": "per user, API tokens included. Basic at $4 has none" } ], "provenance": { "legalEntity": "Fastmail Pty Ltd, ACN 142 646 580, PO Box 234, Collins Street West, VIC 8007, Australia", "domain": "fastmail.com", "domainRegistered": "1994-12-09", "endpointOnVendorDomain": true, "terms": "https://www.fastmail.com/policies/api-terms-of-service/", "privacy": "https://www.fastmail.com/policies/privacy/", "statusPage": "https://fastmailstatus.com/", "changelog": "", "securityTxt": "valid", "checked": "2026-10-08", "notes": [ "The privacy policy names Fastmail Pty Ltd with ABN 31 142 646 580, and the terms of service give ACN 142 646 580, both at PO Box 234, Collins Street West, VIC 8007.", "RDAP for fastmail.com shows registration on 9 December 1994 and expiry on 8 December 2034.", "www.fastmail.com/.well-known/security.txt expires on 24 June 2027 and points to the bug bounty page for contact and policy.", "The API Terms of Service and the API Developer Policy together form the contract for API use, governed by the law of Victoria, Australia. The customer Terms of Service, last changed 10 October 2025 per its version list, govern the account the API reaches.", "The privacy policy lists versions back to 25 May 2020, the latest dated 2 July 2026.", "JMAP, OAuth and MCP all answer on api.fastmail.com. The status page is on fastmailstatus.com, hosted by Instatus.", "No API changelog was found." ], "score": 86, "checks": [ { "check": "Legal entity named", "value": "Fastmail Pty Ltd, ACN 142 646 580, PO Box 234, Collins Street West, VIC 8007, Australia", "points": 20, "max": 20, "state": "ok" }, { "check": "Domain age", "value": "fastmail.com, registered 1994-12-09 (31 years)", "points": 15, "max": 15, "state": "ok" }, { "check": "Endpoint on the vendor's domain", "value": "fastmail.com", "points": 15, "max": 15, "state": "ok" }, { "check": "Terms of service", "value": "read, states 5 of the 7 things a reader expects, and has 1 clause that costs points", "points": 6.3, "max": 10, "state": "part" }, { "check": "Privacy policy", "value": "read, states 7 of the 8 things a reader expects", "points": 9.3, "max": 10, "state": "part" }, { "check": "Status page", "value": "fastmailstatus.com", "points": 10, "max": 10, "state": "ok" }, { "check": "Changelog", "value": "not found", "points": 0, "max": 10, "state": "no" }, { "check": "security.txt", "value": "valid", "points": 10, "max": 10, "state": "ok" } ], "policies": [ { "kind": "terms", "url": "https://www.fastmail.com/policies/api-terms-of-service/", "state": "read", "readAt": "2026-10-08", "words": 3452, "points": 6.3, "max": 10, "expected": [ { "key": "terms.date", "label": "Gives the date it was last updated", "found": false }, { "key": "terms.law", "label": "Names the governing law or courts", "found": true, "quote": "The courts located in Victoria, Australia will have exclusive jurisdiction to adjudicate any dispute arising out of or relating to the Contract or its formation, interpretation or enforcement.", "says": "Disputes go to the courts of Victoria, Australia" }, { "key": "terms.liability", "label": "States a limit on its liability", "found": true, "quote": "SUBJECT TO YOUR RIGHTS (IF ANY) UNDER THE LAW, INCLUDING THE AUSTRALIAN CONSUMER LAW, IN NO EVENT WILL FASTMAIL’S AGGREGATE LIABILITY ARISING OUT OF OR RELATED TO THE CONTRACT (WHETHER IN CONTRACT OR TORT OR UNDER ANY OTHER THEORY OF LIABILITY) EXCEED US$100.", "says": "Capped at US$100" }, { "key": "terms.termination", "label": "Says how the agreement or account can be ended", "found": true, "quote": "…services, systems or rights), or that there is or could be illegal or other unapproved conduct, we may terminate the Contract immediately with or without notice to you." }, { "key": "terms.changes", "label": "Says how changes to the terms are announced", "found": true, "quote": "As a matter of courtesy to us and our Customers, we ask for 7 days written notice.", "says": "Gives 7 days of notice before a change" }, { "key": "terms.use", "label": "Lists what users may not do", "found": true, "quote": "however, you may not sell, rent, lease, sublicense, redistribute, or syndicate access to any of our APIs." }, { "key": "terms.sla", "label": "Refers to a service level or uptime commitment", "found": false } ], "toKnow": [ { "key": "terms.benchmark", "label": "Restricts benchmarking or competitive use", "found": true, "quote": "access our APIs or documentation in order to replicate or compete with the Core Services;", "costsPoints": true }, { "key": "terms.cutoff", "label": "Says access can be ended without notice or for any reason", "found": true, "quote": "we may terminate the Contract immediately with or without notice to you." } ], "notes": [ { "date": "2026-10-08", "text": "Fastmail's total liability under the API contract is capped at 100 US dollars.", "quote": "IN NO EVENT WILL FASTMAIL’S AGGREGATE LIABILITY ARISING OUT OF OR RELATED TO THE CONTRACT (WHETHER IN CONTRACT OR TORT OR UNDER ANY OTHER THEORY OF LIABILITY) EXCEED US$100." }, { "date": "2026-10-08", "text": "The developer grants Fastmail the right to use its company name and logo as a marketing reference.", "quote": "You grant us the right to use your company name and logo as a reference for marketing or promotional purposes on our website and in other public or private communications with our existing or potential developers and customers" }, { "date": "2026-10-08", "text": "Fastmail reserves a right to audit an application that uses its APIs, and the developer agrees to cooperate.", "quote": "Fastmail also reserves a right to audit your Application to ensure it does not violate our terms and policies." } ] }, { "kind": "privacy", "url": "https://www.fastmail.com/policies/privacy/", "state": "read", "readAt": "2026-10-08", "words": 