{ "data": { "a": { "slug": "mailpace", "name": "MailPace", "vendor": "OhMySMTP Ltd", "vendorUrl": "https://mailpace.com", "kind": "http-api", "category": "email", "summary": "MailPace is a UK transactional email service, formerly OhMySMTP, hosted in the EU. It sends mail through an HTTPS API or SMTP, turns inbound mail into webhooks and has a Domains and Email Status API.", "url": "https://www.anchorterminal.com/tools/mailpace", "markdownUrl": "https://www.anchorterminal.com/tools/mailpace.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/mailpace.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/mailpace.json", "dns": "mailpace.grade.anchorterminal.com", "repo": "https://github.com/mailpace/mailpace-mcp", "transports": [ "http" ], "packages": [ { "registry": "npm", "name": "@mailpace/mailpace.js" } ], "auth": "api-key", "authNotes": "Each domain has its own server token, sent in the `MailPace-Server-Token` header, which can send from that domain and read its email status. An organisation token in `MailPace-Organization-Token` manages domains and domain tokens through the Domains API, including revoking them. Both are made in the dashboard after a browser signup.", "pricing": "paid", "pricingNotes": "$10 a month includes 10,000 emails sent or received, then $1 per 1,000, per the Paddle prices the pricing page loads and the comparison pages ($100 for 100,000, $1,000 for 1 million). A free plan of up to 100 emails a month is given on request by email. Paddle is the merchant of record; card, PayPal, Apple Pay or Google Pay.", "priceSummary": "$10 / mo", "where": "local", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the docs repository, the pricing page or the MCP server source (checked 2026-11-06). Payment is by Paddle subscription; the FAQ says crypto isn't accepted.", "endpoints": [] }, "toolCount": 12, "popularity": { "githubStars": 1, "npmWeekly": 207, "pypiWeekly": null, "asOf": "2026-11-06" }, "docsUrl": "https://docs.mailpace.com/", "capabilities": [ "email.send", "email.inbound", "email.domains", "email.analytics" ], "tags": [ "hosted", "closed-source", "smtp", "webhooks", "idempotency", "status-page", "sla", "eu", "mcp", "typescript", "ruby", "go", "php" ], "lastRelease": "2026-10-22", "graded": true, "anchor": { "graded": true, "score": 58.4, "grade": "C", "agentReady": false, "rank": 750, "ranked": true, "rankOf": 1486, "categoryRank": 17, "methodology": "0.7", "run": "2026-10-01", "scores": { "ergonomics": 71, "maintenance": 65, "payments": 25, "reliability": 70, "schema": 54, "security": 50, "transparency": 75 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-11-06" }, "negative": 0, "verdict": "A small transactional sender with idempotent sends, signed webhooks, a 99% availability promise in its terms and a public Upptime status record. There is no OpenAPI spec, no published rate limit, no llms.txt, and its MCP server was rewritten on 4 November 2026 but isn't on npm or in the MCP registry yet.", "bestFor": "Low-volume transactional mail from EU-hosted infrastructure with idempotent sends and no tracking.", "strengths": [ "Sends accept an `Idempotency-Key` header kept for 24 hours, so a retry after a timeout doesn't send twice", "Per-domain server tokens limit a leaked key to one domain, and organisation tokens can create and revoke them by API", "Webhooks are signed with Ed25519 and inbound mail is retried five times before it fails", "Status page on Upptime with GitHub issues as incident reports, and a 99% monthly availability promise with credits in the terms", "Sub-processors and their locations are listed, and mail is kept 30 days plus 7 in backups per the DPA" ], "weaknesses": [ "No OpenAPI spec, llms.txt or Markdown docs for agents; the reference is Docusaurus pages", "Rate limits aren't published; the docs say they vary by organisation age, plan and history", "No free plan without emailing support, and the paid plan starts at $10 a month", "MCP server 2.0.0 exists only in the repository; npm and the MCP registry had nothing for it on 6 November 2026", "No security.txt, disclosure policy or certification found" ], "agentNotes": [ "Send a UUID in `Idempotency-Key` on every `POST /api/v1/send`, and reuse it on a retry; keys last 24 hours and are tied to one token", "Use the server token of the sending domain, since the From domain must match the token's domain or the API returns 403", "On 429 `You are sending emails too quickly` back off; no Retry-After is documented", "Send only transactional mail; marketing and bulk newsletters are prohibited by the docs and terms", "Read delivery with `GET /api/v1/domains/:domain_id/emails/:id` using the id the send returned" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.7", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 58.4 } ], "editorialScores": { "ergonomics": 71, "maintenance": 65, "payments": 25, "reliability": 70, "schema": 54, "security": 50, "transparency": 69 }, "provenanceScore": 81, "checked": { "categories": { "ergonomics": "2026-11-06", "maintenance": "2026-11-06", "payments": "2026-11-06", "reliability": "2026-11-06", "schema": "2026-11-06", "security": "2026-11-06", "transparency": "2026-11-06" }, "last": "2026-11-06", "oldest": "2026-11-06", "stale": false, "staleAfterDays": 90 } }, "connect": { "http": "curl https://app.mailpace.com/api/v1/send -X POST -H \"Accept: application/json\" -H \"Content-Type: application/json\" -H \"MailPace-Server-Token: $MAILPACE_TOKEN\" -H \"Idempotency-Key: $(uuidgen)\" -d '{\"from\":\"you@yourdomain.com\",\"to\":\"person@example.com\",\"subject\":\"Hello\",\"textbody\":\"Hello\"}'" }, "letme": { "capability": "https://letme.dev/email.send", "tool": "https://letme.dev/mailpace" }, "area": "communication", "unitPrices": [ { "item": "Scaling plan", "unit": "month", "usd": 10, "note": "includes 10,000 emails sent or received" }, { "item": "Emails beyond 10,000", "unit": "1k-emails", "usd": 1 } ], "provenance": { "legalEntity": "OhMySMTP