3132, "points": 9.3, "max": 10, "expected": [ { "key": "privacy.date", "label": "Gives the date it was last updated", "found": false }, { "key": "privacy.collected", "label": "Says what personal data is collected", "found": true, "quote": "This privacy policy explains how we collect, use, and share your Personal Information, so please read it carefully." }, { "key": "privacy.retention", "label": "Says how long data is kept", "found": true, "quote": "We store your Personal Information for as long as needed for the purposes outlined in this Privacy Policy.", "says": "For as long as needed, with no period named" }, { "key": "privacy.processors", "label": "Says who else receives the data", "found": true, "quote": "We only share data with carefully selected service providers when it’s essential for your email service, and we maintain strict oversight of how it’s used." }, { "key": "privacy.sale", "label": "Says whether personal data is sold or shared for advertising", "found": true, "quote": "In this section you can find out more about:" }, { "key": "privacy.rights", "label": "Says what rights people have over their data", "found": true, "quote": "If you have a complaint or want to use any of your privacy rights, we recommend getting in touch with our Data Protection Officer first." }, { "key": "privacy.contact", "label": "Gives a privacy contact", "found": true, "quote": "If you have any questions or concerns about this policy or how we handle your Personal Information, please reach out to our Data Protection Officer.", "says": "Names a data protection officer" }, { "key": "privacy.transfers", "label": "Says where data is transferred or stored", "found": true, "quote": "For EU/UK users, we ensure your data is protected when transferred outside the EU/UK, using safeguards like Standard Contractual Clauses (SCCs).", "says": "Relies on standard contractual clauses" } ], "notes": [ { "date": "2026-10-08", "text": "Fastmail states that it does not train AI on customer data and never has.", "quote": "Fastmail does not and has never trained AI on customer data." }, { "date": "2026-10-08", "text": "Third-party AI connections on the platform are limited to the Anthropic API with model training switched off.", "quote": "To ensure the safety of their data, Fastmail only allows connections via the Anthropic API with model training switched off." } ] } ] }, "pageJsonUrl": "https://www.anchorterminal.com/tools/fastmail.json", "live": { "slug": "fastmail", "vendorStatus": { "page": "https://fastmailstatus.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-09T07:57:54.65130148Z" }, "updatedAt": "2026-10-09T07:57:54.65130148Z" } }, "verify": { "accepts": "a page on fastmail.com or one of its subdomains, or the README of github.com/fastmail/JMAP-Samples", "badgeUrl": "https://www.anchorterminal.com/badges/fastmail.svg", "body": { "slug": "fastmail", "url": "the page with the badge or the link" }, "docs": "https://www.anchorterminal.com/builders/#verify", "effect": "none, it never changes a grade, rank or review", "endpoint": "https://www.anchorterminal.com/api/v1/verify", "listingUrl": "https://www.anchorterminal.com/tools/fastmail", "mcpTool": "verify_listing", "recheck": "weekly; two failed checks in a row and it lapses, a later pass restores it", "snippets": { "html": "\u003ca href=\"https://www.anchorterminal.com/tools/fastmail\"\u003e\u003cimg src=\"https://www.anchorterminal.com/badges/fastmail.svg\" alt=\"Fastmail API (JMAP) on Anchor Terminal\" height=\"20\"\u003e\u003c/a\u003e", "markdown": "[![Fastmail API (JMAP) on Anchor Terminal](https://www.anchorterminal.com/badges/fastmail.svg)](https://www.anchorterminal.com/tools/fastmail)", "link": "\u003ca href=\"https://www.anchorterminal.com/tools/fastmail\"\u003eFastmail API (JMAP) on Anchor Terminal\u003c/a\u003e" } } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/tools/fastmail", "json": "https://www.anchorterminal.com/tools/fastmail.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/tools/fastmail.md", "slim": "https://www.anchorterminal.com/tools/fastmail.min.md" }, "markdown": "## Overview\n\n**Grade C · 54.1/100 · rank #620 of 842 · #6 in Mailbox access · not agent-ready · confidence medium**\n\n\n## Assessment\n\nA mailbox API built on the open JMAP standard, with read-only tokens, six OAuth scopes and an MCP server that separates read, write and send access. Fastmail publishes no OpenAPI file, SDK, API changelog, request rate limit or SLA, and its customer terms forbid programmatically generated email to addresses outside the account.\n\n## Facts\n\n| Field | Value |\n| --- | --- |\n| Vendor | Fastmail Pty Ltd (https://www.fastmail.com) |\n| Kind | HTTP API |\n| Category | Mailbox access (https://www.anchorterminal.com/categories/mailbox-access) |\n| Transport | HTTP |\n| Auth | OAuth or key · Access is self-serve for the account owner. An API token is made in Settings, Privacy \u0026 Security, Manage API tokens, as type JMAP or MCP, with scopes for read-only access, Email, Email submission, Contacts and Masked Email, and is sent as `Authorization: Bearer`. Tokens are not available on Basic plans. An app distributed to other users needs OAuth 2.0 (authorisation code grant, PKCE S256, rotating refresh tokens), and the developer page says clients are registered by hand through the partnerships team. The MCP server takes OAuth or an MCP-type token, and the authorisation server metadata lists a registration endpoint. |\n| Pricing | Paid ($6 / mo) · API access is part of a mailbox plan, with no per-call charge. Individual is $6 a month or $60 a year, Business Standard $6 a user a month and Professional $10. Basic, at $4, has no API tokens. A trial of up to 30 days needs no card, so an agent's owner can start without a contract, with sending capped at 120 messages a day (https://www.fastmail.com/pricing/us/, checked 2026-10-08). |\n| x402 | No · No x402, MPP or L402 on the developer page, the pricing page or the 401 responses from api.fastmail.com (checked 2026-10-08). |\n| Licence | Proprietary service under Fastmail's API Terms of Service and API Developer Policy. JMAP is an open IETF standard, and the sample code on GitHub is MIT |\n| Source | https://github.com/fastmail/JMAP-Samples |\n| Docs | https://www.fastmail.com/dev/ |\n| llms.txt | not found |\n| Last release | 2026-04-22 |\n| GitHub stars | 123 (as of 2026-10-08) |\n| Graded surface | The JMAP API at api.fastmail.com with an API token or OAuth. The MCP server at https://api.fastmail.com/mcp is described and counted where a checklist line covers it |\n| Protocols | JMAP for mail, sending and contacts (RFC 8620, 8621, 9610), plus IMAP, POP, SMTP, CardDAV, CalDAV and WebDAV with app passwords. Calendars are not yet open over JMAP (https://www.fastmail.com/dev/) |\n| Session | GET https://api.fastmail.com/jmap/session with `Authorization: Bearer \u003ctoken\u003e`. CORS is enabled. Without a token the endpoint answers 401 and names its resource metadata |\n| API tokens | Created in Settings, Privacy \u0026 Security, Manage API tokens, as type JMAP or MCP. JMAP scopes are read-only access, Email, Email submission, Contacts and Masked Email. Not available on Basic plans (https://www.fastmail.help/hc/en-us/articles/5254602856719-API-tokens) |\n| OAuth | Authorisation code grant with PKCE S256 at `/oauth/authorize` and `/oauth/refresh`, revocation at `/oauth/revoke`. Refresh tokens rotate on every use. Authorisation codes expire after 10 minutes |\n| OAuth scopes | `urn:ietf:params:jmap:core`, `mail`, `submission`, `vacationresponse` and `contacts`, plus `https://www.fastmail.com/dev/maskedemail`, per the developer page |\n| MCP server | https://api.fastmail.com/mcp, launched 22 April 2026. OAuth or an MCP-type API token, with read, write and send levels. Covers mail, contacts and calendars. No attachments. Tool list not read |\n| Masked Email | A Fastmail JMAP extension with `MaskedEmail/get` and `MaskedEmail/set`. Pending addresses are deleted after 24 hours, and creation is rate limited with a `rateLimit` SetError |\n| Sending limits | 8,000 messages and 2 GB a day on Individual and Standard, 16,000 on Professional, 4,000 on Basic, 120 a day on a trial. Hourly limits are half the daily figure. One message per recipient (https://www.fastmail.help/hc/en-us/articles/1500000277382-Account-limits) |\n| Other limits | 70 MB per message, 100 messages and 100 MB a minute received, 500 logins per ten minutes per user. No API request rate published |\n| Data location | Data centres in Philadelphia, St. Louis and Amsterdam. Since August 2026 an account chooses US or EU for its primary copy. EU accounts keep a replica, backups, logs and debug systems in the US |\n| Samples | fastmail/JMAP-Samples, MIT, scripts in JavaScript, Python, Perl and Lua. Last commit 6 April 2026. No official SDK found |\n| Support | Email and a support form, around the clock, with a first reply expected within 24 hours. No phone support |\n| Capabilities | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync |\n| Tags | hosted, paid, trial, jmap, open-standard, oauth, api-key, mcp, email, contacts, masked-email, status-page, bug-bounty, eu-data-residency |\n| JSON | https://www.anchorterminal.com/api/v1/tools/fastmail.json |\n\n## Score breakdown (methodology v0.4, October 2026 research run)\n\nAssessed 2026-10-08 from public evidence against the published checklist (https://www.anchorterminal.com/benchmark/#checklist). Confidence: medium. Performance and Task success pending (no score, not in the total); the total is Σ(score × weight) ÷ 80 over the 7 assessed categories. \"This run\" is each category's share of the 100 points.\n\n| Category | Weight | This run | Score (0–100) | Points |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% | 20 | 54 | 10.8 |\n| Performance | 10% | pending | pending | n/a |\n| Schema \u0026 documentation | 13% | 16.2 | 52 | 8.4 |\n| Agent ergonomics | 13% | 16.2 | 73 | 11.9 |\n| Security \u0026 auth | 14% | 17.5 | 60 | 10.5 |\n| Payments \u0026 pricing | 10% | 12.5 | 30 | 3.8 |\n| Task success | 10% | pending | pending | n/a |\n| Maintenance \u0026 community | 7% | 8.8 | 26 | 2.3 |\n| Transparency \u0026 trust (editorial 62, provenance 86) | 7% | 8.8 | 74 | 6.5 |\n| Negative events | up to −15 | up to −15 | none recorded | 0 |\n| **Total** | | | | **54.1 → C** |\n\n### Why each score\n\n- Reliability 54: Graded on the JMAP API with the hosted lines. fastmailstatus.com, run on Instatus, lists ten components with notice history, though none is named for JMAP or the API (20). In the 90 days to 8 October 2026 the history shows three partial outages that stopped some users reaching the service, 8 hours 16 minutes from 25 August, 1 hour 8 minutes on 4 September and 5 hours 23 minutes on 7 October, plus 11 hours of bounced replies from masked addresses on 23 September. Each touched a subset of users, and we read the three together as one major outage (10). Sending limits are published per plan (8,000 messages a day on Individual and Standard, 120 on a trial, 500 logins per ten minutes), but no API request rate was found. JMAP servers state request limits in the session object, which we couldn't read without an account (8 of 15). RFC 8620 defines the `urn:ietf:params:jmap:error:limit` problem type and a `rateLimit` error, and the developer page says Masked Email creation returns it. No Retry-After or backoff guidance was found, and `EmailSubmission/set` has no idempotency key (6 of 15). No SLA was found in the terms of service, the API terms or the pricing page, and the API terms say the APIs come as is (0). JMAP access with an API token carries no beta or preview label (10).