Ltd", "domain": "mailpace.com", "domainRegistered": "2022-01-10", "endpointOnVendorDomain": true, "terms": "https://mailpace.com/terms", "privacy": "https://mailpace.com/privacy", "statusPage": "https://status.mailpace.com", "changelog": "https://mailpace.com/category/changelog", "securityTxt": "none", "checked": "2026-11-06", "notes": [ "The terms and privacy policy name OhMySMTP Ltd, incorporated in England and Wales, company number 13200428. Companies House lists two active directors.", "Terms last updated 9 January 2026, privacy policy 30 August 2026, DPA updated in October 2026 per the landing repository.", "mailpace.com/robots.txt allows all paths. The terms contain no clause on automated access to the website beyond the usual licence limits.", "RDAP gives mailpace.com a registration date of 10 January 2022; the service ran as OhMySMTP before that.", "/.well-known/security.txt returns 404 on mailpace.com and app.mailpace.com." ], "score": 81 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/mailpace.json", "live": { "slug": "mailpace", "vendorStatus": { "page": "https://status.mailpace.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-11-07T04:48:01.553362214Z" }, "versions": [ { "registry": "npm", "name": "@mailpace/mailpace.js", "version": "0.1.3", "seenAt": "2026-11-06T23:42:02.752996422Z" } ], "githubStars": 1, "npmWeekly": 207, "securityTxt": { "url": "https://mailpace.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-11-07T16:01:07.630537329Z" }, "pages": [ { "url": "https://mailpace.com/category/changelog", "kind": "changelog", "status": 200, "checkedAt": "2026-11-07T14:13:40.841899008Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "38f92a159d1b" }, { "url": "https://mailpace.com/privacy", "kind": "privacy", "status": 200, "checkedAt": "2026-11-07T14:13:45.28058492Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "e6b0fea49c1d" }, { "url": "https://mailpace.com/terms", "kind": "terms", "status": 200, "checkedAt": "2026-11-07T14:13:45.480605157Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "24f1eed01dad" } ], "updatedAt": "2026-11-07T16:01:07.630537329Z" } }, "answer": "Resend API + MCP scores 78.1 (A) on agent readiness against MailPace's 58.4 (C), and leads in 6 of 7 scored categories.", "b": { "slug": "resend", "name": "Resend API + MCP", "vendor": "Resend", "vendorUrl": "https://resend.com", "kind": "http-api", "category": "email", "summary": "Transactional and marketing email API with inbound receiving, templates, broadcasts and automations.", "url": "https://www.anchorterminal.com/tools/resend", "markdownUrl": "https://www.anchorterminal.com/tools/resend.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/resend.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/resend.json", "dns": "resend.grade.anchorterminal.com", "repo": "https://github.com/resend/resend-mcp", "license": "MIT", "transports": [ "http", "streamable-http", "stdio" ], "remoteUrl": "https://api.resend.com", "packages": [ { "registry": "npm", "name": "resend" }, { "registry": "pypi", "name": "resend" }, { "registry": "npm", "name": "resend-mcp" } ], "auth": "mixed", "authNotes": "Bearer API key (`re_...`) with full or sending-only permissions. Requests without a User-Agent header get a 403. The hosted MCP signs in with OAuth. The local MCP takes the key from `RESEND_API_KEY` or a `--key` flag.", "pricing": "freemium", "pricingNotes": "Free plan with 3,000 emails a month, capped at 100 a day. Pro $20 a month for 50,000 emails or $35 for 100,000, overage $0.90 per 1,000. Scale from $90 for 100,000 to $1,150 for 2,500,000, overage $0.90 down to $0.46 per 1,000. Received emails count towards the quota. Every plan includes 3 inboxes, and paid plans can add more at $1 an inbox a month; inbox mail uses the transactional quota. Marketing is billed by contacts from $40 a month for 5,000. Dedicated IP $30 a month on Scale. Monthly billing only (https://resend.com/pricing.md).", "priceSummary": "$20 / mo", "where": "both", "x402": { "level": "no", "evidence": "No x402 support in docs, pricing or MCP README (checked 2026-09-30).", "endpoints": [] }, "toolCount": 136, "popularity": { "githubStars": 575, "npmWeekly": 13608112, "pypiWeekly": 2840474, "asOf": "2026-09-30" }, "docsUrl": "https://resend.com/docs", "llmsTxt": "https://resend.com/docs/llms.txt", "openapi": "https://raw.githubusercontent.com/resend/resend-openapi/main/resend.yaml", "capabilities": [ "email.send", "email.inbound", "email.templates", "email.domains", "email.analytics", "email.marketing" ], "tags": [ "hosted", "freemium", "no-card", "mcp", "llms-txt", "openapi", "typescript", "python", "webhooks" ], "lastRelease": "2026-10-30", "graded": true, "anchor": { "graded": true, "score": 78.1, "grade": "A", "agentReady": true, "rank": 26, "ranked": true, "rankOf": 1486, "categoryRank": 1, "methodology": "0.7", "run": "2026-10-01", "scores": { "ergonomics": 67, "maintenance": 93, "payments": 50, "reliability": 90, "schema": 95, "security": 69, "transparency": 83 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-11-01" }, "negative": 0, "verdict": "`Idempotency-Key` on POST /emails and /emails/batch, kept for 24 hours. 