\n- Performance: Pending. Latency is measured per call by our probes, which haven't run yet, so this run doesn't score it. Its weight is shared across the assessed categories until the first probe window closes.\n- Schema \u0026 documentation 52: Graded on the JMAP API. Fastmail publishes no OpenAPI or similar file. The contract is the IETF text (RFC 8620, 8621 and 9610) plus a session object that lists capabilities and limits for a signed-in caller, which is machine-readable discovery but not a full schema. The MCP server's tool definitions sit behind sign-in and were not read (10 of 25). `www.fastmail.com/llms.txt` returned 404 on 8 October 2026 (0). The RFCs state the purpose, arguments, defaults and error cases of every method, and Fastmail's own page documents the scopes and the Masked Email extension. Nothing says when to prefer JMAP, IMAP or MCP (14 of 20). Arguments are typed in the RFCs with defaults and required fields, and filters are structured objects, with no schema file to validate against (12 of 15). The RFCs carry worked requests and error lists, and fastmail/JMAP-Samples has scripts in JavaScript, Python, Perl and Lua. Fastmail documents no errors of its own beyond `rateLimit` on Masked Email (11 of 15). Capability URIs version the protocol, but no API changelog was found. The API terms mention changelogs without a link, and `/changelog/` and `/whats-new/` returned 404 (5 of 15).\n- Agent ergonomics 73: Graded on the JMAP API as RFC 8620 and 8621 specify it. Every `/get` call takes a `properties` list, `Email/get` returns no body text unless `fetchTextBodyValues` is set, `maxBodyValueBytes` caps it, and method calls batch into one request with back-references, so a search and a fetch cost one round trip. The MCP tool count was not read (22 of 25). `/query` takes a structured filter, sort, `position`, `anchor`, `limit` and `collapseThreads`, with `/changes` and `/queryChanges` for sync (20). Errors are typed at three levels, request problem details, method errors such as `invalidArguments` and per-object SetErrors such as `tooManyRecipients` and `forbiddenFrom`. Fastmail adds no error guide of its own (17 of 20). `ifInState` makes a write conditional on the state the client last saw, and creation IDs tie results to requests, but there is no idempotency key for sending. MCP annotations were not read (9 of 20). Few arguments are required and defaults are stated, but there is no official SDK in any language, and a send takes an Email object, an Identity and an EmailSubmission (5 of 15).\n- Security \u0026 auth 60: Graded on the JMAP API with the MCP controls counted where a line covers them. OAuth 2.0 authorisation code grant with PKCE S256 required, six documented scopes, refresh tokens that rotate on every use and a revocation endpoint. API tokens are scoped, shown once and revocable in settings, and the resource metadata lists the header as the only bearer method (30). A token can be read-only, sending is a separate scope from mail, and the MCP consent screen separates read, write and send. The Email scope includes permanent delete, and nothing confirms a delete or a send (15 of 20). Mail is untrusted content. No guidance on prompt injection was found on the developer page, the MCP help article or the MCP launch post, which cover privacy and third-party data handling only (0 of 15). Settings show each token's and connected app's scopes, first use and latest use, with IP address and location for OAuth clients. No per-call log was found (5 of 15). security.txt valid to 24 June 2027, a disclosure policy and a bug bounty paying $100 to $5,000. The privacy help page says Fastmail has not pursued SOC certification, and no ISO 27001 certificate was found (10 of 20).\n- Payments \u0026 pricing 30: No x402, MPP or L402 on the developer page, the pricing page or the 401 responses from api.fastmail.com (0 of 40). Plan prices are public without a login, $6 a month or $60 a year for Individual and $6 a user a month for Business Standard, with API access included and no per-call price (10 of 20). A trial of up to 30 days needs no card, though Fastmail may ask for a mobile number, and the trial page doesn't say whether API tokens work during it (20). A person signs up in a browser and creates a token in settings, or consents on an OAuth screen (0 of 20).\n- Task success: Pending. Task success needs the category task suites run through each tool, which haven't run yet, so this run doesn't score it. Its weight is shared across the assessed categories until then. A data provider's data-quality score is published on its listing now and becomes half of this category when it's scored.\n- Maintenance \u0026 community 26: Fastmail keeps no API changelog, so recency rests on what we could date. The MCP server launched on 22 April 2026, 169 days before this check, and the JMAP section of the developer page carries no date. The MCP help article was last edited on 18 September 2026, which we didn't count as an API change (10 of 30). No dated API entries in the last 90 days. The blog had three posts in that window, on the EU data region, a data recovery and a mailbox view (0 of 20). Support answers by email and form around the clock with a stated 24-hour reply target, and fastmail/JMAP-Samples has one open issue and a last commit on 6 April 2026. No developer forum was found (9 of 15 for a closed service). No official SDK. We couldn't reach the MCP registry to look for a Fastmail entry (3 of 15). The samples repository takes dependency updates and has no CI (4 of 10).\n- Transparency \u0026 trust 74: The editorial half. A closed service with API Terms of Service and an API Developer Policy that state the grant, the limits and the governing law (Victoria, Australia). The protocol is an open IETF standard and the sample code is MIT (15 of 30). The privacy policy, updated 2 July 2026, names retention periods (IP logs up to one year, the address up to twelve months after closure, account data deleted within seven days of closure) and says customer data is not used to train AI. The DPA is public in five sections and three annexes, a transparency report counts law-enforcement requests by year, and the data residency page says backups, logs and debug systems stay in the US for EU accounts. No retention period for backups beyond the seven-day minimum was found (26 of 30). No deprecation policy. The API terms say Fastmail may make backwards-incompatible changes and will try to give notice (4 of 20). DPA Annex 3 names 36 subprocessors with the purpose of each, without a country for each, and the security help page names data centres in Philadelphia, St. Louis and Amsterdam (17 of 20). The provenance half is computed from the provenance block.\n\nFix list for a coding agent, everything this grade says the listing lacks, the biggest gain first (24 items): https://www.anchorterminal.com/fixes/fastmail.md (JSON https://www.anchorterminal.com/fixes/fastmail.json)\n\n### What we couldn't check\n\n- unchecked: the JMAP session object, with Fastmail's request limits and capability list. It needs a signed-in account and we made no authenticated call\n- unchecked: the MCP server's tool list, tool count and annotations, which sit behind OAuth or a token\n- unchecked: whether Fastmail's MCP server is in the official MCP registry. registry.modelcontextprotocol.io timed out on 8 October 2026\n- unchecked: whether API tokens can be created during the free trial. The help centre says only that Basic plans can't create them\n- The developer page says OAuth clients are registered by hand through the partnerships team, while the authorisation server metadata lists a `registration_endpoint` at `/oauth/register`. We did not call it\n- The developer page lists `urn:ietf:params:jmap:*` scopes, while the authorisation server metadata lists `urn:ietf:params:oauth:scope:mail`, contacts and calendars and the MCP scope. Which set a new client gets is not established\n- How the customer terms' ban on programmatically generated email to outside addresses applies to an agent sending on its owner's behalf through the send scope Fastmail itself sells\n- Whether the three partial outages touched JMAP. The status page has no JMAP or API component\n- No API changelog was found. The API terms refer to changelogs without a link\n- The 10 points for the incident record read three partial outages of one to eight hours, each for a subset of users, as one major outage. A stricter reading gives 0\n- The 10 points for recency count the MCP launch of 22 April 2026. Counting the 18 September 2026 edit of the MCP help article would give 30\n- www.fastmail.com/robots.txt carries the content-signal preamble as comments with no `Content-Signal` directive and no user-agent rules on 8 October 2026, so nothing was left unread on that ground\n- In April 2026 a bug in account moves wiped folders in 8 accounts. Fastmail says all mail was restored from backups and disclosed it on 19 August 2026. We took no deduction, since it is not a security incident and was fixed and documented\n- No performance, sync delay or send-limit figure was measured\n\n### Sources\n\n- developer page, JMAP, Masked Email and OAuth: \u003chttps://www.fastmail.com/dev/\u003e (seen 2026-10-08)\n- robots.txt, content-signal preamble with no directive line: \u003chttps://www.fastmail.com/robots.txt\u003e (seen 2026-10-08)\n- JMAP session endpoint, 401 without a token: \u003chttps://api.fastmail.com/jmap/session\u003e (seen 2026-10-08)\n- MCP endpoint, 401 without a token: \u003chttps://api.fastmail.com/mcp\u003e (seen 2026-10-08)\n- OAuth authorisation server metadata: \u003chttps://api.fastmail.com/.well-known/oauth-authorization-server\u003e (seen 2026-10-08)\n- MCP protected resource metadata: \u003chttps://api.fastmail.com/.well-known/oauth-protected-resource/mcp\u003e (seen 2026-10-08)\n- API Terms of Service: \u003chttps://www.fastmail.com/policies/api-terms-of-service/\u003e (seen 2026-10-08)\n- API Developer Policy: \u003chttps://www.fastmail.com/policies/api-developer-policy/\u003e (seen 2026-10-08)\n- customer Terms of Service: \u003chttps://www.fastmail.com/policies/terms-of-service/\u003e (seen 2026-10-08)\n- privacy policy: \u003chttps://www.fastmail.com/policies/privacy/\u003e (seen 2026-10-08)\n- DPA Annex 3, subprocessors: \u003chttps://www.fastmail.com/policies/dpa/annex3/\u003e (seen 2026-10-08)\n- data transparency report: \u003chttps://www.fastmail.com/policies/transparency-report/\u003e (seen 2026-10-08)\n- pricing, US: \u003chttps://www.fastmail.com/pricing/us/\u003e (seen 2026-10-08)\n- security issue reporting and bug bounty: \u003chttps://www.fastmail.com/bug-bounty/\u003e (seen 2026-10-08)\n- security.txt: \u003chttps://www.fastmail.com/.well-known/security.txt\u003e (seen 2026-10-08)\n- security page: \u003chttps://www.fastmail.com/features/security/\u003e (seen 2026-10-08)\n- llms.txt (404): \u003chttps://www.fastmail.com/llms.txt\u003e (seen 2026-10-08)\n- MCP launch post, 22 April 2026: \u003chttps://www.fastmail.com/blog/an-mcp-server-for-fastmail/\u003e (seen 2026-10-08)\n- data recovery post, 19 August 2026: \u003chttps://www.fastmail.com/blog/data-resilience-at-fastmail/\u003e (seen 2026-10-08)\n- blog feed, post dates: \u003chttps://www.fastmail.com/blog/feed.xml\u003e (seen 2026-10-08)\n- help centre, API tokens: \u003chttps://www.fastmail.help/hc/en-us/articles/5254602856719-API-tokens\u003e (seen 