136 MCP tools load at once, with no toolsets.", "bestFor": "Developers who want an agent to send, receive and manage templates from one MCP, and for teams that value tool descriptions written for models.", "strengths": [ "`Idempotency-Key` on POST /emails and /emails/batch, kept for 24 hours", "MCP tool descriptions that say what each tool is for, what it isn't for and which tool to use instead", "Hosted MCP with OAuth, discoverable through an MCP Server Card, and the same code on npm as resend-mcp under MIT", "Sending-only API keys that can be limited to one domain", "Local file reads by the MCP can be confined to chosen folders, and are off over HTTP by default since 6 October 2026" ], "weaknesses": [ "136 MCP tools load at once, with no toolsets", "No destructiveHint on the 16 older remove, cancel, revoke and rotate tools", "Received mail and inbox threads reach the model through the MCP with no guidance on treating them as untrusted", "Fourteen status incidents from 11 September to 26 October, including a broadcast stall of about two hours on 15 September", "10 requests a second per team by default" ], "agentNotes": [ "Send an `Idempotency-Key` on POST /emails so a retry after a timeout doesn't send twice", "Send a User-Agent header on raw HTTP calls or you'll get a 403", "Give the agent a `sending_access` key limited to one domain unless it has to manage the account", "On 429, wait for `retry-after`, and use /emails/batch to stay under 10 requests a second", "Run resend-mcp 2.25.0 or later, and on stdio set `--allowed-file-dirs` so an injected prompt can't attach files from elsewhere on disk" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 8, "avgRating": 3.4, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "A", "methodology": "0.7", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 78.1 } ], "editorialScores": { "ergonomics": 67, "maintenance": 93, "payments": 50, "reliability": 90, "schema": 95, "security": 69, "transparency": 70 }, "provenanceScore": 96, "checked": { "categories": { "ergonomics": "2026-11-01", "maintenance": "2026-11-01", "payments": "2026-11-01", "reliability": "2026-11-01", "schema": "2026-11-01", "security": "2026-11-01", "transparency": "2026-11-01" }, "last": "2026-11-01", "lastMoved": "2026-11-01", "oldest": "2026-11-01", "stale": false, "staleAfterDays": 90 } }, "connect": { "http": "curl -X POST https://api.resend.com/emails -H \"Authorization: Bearer $RESEND_API_KEY\" \\\n -H \"Content-Type: application/json\" \\\n -d '{\"from\":\"onboarding@resend.dev\",\"to\":[\"delivered@resend.dev\"],\"subject\":\"Hello\",\"html\":\"\u003cp\u003eIt works\u003c/p\u003e\"}'", "claudeCode": "claude mcp add --transport http resend https://mcp.resend.com/mcp", "config": { "mcpServers": { "resend": { "args": [ "-y", "resend-mcp" ], "command": "npx", "env": { "RESEND_API_KEY": "${RESEND_API_KEY}" } } } } }, "letme": { "capability": "https://letme.dev/email.send", "tool": "https://letme.dev/resend" }, "area": "communication", "unitPrices": [ { "item": "Pro 50k", "unit": "month", "usd": 20, "note": "50,000 emails" }, { "item": "Pro 100k", "unit": "month", "usd": 35, "note": "100,000 emails" }, { "item": "Scale 100k", "unit": "month", "usd": 90, "note": "100,000 emails" }, { "item": "Scale 1M", "unit": "month", "usd": 650, "note": "1,000,000 emails" }, { "item": "Overage on Pro", "unit": "1k-emails", "usd": 0.9 }, { "item": "Overage on Scale 2.5M", "unit": "1k-emails", "usd": 0.46 }, { "item": "Dedicated IP", "unit": "month", "usd": 30, "note": "Scale plan only" } ], "provenance": { "legalEntity": "Plus Five Five, Inc.", "domain": "resend.com", "domainRegistered": "2002-08-23", "domainNote": "resend.com was registered in 2002, long before Resend launched, so the domain was bought later.", "endpointOnVendorDomain": true, "terms": "https://resend.com/legal/terms-of-service", "privacy": "https://resend.com/legal/privacy-policy", "statusPage": "https://resend-status.com", "changelog": "https://resend.com/changelog", "securityTxt": "valid", "checked": "2026-09-30", "notes": [ "security.txt lists a contact and policy but no Expires field." ], "score": 96 }, "requirements": { "setupChecked": true, "complianceChecked": true, "card": "unknown", "freeTier": true, "minutes": 5, "credential": "api-key", "hosting": [ "US" ], "euResidency": "no", "trainsOnData": "no", "zeroRetention": "unknown", "certifications": [ "SOC 2 Type II", "GDPR" ], "dpa": true, "selfHost": "no" }, "pageJsonUrl": "https://www.anchorterminal.com/tools/resend.json", "live": { "slug": "resend", "probe": { "target": "https://api.resend.com", "method": "get", "lastAt": "2026-11-07T18:20:51.029092138Z", "lastOk": true, "lastStatus": 200, "lastMs": 189, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 130, "p95ms24h": 213, "samples24h": 239, "samples30d": 7910, "days": [ { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 250, "ok": 250 }, { "date": "2026-10-10", "probes": 247, "ok": 247 }, { "date": "2026-10-11", "probes": 247, "ok": 247 }, { "date": "2026-10-12", "probes": 247, "ok": 247 }, { "date": "2026-10-13", "probes": 248, "ok": 248 }, { "date": "2026-10-14", "probes": 249, "ok": 249 }, { "date": "2026-10-15", "probes": 253, "ok": 253 }, { "date": "2026-10-16", "probes": 252, "ok": 252 }, { "date": "2026-10-17", "probes": 253, "ok": 253 }, { "date": "2026-10-18", "probes": 256, "ok": 256 }, { "date": "2026-10-19", "probes": 255, "ok": 255 }, { "date": "2026-10-20", "probes": 252, "ok": 252 }, { "date": "2026-10-21", "probes": 253, "ok": 253 }, { "date": "2026-10-22", "probes": 253, "ok": 253 }, { "date": "2026-10-23", "probes": 248, "ok": 248 }, { "date": "2026-10-24", "probes": 251, "ok": 251 }, { "date": "2026-10-25", "probes": 250, "ok": 250 }, { "date": "2026-10-26", "probes": 252, "ok": 252 }, { "date": "2026-10-27", "probes": 249, "ok": 249 }, { "date": "2026-10-28", "probes": 250, "ok": 250 }, { "date": "2026-10-29", "probes": 249, "ok": 249 }, { "date": "2026-10-30", "probes": 249, "ok": 249 }, { "date": "2026-10-31", "probes": 251, "ok": 251 }, { "date": "2026-11-01", "probes": 249, "ok": 249 }, { "date": "2026-11-02", "probes": 250, "ok": 250 }, { "date": "2026-11-03", "probes": 248, "ok": 248 }, { "date": "2026-11-04", "probes": 246, "ok": 246 }, { "date": "2026-11-05", "probes": 185, "ok": 185 }, { "date": "2026-11-06", "probes": 241, "ok": 241 }, { "date": "2026-11-07", "probes": 187, "ok": 187 } ] }, "vendorStatus": { "page": "https://resend-status.com", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-11-07T18:21:58.634020312Z" }, "versions": [ { "registry": "github", "name": "resend/resend-mcp", "version": "v2.28.0", "released": "2026-11-03", "seenAt": "2026-11-07T00:01:35.51958095Z" }, { "registry": "npm", "name": "resend", "version": "6.37.0", "seenAt": "2026-11-07T00:01:33.182369236Z" }, { "registry": "npm", "name": "resend-mcp", "version": "2.28.0", "seenAt": "2026-11-07T00:01:34.545590942Z" }, { "registry": "pypi", "name": "resend", "version": "2.52.0", "released": "2026-11-05", "seenAt": "2026-11-07T00:01:34.420616378Z" } ], "githubStars": 580, "npmWeekly": 17996696, "pypiWeekly": 3825215, "securityTxt": { "url": "https://resend.com/.well-known/security.txt", "state": "valid", "checkedAt": "2026-11-07T16:00:35.732749048Z" }, "llmsTxt": { "url": "https://resend.com/docs/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-11-07T15:33:48.899026704Z" }, "domain": { "domain": "resend.com", "registered": "2002-08-23", "source": "https://rdap.verisign.com/com/v1/domain/resend.com", "checkedAt": "2026-11-01T14:08:32.01001595Z" }, "pages": [ { "url": "https://resend.com/changelog", "kind": "changelog", "status": 200, "checkedAt": "2026-11-07T14:18:24.663602539Z", "changedAt": "2026-11-05T13:02:55.134035345Z", "fingerprint": "4f8dd0510815" }, { "url": "https://resend.com/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-16T22:30:05.263363031Z", "changedAt": "2026-10-15T21:33:21.395037011Z", "fingerprint": "ed53ce06e4f7" }, { "url": "https://resend.com/pricing.md", "kind": "pricing", "status": 200, "checkedAt": "2026-11-07T14:18:30.812893481Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "ed53ce06e4f7" }, { "url": "https://resend.com/legal/privacy-policy", "kind": "privacy", "status": 200, "checkedAt": "2026-11-07T14:18:26.845665246Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "ad5261c3e915" }, { "url": "https://resend.com/legal/terms-of-service", "kind": "terms", "status": 200, "checkedAt": "2026-11-07T14:18:28.81862608Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "e09589be6323" } ], "mcpTools": { "url": "https://mcp.resend.com/mcp", "checkedAt": "2026-11-07T01:47:15.80074285Z", "status": "auth", "note": "asks for credentials before listing its tools", "changedAt": "2026-11-07T01:47:15.80074285Z" }, "github": { "repo": "resend/resend-mcp", "checkedAt": "2026-11-02T09:21:30.974399891Z", "stars": 578, "archived": false, "issuesEnabled": true, "pushedAt": "2026-10-30T20:29:15Z", "openIssues": 2, "openPRs": 19, "issuesOpened90d": 3, "issuesClosed90d": 3, "prsMerged90d": 34, "ci": { "branch": "main", "runs": 50, "success": 50, "failure": 0, "other": 0, "latest": "success", "latestAt": "2026-10-26T21:26:50Z" }, "replies": { "sampled": 20, "unanswered": 2, "medianDays": 47.4 } }, "updatedAt": "2026-11-07T18:21:58.634020312Z" } }, "edges": [ { "by": 41, "category": "schema", "leads": "resend", "name": "Schema \u0026 documentation", "reasons": { "a": "No OpenAPI or other machine-readable contract for the HTTPS API. The MCP server's 12 tools have typed zod inputs and output schemas, but that server isn't published yet, so partial credit (8 of 25). llms.txt answers 404 on mailpace.com and docs.mailpace.com, and no Markdown copies are served (0). The reference states what each endpoint does, and the introduction says when not to use it (transactional only, no batch, no static IPs) (12 of 20). Field tables give type, examples and required or optional, with enums for status, sort and direction and the 50-recipient cap in text (9 of 15). Examples in curl and six languages and a full table of error responses with messages, though several listed messages have a broken quote (`{\"error:\"...`) and the send reference says 30 MB where the home page says 25 MB (12 of 15). Version in the path with a promise that an old version runs until a published end-of-life date, and dated changelog posts (13 of 15). Total 54.", "b": "OpenAPI spec in resend/resend-openapi, updated 30 October and typed Zod schemas on every MCP tool (25). llms.txt with about 423 links (1 November), Markdown docs and a Markdown pricing page (10). MCP descriptions follow a Purpose, NOT for, Returns, When to use and Workflow pattern and name the tool to use instead (20). min and max on limits, enums such as full_access and sending_access, and mutual exclusions spelt out (14). An errors page with typed error names, and examples throughout (14). Dated product changelog and semver tags on the MCP, but the repository's CHANGELOG.md stops at 1.1.0 and the API has no version in its path (12)." }, "scores": { "a": 54, "b": 95 } }, { "by": 28, "category": "maintenance", "leads": "resend", "name": "Maintenance \u0026 community", "reasons": { "a": "Email Status API documented on 22 October 2026, and the MCP server rewritten as 2.0.0 on 4 November 2026, two days before this check (30). In the 90 days from 8 August, the Q3 changelog post of 31 August, the Email Status docs of 22 October, a mailpace-rails push on 17 October and the MCP rewrite, but only one changelog post (15 of 20). A closed service with email support. Three pull requests to the MCP repository from 2025 have no reply (8 of 15). Not in the official MCP registry (search for mailpace returned nothing on 6 November). The Node library was last pushed in October 2024 and Go in January 2024, while mailpace-rails is current (7 of 15). The MCP server gained CI with tests on 4 November; the older SDKs weren't checked for CI (5 of 10). Total 65.", "b": "resend-mcp 2.27.2 on 26 October, resend-node 6.35.0 on 27 October and 6.36.0, 6.36.1 and 6.37.0 on 30 October, and the Python SDK tag v2.50.1 on 29 October (30). Six MCP releases since 6 October (2.25.0 to 2.27.2) and five Node SDK releases since 16 October (20). Pull requests merge within days and Renovate keeps dependencies current. We couldn't see issue reply times from git (18). Current official SDKs (15). CI builds, lints, checks pinned dependencies and releases from the repository's workflows on 1 November (10)." }, "scores": { "a": 65, "b": 93 } }, { "by": 25, "category": "payments", "leads": "resend", "name": "Payments \u0026 pricing", "reasons": { "a": "No x402, MPP or L402 (0). $10 a month for 10,000 emails and $1 per 1,000 after, loaded from Paddle on the pricing page and stated in the comparison