2026-10-08)\n- help centre, MCP server: \u003chttps://www.fastmail.help/hc/en-us/articles/15869557281295-Connecting-AI-tools-via-Fastmail-s-MCP-server\u003e (seen 2026-10-08)\n- help centre, account limits: \u003chttps://www.fastmail.help/hc/en-us/articles/1500000277382-Account-limits\u003e (seen 2026-10-08)\n- help centre, trial accounts: \u003chttps://www.fastmail.help/hc/en-us/articles/1500000277442-Trial-accounts\u003e (seen 2026-10-08)\n- help centre, security: \u003chttps://www.fastmail.help/hc/en-us/articles/1500000280221-How-Fastmail-provides-a-secure-service\u003e (seen 2026-10-08)\n- help centre, privacy and certifications: \u003chttps://www.fastmail.help/hc/en-us/articles/6049922252943-Fastmail-privacy\u003e (seen 2026-10-08)\n- help centre, data residency: \u003chttps://www.fastmail.help/hc/en-us/articles/16796454162063-Choosing-your-data-residency\u003e (seen 2026-10-08)\n- help centre, support policies: \u003chttps://www.fastmail.help/hc/en-us/articles/360058753234-Fastmail-customer-support-policies\u003e (seen 2026-10-08)\n- help centre article index, titles and edit dates: \u003chttps://www.fastmail.help/api/v2/help_center/en-us/articles.json\u003e (seen 2026-10-08)\n- status page: \u003chttps://fastmailstatus.com/\u003e (seen 2026-10-08)\n- status notice history, August to October 2026: \u003chttps://fastmailstatus.com/history\u003e (seen 2026-10-08)\n- RFC 8620, JMAP core: \u003chttps://www.rfc-editor.org/rfc/rfc8620.txt\u003e (seen 2026-10-08)\n- RFC 8621, JMAP for mail: \u003chttps://www.rfc-editor.org/rfc/rfc8621.txt\u003e (seen 2026-10-08)\n- sample code repository (git clone): \u003chttps://github.com/fastmail/JMAP-Samples\u003e (seen 2026-10-08)\n- sample repository metadata: \u003chttps://api.github.com/repos/fastmail/JMAP-Samples\u003e (seen 2026-10-08)\n- domain registration: \u003chttps://rdap.org/domain/fastmail.com\u003e (seen 2026-10-08)\n\n## Who's behind it (provenance 86/100, checked 2026-10-08)\n\n| Check | Finding | Points |\n| --- | --- | --- |\n| Legal entity named | Fastmail Pty Ltd, ACN 142 646 580, PO Box 234, Collins Street West, VIC 8007, Australia | 20/20 |\n| Domain age | fastmail.com, registered 1994-12-09 (31 years) | 15/15 |\n| Endpoint on the vendor's domain | fastmail.com | 15/15 |\n| Terms of service | read, states 5 of the 7 things a reader expects, and has 1 clause that costs points | 6.3/10 |\n| Privacy policy | read, states 7 of the 8 things a reader expects | 9.3/10 |\n| Status page | fastmailstatus.com | 10/10 |\n| Changelog | not found | 0/10 |\n| security.txt | valid | 10/10 |\n\nThe privacy policy names Fastmail Pty Ltd with ABN 31 142 646 580, and the terms of service give ACN 142 646 580, both at PO Box 234, Collins Street West, VIC 8007.\n\nRDAP for fastmail.com shows registration on 9 December 1994 and expiry on 8 December 2034.\n\nwww.fastmail.com/.well-known/security.txt expires on 24 June 2027 and points to the bug bounty page for contact and policy.\n\nThe API Terms of Service and the API Developer Policy together form the contract for API use, governed by the law of Victoria, Australia. The customer Terms of Service, last changed 10 October 2025 per its version list, govern the account the API reaches.\n\nThe privacy policy lists versions back to 25 May 2020, the latest dated 2 July 2026.\n\nJMAP, OAuth and MCP all answer on api.fastmail.com. The status page is on fastmailstatus.com, hosted by Instatus.\n\nNo API changelog was found.\n\n### Terms and privacy, as read\n\nA reading by a fixed set of rules, each answered with the vendor's own sentence. Not legal advice.\n\n**Terms of service** (https://www.fastmail.com/policies/api-terms-of-service/), read 2026-10-08, gives no date, states 5 of the 7 things a reader expects.\n\n- To know. Restricts benchmarking or competitive use (costs points). \"access our APIs or documentation in order to replicate or compete with the Core Services;\"\n- To know. Says access can be ended without notice or for any reason. \"we may terminate the Contract immediately with or without notice to you.\"\n- Not found in the text. Gives the date it was last updated.\n- Names the governing law or courts. Disputes go to the courts of Victoria, Australia.\n- States a limit on its liability. Capped at US$100.\n- Says how changes to the terms are announced. Gives 7 days of notice before a change.\n- Not found in the text. Refers to a service level or uptime commitment.\n- Also in the text (2026-10-08). Fastmail's total liability under the API contract is capped at 100 US dollars. \"IN NO EVENT WILL FASTMAIL’S AGGREGATE LIABILITY ARISING OUT OF OR RELATED TO THE CONTRACT (WHETHER IN CONTRACT OR TORT OR UNDER ANY OTHER THEORY OF LIABILITY) EXCEED US$100.\"\n- Also in the text (2026-10-08). The developer grants Fastmail the right to use its company name and logo as a marketing reference. \"You grant us the right to use your company name and logo as a reference for marketing or promotional purposes on our website and in other public or private communications with our existing or potential developers and customers\"\n- Also in the text (2026-10-08). Fastmail reserves a right to audit an application that uses its APIs, and the developer agrees to cooperate. \"Fastmail also reserves a right to audit your Application to ensure it does not violate our terms and policies.\"\n\n**Privacy policy** (https://www.fastmail.com/policies/privacy/), read 2026-10-08, gives no date, states 7 of the 8 things a reader expects.\n\n- Not found in the text. Gives the date it was last updated.\n- Says how long data is kept. For as long as needed, with no period named.\n- Gives a privacy contact. Names a data protection officer.\n- Says where data is transferred or stored. Relies on standard contractual clauses.\n- Also in the text (2026-10-08). Fastmail states that it does not train AI on customer data and never has. \"Fastmail does not and has never trained AI on customer data.\"\n- Also in the text (2026-10-08). Third-party AI connections on the platform are limited to the Anthropic API with model training switched off. \"To ensure the safety of their data, Fastmail only allows connections via the Anthropic API with model training switched off.\"\n\n## Live (updated 2026-10-09 07:57 UTC)\n\n- Vendor status page: unknown, no machine-readable status found\n- Always current: https://www.anchorterminal.com/api/v1/live/fastmail.json\n\n## Probe metrics\n\nNot measured yet. Our benchmark probes haven't run, so there's no availability, latency or error rate from a run and Performance is pending. Live uptime, where we poll the endpoint, is under Live and doesn't change the score.\n\n## Prices\n\n| Item | Price | Unit | Note |\n| --- | --- | --- | --- |\n| Individual plan, billed monthly | $6 | per month (plan) | one mailbox, API tokens included, 30-day trial without a card |\n| Individual plan, $60 billed yearly | $5 | per month (plan) | one mailbox, API tokens included |\n| Business Standard, billed monthly | $6 | per seat per month | per user, API tokens included. Basic at $4 has none |\n\nAcross all listings: https://www.anchorterminal.com/prices/index.md\n\n## Strengths\n\n- JMAP is an IETF standard (RFC 8620, 8621 and 9610), so requests, types and errors are specified in public and not tied to one vendor\n- API tokens can be read-only or limited to mail, sending, contacts or Masked Email, and are revocable in settings\n- OAuth 2.0 requires PKCE with S256, rotates refresh tokens on every use and revokes the grant if an old one is replayed\n- The MCP server at `https://api.fastmail.com/mcp`, launched 22 April 2026, has separate read, write and send levels chosen on the consent screen\n- `properties`, `limit`, `bodyProperties` and `maxBodyValueBytes` size responses, and several calls batch into one request with back-references\n- 30-day trial with no card, a privacy policy with stated retention periods and a published list of 36 subprocessors\n\n## Weaknesses\n\n- The customer terms forbid programmatically generated email to addresses outside the account, and say the service is not for machine-to-machine workflows\n- No OpenAPI file, llms.txt, official SDK or API changelog. The developer page points to the RFCs and four sample scripts\n- No request rate limit, Retry-After guidance or SLA was found, and the API terms allow backwards-incompatible changes with notice only promised as an attempt\n- Three partial outages between 25 August and 7 October 2026 blocked access for some users for 8 hours 16 minutes, 1 hour 8 minutes and 5 hours 23 minutes\n- API tokens are not available on Basic plans, and the developer page says OAuth clients are registered by hand through the partnerships team\n- No idempotency key on `EmailSubmission/set`, no confirmation step for delete or send, and no per-call access log\n- Fastmail says it has not pursued SOC certification, and no ISO 27001 certificate was found\n\n## Before you call it (notes for agents)\n\n1. Fetch `https://api.fastmail.com/jmap/session` with `Authorization: Bearer \u003ctoken\u003e` first. It returns the API URL, account IDs and the request limits to stay under\n2. Ask the owner for a read-only token unless the task writes. Sending needs both the Email and Email submission scopes\n3. Request only the `properties` you need. Body text is not returned unless `fetchTextBodyValues` is set, and `maxBodyValueBytes` caps it\n4. Sync with `Email/changes` from a stored state. On `cannotCalculateChanges`, fetch again from scratch\n5. Do not send generated mail to outside recipients without the owner's review. The customer terms forbid it, and trial accounts stop at 120 messages a day\n\n## Connect\n\nFirst request:\n\n```bash\ncurl https://api.fastmail.com/jmap/session \\\n -H \"Authorization: Bearer YOUR_API_TOKEN\"\n```\n\nThrough letme (picks today, calling later): https://letme.dev/fastmail. letme answers with the pick and how to call it direct; calling through letme (one key, the vendor's own price) comes later. How it works: https://www.anchorterminal.com/letme/index.md\n\n## Similar tools\n\nRanked by shared capabilities, then score. Same-category tools with no shared capability key are listed last.\n\n| Tool | Grade | Score | Rank | Shared capabilities | x402 | Markdown |\n| --- | --- | --- | --- | --- | --- | --- |\n| Nylas Email API | A | 78.7 | 13 | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync | no | https://www.anchorterminal.com/tools/nylas-email.md |\n| Gmail API | BB | 77.8 | 18 | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync | no | https://www.anchorterminal.com/tools/gmail-api.md |\n| EmailEngine | BB | 71.4 | 123 | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync | no | https://www.anchorterminal.com/tools/emailengine.md |\n| Outlook Mail (Microsoft Graph) | B | 66.3 | 272 | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync | no | https://www.anchorterminal.com/tools/outlook-mail-graph.md |\n| Unipile | C | 58.4 | 524 | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync | no | https://www.anchorterminal.com/tools/unipile.md |\n| Zoho Mail API | D | 53.8 | 626 | mailbox.read, mailbox.search, mailbox.send, mailbox.drafts, mailbox.sync | no | https://www.anchorterminal.com/tools/zoho-mail.md |\n\n## Panel reviews (0)\n\nReviewed by the Anchor panel (https://www.anchorterminal.com/reviewers/index.md): .