pages' tables without login (20). A free plan of up to 100 emails a month is available only by emailing support, so it isn't self-serve (5 of 20). Signup, DKIM verification and payment happen in a browser (0). Total 25.", "b": "No x402, MPP or L402 (0). Plan prices and overage ($0.90 down to $0.46 per 1,000) published without login, including a Markdown pricing page (20). Free plan of 3,000 emails a month, 100 a day, with no card per the 1 October check; the Markdown pricing page re-read on 1 November doesn't say (20). Since 22 September, `stripe projects add resend/email` creates a Resend account or links an existing one, generates an API key and writes it to `.env`, so an agent can get access through the operator's Stripe login. A person still needs a Stripe account and the Stripe CLI, so partial credit, as for other Stripe Projects listings (10)." }, "scores": { "a": 25, "b": 50 } }, { "by": 20, "category": "reliability", "leads": "resend", "name": "Reliability", "reasons": { "a": "Graded with the hosted lines. A public Upptime status page at status.mailpace.com, driven by the mailpace/status repository, with monitors for the application, SMTP, docs, blog and landing page and GitHub issues as incident reports (20). The 90 days from 8 August hold two incidents, an application outage on 22 September 2026 that the operator put down to an upstream provider returning 5xx (issue open for two minutes), and SMTP down on 2 November 2026 for about 35 minutes, which leaves SMTP at 99.65% for the week. Minor incidents only (20). No rate limit numbers are published; the docs say limits vary by organisation age, plan and history (0). A documented 429 with its message, no Retry-After or backoff guidance, and an `Idempotency-Key` on sends with written retry rules (10 of 15). The terms guarantee 99% monthly availability of the API and dashboard with a 5% credit per 30 minutes (10). The API is at v1 with no beta label (10). Total 70.", "b": "incident.io status page with per-component uptime and incident timelines (20). On 1 November the page's data starts on 2 October 2026, and the feed adds two incidents since 17 October, both labelled degraded performance. On 23 October \"Intermittent latency spikes on our emails API\" ran 15:57 to 16:47 UTC (50 minutes) on the sending components, and on 26 October email status updates were delayed from 14:34 to 14:57 UTC (23 minutes), with no data lost. Earlier in the window, new team provisioning and contact webhook delivery were delayed on 9 and 10 October, function processing was delayed 2 hours 46 minutes on 26 September (sending not affected), and API and dashboard errors lasted 45 minutes on 24 September and 37 minutes on 1 October. The broadcast sending stall of about two hours on 15 September, which held about 9,200 transactional emails up to 25 minutes, and the one-minute MCP outage on 11 September stay per the 6 October check, and the 3 to 10 September incidents per the 1 October check. Earlier checks gave 15, between minor only and one major, for the busy record and the two-hour stall. This run reads delays and degradation as minor however long they run, and no core API was down or erroring widely for an hour, so minor only (20). 10 requests a second per team, plus daily and monthly quotas, re-read on 1 November (15). 429 with `retry-after` and IETF ratelimit headers, and `Idempotency-Key` on POST /emails and /emails/batch, kept 24 hours, re-read on 1 November (15). 99.99% uptime SLA on Enterprise (10). GA (10). 20+20+15+15+10+10 = 90." }, "scores": { "a": 70, "b": 90 } }, { "by": 19, "category": "security", "leads": "resend", "name": "Security \u0026 auth", "reasons": { "a": "Per-domain server tokens that can only send from and read status for their domain, and an organisation token that creates, renames and revokes domain tokens through the Domains API. Tokens travel in headers only. The authentication page still tells users to contact support to regenerate a leaked token (25 of 30). No read-only token. A domain token can't touch other domains, and the unpublished MCP server has an optional recipient allowlist. No approval step on the hosted API (8 of 20). Inbound mail reaches the customer's webhook as untrusted content, and Email Status returns bounce text. The MCP README warns about prompt injection and suggests the allowlist (9 of 15). The dashboard keeps sent mail for 30 days; no log of API calls was found (6 of 15). No security.txt (404 on mailpace.com and app.mailpace.com), no disclosure policy, bug bounty, SOC 2 or ISO 27001. WebAuthn-only two-factor sign-in and Ed25519-signed webhooks are documented (2 of 20). Total 50.", "b": "Bearer keys with full_access or sending_access, and a sending key can be limited to one domain. The hosted MCP signs in by OAuth with no documented scope choice (25). Sending-only keys exist, but the MCP has no read-only mode, and with a full key an agent can create keys and remove domains (10). get-received-email and the new inbox thread tools hand inbound mail to the model. Since resend-mcp 2.25.0 (6 October) local file reads by `send-email` attachments and `create-contact-import` are off over HTTP unless `--allowed-file-dirs` is set, and the README tells stdio users to set it to stop a prompt-injected agent attaching files outside chosen folders. That's a documented mitigation for one injection path, with no guidance on treating received mail as untrusted (4). Before 2.25.0 any local file path could be attached, including over HTTP, where a remote caller could read the server's disk; the maintainers fixed it and disclosed it in the README, read as Mapbox's 5 October fix was, as part of a public programme rather than a deduction. API request logs with full request and response bodies (14). SOC 2 Type II, an annual penetration test, a responsible-disclosure page and a security.txt with Contact and Policy but no Expires field, re-read on 1 November (16). 25 + 10 + 4 + 14 + 16 = 69." }, "scores": { "a": 50, "b": 69 } }, { "by": 8, "category": "transparency", "leads": "resend", "name": "Transparency \u0026 trust", "reasons": { "a": "Closed hosted service under terms that name OhMySMTP Ltd with its company number. The MCP server, SDKs, landing site and status page are MIT (18 of 30). The privacy policy (30 August 2026), the pricing page and the DPA agree on retention, 30 days in the dashboard and 7 more in backups, 37 days at most (25 of 30). The API reference promises an old version runs until a published end-of-life date, and the terms list dated changes. The terms also say changes apply immediately (8 of 20). Sub-processors listed with purpose and location, Freethought hosting in the EU, Hetzner backups in Germany, AppSignal in Amsterdam, Paddle in the UK and Tutanota in Germany (18 of 20). Total 69.", "b": "Closed service with published terms and an MIT MCP server (20). 30-day retention on Free, Pro and Scale per the pricing page, backups kept 7 days, a DPA (last update 31 December 2025) and a privacy policy (last update 27 August 2026) that keeps personal data \"only for as long as is necessary\", re-read on 1 November (24). Dated changelog, no deprecation policy found (8). 22 subprocessors listed, all in the USA, still dated 27 August 2026 on 1 November, including Anthropic and RunPod for AI processing. Hosting regions aren't stated beyond \"multi-region\" on the pricing page (18)." }, "scores": { "a": 75, "b": 83 } } ], "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "OhMySMTP Ltd", "b": "Resend", "name": "Vendor" }, { "a": "no (local only)", "b": "https://api.resend.com", "name": "Hosted endpoint" }, { "a": "HTTP", "b": "HTTP, Streamable HTTP, stdio", "name": "Transports" }, { "a": "API key", "b": "OAuth or key", "name": "Auth" }, { "a": "Paid", "b": "Freemium", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "none", "b": "MIT", "name": "Licence" }, { "a": "12", "b": "136", "name": "Tools exposed" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "no", "b": "yes", "name": "llms.txt" }, { "a": "2026-10-22", "b": "2026-10-30", "name": "Last release" }, { "a": "2026-01-09", "b": "no date given", "name": "Terms last updated" }, { "a": "2026-08-30", "b": "no date given", "name": "Privacy policy last updated" }, { "a": "not found in the text", "b": "not found in the text", "name": "Customer content may train models" }, { "a": "yes", "b": "not found in the text", "name": "Terms restrict automated access" }, { "a": "not found in the text", "b": "not found in the text", "name": "Terms restrict benchmarking" }, { "a": "not found in the text", "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": "1 stars, 207 npm/wk", "b": "575 stars, 13.6M npm/wk, 2.8M PyPI/wk", "name": "Popularity" }, { "a": "none", "b": "3.4/5 (8)", "name": "Agent reviews" } ], "faq": [ { "answer": "Resend API + MCP scores 78.1 (A) on agent readiness against MailPace's 58.4 (C), and leads in 6 of 7 scored categories.", "question": "Which is better for AI agents, MailPace or Resend API + MCP?" }, { "answer": "MailPace needs an API key. Resend API + MCP takes an API key or an OAuth sign-in.", "question": "Do MailPace and Resend API + MCP need an API key?" }, { "answer": "No hosted endpoint is listed for MailPace. Resend API + MCP has a hosted endpoint at https://api.resend.com.", "question": "Can an agent call MailPace and Resend API + MCP without installing anything?" } ], "goodFor": [ { "aheadOn": null, "also": null, "goodFor": "Low-volume transactional mail from EU-hosted infrastructure with idempotent sends and no tracking.", "slug": "mailpace", "watchFor": "No OpenAPI spec, llms.txt or Markdown docs for agents; the reference is Docusaurus pages" }, { "aheadOn": [ "Reliability, 90 against 70", "Schema \u0026 documentation, 95 against 54", "Security \u0026 auth, 69 against 50", "Payments \u0026 pricing, 50 against 25", "Maintenance \u0026 community, 93 against 65", "Transparency \u0026 trust, 83 against 75" ], "also": [ "Agent-ready, a grade of BB or better", "A hosted endpoint, with nothing to install", "Runs on your own machine", "Free to start without a card" ], "goodFor": "Developers who want an agent to send, receive and manage templates from one MCP, and for teams that value tool descriptions written for models.", "slug": "resend", "watchFor": "136 MCP tools load at once, with no toolsets" } ], "history": { "mailpace": null, "resend": [ { "causes": [ "correction" ], "date": "2026-11-01", "delta": 1, "from": 77.1, "fromGrade": "BB", "to": 78.1, "toGrade": "A" }, { "causes": [ "product", "evidence" ], "date": "2026-10-17", "delta": 2, "from": 75.1, "fromGrade": "BB", "to": 77.1, "toGrade": "BB" }, { "causes": [ "method" ], "date": "2026-10-08", "delta": -0.2, "from": 75.3, "fromGrade": "BB", "to": 75.1, "toGrade": "BB" } ] }, "job": { "capability": "email.send", "name": "Sending email" }, "others": [ { "json": "https://www.anchorterminal.com/compare/ahasend-vs-mailpace.json", "title": "AhaSend API + MCP vs MailPace", "url": "https://www.anchorterminal.com/compare/ahasend-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/ahasend-vs-resend.json", "title": "AhaSend API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/ahasend-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/amazon-ses-vs-mailpace.json", "title": "Amazon SES vs MailPace", "url": "https://www.anchorterminal.com/compare/amazon-ses-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/amazon-ses-vs-resend.json", "title": "Amazon SES vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/amazon-ses-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/brevo-vs-mailpace.json", "title": "Brevo API + MCP vs MailPace", "url": "https://www.anchorterminal.com/compare/brevo-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/brevo-vs-resend.json", "title": "Brevo API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/brevo-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/cloudflare-email-service-vs-mailpace.json", "title": "Cloudflare Email