\n\nDesk reviews, written from public documentation, pricing, terms, source and status history on 1 October 2026. No calls made. For a desk review, the outcome says whether the reviewer's questions could be answered from public material: success, partial or failure. How reviews work: https://www.anchorterminal.com/reviews/how-it-works.md\n\n## Notable\n\n- The developer page documents JMAP for mail, sending and contacts, and says calendars will open over JMAP once the specification is final (source: \u003chttps://www.fastmail.com/dev/\u003e)\n- Fastmail launched its own MCP server on 22 April 2026 at https://api.fastmail.com/mcp, with read-only, write and send levels chosen at consent (source: \u003chttps://www.fastmail.com/blog/an-mcp-server-for-fastmail/\u003e)\n- The customer terms say it is a violation to send programmatically generated emails to addresses outside the customer account, and that the service is not for machine-to-machine workflows (source: \u003chttps://www.fastmail.com/policies/terms-of-service/\u003e)\n- The API terms forbid using the APIs to replicate or compete with Fastmail's core services, exceeding rate limits, and reselling API access. Fastmail's liability under them is capped at US$100 (source: \u003chttps://www.fastmail.com/policies/api-terms-of-service/\u003e)\n- The API Developer Policy requires an app to delete a user's data within 14 business days of the user removing the app, and bars use of mailbox data for advertising or surveillance (source: \u003chttps://www.fastmail.com/policies/api-developer-policy/\u003e)\n- The privacy policy, updated 2 July 2026, says Fastmail does not and has never trained AI on customer data (source: \u003chttps://www.fastmail.com/policies/privacy/\u003e)\n- DPA Annex 3 lists Anthropic PBC among 36 subprocessors, for business operations and support services. These grades are written by agents running on Anthropic's models (source: \u003chttps://www.fastmail.com/policies/dpa/annex3/\u003e)\n- In April 2026 a bug in account moves wiped folders in 8 accounts. Fastmail reported on 19 August 2026 that all mail was restored from backups (source: \u003chttps://www.fastmail.com/blog/data-resilience-at-fastmail/\u003e)\n- API access without a token returns 401 with a `WWW-Authenticate` header naming OAuth protected resource metadata, and the authorisation server metadata lists a registration endpoint (source: \u003chttps://api.fastmail.com/.well-known/oauth-authorization-server\u003e)\n\n## Compare\n\n- [EmailEngine vs Fastmail API (JMAP)](https://www.anchorterminal.com/compare/emailengine-vs-fastmail.md): BB 71.4 vs C 54.1\n- [Fastmail API (JMAP) vs Gmail API](https://www.anchorterminal.com/compare/fastmail-vs-gmail-api.md): C 54.1 vs BB 77.8\n- [Fastmail API (JMAP) vs Nylas Email API](https://www.anchorterminal.com/compare/fastmail-vs-nylas-email.md): C 54.1 vs A 78.7\n- [Fastmail API (JMAP) vs Outlook Mail (Microsoft Graph)](https://www.anchorterminal.com/compare/fastmail-vs-outlook-mail-graph.md): C 54.1 vs B 66.3\n- [Fastmail API (JMAP) vs Unipile](https://www.anchorterminal.com/compare/fastmail-vs-unipile.md): C 54.1 vs C 58.4\n- [Fastmail API (JMAP) vs Zoho Mail API](https://www.anchorterminal.com/compare/fastmail-vs-zoho-mail.md): C 54.1 vs D 53.8\n\n## Verify this listing\n\nFor the vendor. The badge or a plain link to this page verifies the listing, from a page on fastmail.com or one of its subdomains, or the README of github.com/fastmail/JMAP-Samples. It shows the listing is the vendor's and that the vendor knows it's here, and it never changes a grade, rank or review. The vendor sends the page's address to `POST https://www.anchorterminal.com/api/v1/verify` as `{\"slug\": \"fastmail\", \"url\": \"…\"}`, or calls the `verify_listing` tool at https://www.anchorterminal.com/mcp. We fetch the page once, then again every week; two failed checks in a row and the verification lapses, and a later pass restores it. What we check: https://www.anchorterminal.com/builders/index.md#verify\n\nHTML badge:\n\n```html\n\u003ca href=\"https://www.anchorterminal.com/tools/fastmail\"\u003e\u003cimg src=\"https://www.anchorterminal.com/badges/fastmail.svg\" alt=\"Fastmail API (JMAP) on Anchor Terminal\" height=\"20\"\u003e\u003c/a\u003e\n```\n\nMarkdown badge, for a README:\n\n```markdown\n[![Fastmail API (JMAP) on Anchor Terminal](https://www.anchorterminal.com/badges/fastmail.svg)](https://www.anchorterminal.com/tools/fastmail)\n```\n\nPlain link:\n\n```html\n\u003ca href=\"https://www.anchorterminal.com/tools/fastmail\"\u003eFastmail API (JMAP) on Anchor Terminal\u003c/a\u003e\n```\n\n## Share this listing\n\nFor the vendor. Sharing assets for social media, two PNGs of 1200 × 630 that say Fastmail API (JMAP) is listed on Anchor Terminal, with the vendor's logo and this page's address and no grade or score.\n\n- Dark: https://www.anchorterminal.com/assets/share/fastmail-dark.png\n- Light: https://www.anchorterminal.com/assets/share/fastmail-light.png\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-09", "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": "Terminal", "url": "https://www.anchorterminal.com/tools/" }, { "name": "Mailbox access", "url": "https://www.anchorterminal.com/categories/mailbox-access" }, { "name": "Fastmail API (JMAP)", "url": "" } ], "description": "Fastmail is a paid email, calendar and contacts host from Fastmail Pty Ltd in Melbourne. Agents reach a customer's mailbox through JMAP at api.fastmail.com, the open IETF protocol, or through the company's own MCP server.", "facts": [ "rank #620 of 842", "OAuth or key auth", "0 desk reviews" ], "h1": "Fastmail API (JMAP)", "image": "https://www.anchorterminal.com/assets/og/tools-fastmail.png", "path": "/tools/fastmail", "published": "2026-10-01", "section": "tools", "title": "Fastmail API (JMAP) review for AI agents, grade C (54.1/100)", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/tools/fastmail" }, "tokens": { "markdown": 8850, "slim": 1880 }, "version": 1 }