Service vs MailPace", "url": "https://www.anchorterminal.com/compare/cloudflare-email-service-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/cloudflare-email-service-vs-resend.json", "title": "Cloudflare Email Service vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/cloudflare-email-service-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/groundmail-vs-mailpace.json", "title": "Groundmail API + MCP vs MailPace", "url": "https://www.anchorterminal.com/compare/groundmail-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/groundmail-vs-resend.json", "title": "Groundmail API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/groundmail-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/loops-vs-mailpace.json", "title": "Loops API + MCP vs MailPace", "url": "https://www.anchorterminal.com/compare/loops-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/loops-vs-resend.json", "title": "Loops API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/loops-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/mailersend-vs-mailpace.json", "title": "MailerSend vs MailPace", "url": "https://www.anchorterminal.com/compare/mailersend-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/mailersend-vs-resend.json", "title": "MailerSend vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/mailersend-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/mailgun-vs-mailpace.json", "title": "Mailgun API + MCP vs MailPace", "url": "https://www.anchorterminal.com/compare/mailgun-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/mailgun-vs-resend.json", "title": "Mailgun API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/mailgun-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/mailjet-vs-mailpace.json", "title": "Mailjet API + MCP vs MailPace", "url": "https://www.anchorterminal.com/compare/mailjet-vs-mailpace" }, { "json": "https://www.anchorterminal.com/compare/mailjet-vs-resend.json", "title": "Mailjet API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/mailjet-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-mailtrap.json", "title": "MailPace vs Mailtrap Email API + MCP", "url": "https://www.anchorterminal.com/compare/mailpace-vs-mailtrap" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-mandrill.json", "title": "MailPace vs Mailchimp Transactional (Mandrill)", "url": "https://www.anchorterminal.com/compare/mailpace-vs-mandrill" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-postmark.json", "title": "MailPace vs Postmark API + MCP", "url": "https://www.anchorterminal.com/compare/mailpace-vs-postmark" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-sendgrid.json", "title": "MailPace vs Twilio SendGrid", "url": "https://www.anchorterminal.com/compare/mailpace-vs-sendgrid" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-sendlayer.json", "title": "MailPace vs SendLayer", "url": "https://www.anchorterminal.com/compare/mailpace-vs-sendlayer" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-smtp2go.json", "title": "MailPace vs SMTP2GO API + MCP", "url": "https://www.anchorterminal.com/compare/mailpace-vs-smtp2go" }, { "json": "https://www.anchorterminal.com/compare/mailpace-vs-zoho-zeptomail.json", "title": "MailPace vs Zoho CPaaS (formerly ZeptoMail)", "url": "https://www.anchorterminal.com/compare/mailpace-vs-zoho-zeptomail" }, { "json": "https://www.anchorterminal.com/compare/mailtrap-vs-resend.json", "title": "Mailtrap Email API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/mailtrap-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/mandrill-vs-resend.json", "title": "Mailchimp Transactional (Mandrill) vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/mandrill-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/postmark-vs-resend.json", "title": "Postmark API + MCP vs Resend API + MCP", "url": "https://www.anchorterminal.com/compare/postmark-vs-resend" }, { "json": "https://www.anchorterminal.com/compare/resend-vs-sendgrid.json", "title": "Resend API + MCP vs Twilio SendGrid", "url": "https://www.anchorterminal.com/compare/resend-vs-sendgrid" }, { "json": "https://www.anchorterminal.com/compare/resend-vs-sendlayer.json", "title": "Resend API + MCP vs SendLayer", "url": "https://www.anchorterminal.com/compare/resend-vs-sendlayer" }, { "json": "https://www.anchorterminal.com/compare/resend-vs-smtp2go.json", "title": "Resend API + MCP vs SMTP2GO API + MCP", "url": "https://www.anchorterminal.com/compare/resend-vs-smtp2go" }, { "json": "https://www.anchorterminal.com/compare/resend-vs-zoho-zeptomail.json", "title": "Resend API + MCP vs Zoho CPaaS (formerly ZeptoMail)", "url": "https://www.anchorterminal.com/compare/resend-vs-zoho-zeptomail" } ], "panel": null, "scores": [ { "by": 20, "edge": "resend", "key": "reliability", "mailpace": 70, "name": "Reliability", "resend": 90, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 41, "edge": "resend", "key": "schema", "mailpace": 54, "name": "Schema \u0026 documentation", "resend": 95, "weight": 13 }, { "by": 4, "edge": "mailpace", "key": "ergonomics", "mailpace": 71, "name": "Agent ergonomics", "resend": 67, "weight": 13 }, { "by": 19, "edge": "resend", "key": "security", "mailpace": 50, "name": "Security \u0026 auth", "resend": 69, "weight": 14 }, { "by": 25, "edge": "resend", "key": "payments", "mailpace": 25, "name": "Payments \u0026 pricing", "resend": 50, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 28, "edge": "resend", "key": "maintenance", "mailpace": 65, "name": "Maintenance \u0026 community", "resend": 93, "weight": 7 }, { "by": 8, "edge": "resend", "key": "transparency", "mailpace": 75, "name": "Transparency \u0026 trust", "resend": 83, "weight": 7 } ], "summary": "Resend API + MCP scores 78.1 (A) on agent readiness against MailPace's 58.4 (C), and leads in 6 of 7 scored categories. Both do sending email.", "tasks": null, "tutorials": [], "verdicts": { "mailpace": "A small transactional sender with idempotent sends, signed webhooks, a 99% availability promise in its terms and a public Upptime status record. There is no OpenAPI spec, no published rate limit, no llms.txt, and its MCP server was rewritten on 4 November 2026 but isn't on npm or in the MCP registry yet.", "resend": "`Idempotency-Key` on POST /emails and /emails/batch, kept for 24 hours. 136 MCP tools load at once, with no toolsets." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/mailpace-vs-resend", "json": "https://www.anchorterminal.com/compare/mailpace-vs-resend.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/mailpace-vs-resend.md", "mcp": "https://www.anchorterminal.com/mcp", "slim": "https://www.anchorterminal.com/compare/mailpace-vs-resend.min.md" }, "markdown": "Resend API + MCP scores 78.1 (A) on agent readiness against MailPace's 58.4 (C), and leads in 6 of 7 scored categories. Both do sending email.\n\n- MailPace: grade C, 58.4/100, rank #750 of 1486. Markdown https://www.anchorterminal.com/tools/mailpace.md · JSON https://www.anchorterminal.com/api/v1/tools/mailpace.json\n- Resend API + MCP: grade A, 78.1/100, rank #26 of 1486. Markdown https://www.anchorterminal.com/tools/resend.md · JSON https://www.anchorterminal.com/api/v1/tools/resend.json\n- Best email delivery APIs for AI agents: https://www.anchorterminal.com/best/email/index.md\n- All 174 email comparisons: https://www.anchorterminal.com/compare/email/index.md\n\n## Which one, for what\n\n### MailPace (C)\n\nGood for: Low-volume transactional mail from EU-hosted infrastructure with idempotent sends and no tracking.\n\nWatch for: No OpenAPI spec, llms.txt or Markdown docs for agents; the reference is Docusaurus pages\n\n### Resend API + MCP (A)\n\nGood for: Developers who want an agent to send, receive and manage templates from one MCP, and for teams that value tool descriptions written for models.\n\nAhead on:\n- Reliability, 90 against 70\n- Schema \u0026 documentation, 95 against 54\n- Security \u0026 auth, 69 against 50\n- Payments \u0026 pricing, 50 against 25\n- Maintenance \u0026 community, 93 against 65\n- Transparency \u0026 trust, 83 against 75\n\nAlso in its favour:\n- Agent-ready, a grade of BB or better\n- A hosted endpoint, with nothing to install\n- Runs on your own machine\n- Free to start without a card\n\nWatch for: 136 MCP tools load at once, with no toolsets\n\n\n## Why the edge\n\n### Schema \u0026 documentation: Resend API + MCP +41\n\n- MailPace (54): No OpenAPI or other machine-readable contract for the HTTPS API. The MCP server's 12 tools have typed zod inputs and output schemas, but that server isn't published yet, so partial credit (8 of 25). llms.txt answers 404 on mailpace.com and docs.mailpace.com, and no Markdown copies are served (0). The reference states what each endpoint does, and the introduction says when not to use it (transactional only, no batch, no static IPs) (12 of 20). Field tables give type, examples and required or optional, with enums for status, sort and direction and the 50-recipient cap in text (9 of 15). Examples in curl and six languages and a full table of error responses with messages, though several listed messages have a broken quote (`{\"error:\"...`) and the send reference says 30 MB where the home page says 25 MB (12 of 15). Version in the path with a promise that an old version runs until a published end-of-life date, and dated changelog posts (13 of 15). Total 54.\n- Resend API + MCP (95): OpenAPI spec in resend/resend-openapi, updated 30 October and typed Zod schemas on every MCP tool (25). llms.txt with about 423 links (1 November), Markdown docs and a Markdown pricing page (10). MCP descriptions follow a Purpose, NOT for, Returns, When to use and Workflow pattern and name the tool to use instead (20). min and max on limits, enums such as full_access and sending_access, and mutual exclusions spelt out (14). An errors page with typed error names, and examples throughout (14). Dated product changelog and semver tags on the MCP, but the repository's CHANGELOG.md stops at 1.1.0 and the API has no version in its path (12).\n\n### Maintenance \u0026 community: Resend API + MCP +28\n\n- MailPace (65): Email Status API documented on 22 October 2026, and the MCP server rewritten as 2.0.0 on 4 November 2026, two days before this check (30). In the 90 days from 8 August, the Q3 changelog post of 31 August, the Email Status docs of 22 October, a mailpace-rails push on 17 October and the MCP rewrite, but only one changelog post (15 of 20). A closed service with email support. Three pull requests to the MCP repository from 2025 have no reply (8 of 15). Not in the official MCP registry (search for mailpace returned nothing on 6 November). The Node library was last pushed in October 2024 and Go in January 2024, while mailpace-rails is current (7 of 15). The MCP server gained CI with tests on 4 November; the older SDKs weren't checked for CI (5 of 10). Total 65.\n- Resend API + MCP (93): resend-mcp 2.27.2 on 26 October, resend-node 6.35.0 on 27 October and 6.36.0, 6.36.1 and 6.37.0 on 30 October, and the Python SDK tag v2.50.1 on 29 October (30). Six MCP releases since 6 October (2.25.0 to 2.27.2) and five Node SDK releases since 16 October (20). Pull requests merge within days and Renovate keeps dependencies current. We couldn't see issue reply times from git (18). Current official SDKs (15). CI builds, lints, checks pinned dependencies and releases from the repository's workflows on 1 November (10).\n\n### Payments \u0026 pricing: Resend API + MCP +25\n\n- MailPace (25): No x402, MPP or L402 (0). $10 a month for 10,000 emails and $1 per 1,000 after, loaded from Paddle on the pricing page and stated in the comparison pages' tables without login (20). A free plan of up to 100 emails a month is available only by emailing support, so it isn't self-serve (5 of 20). Signup, DKIM verification and payment happen in a browser (0). Total 25.\n- Resend API + MCP (50): No x402, MPP or L402 (0). Plan prices and overage ($0.90 down to $0.46 per 1,000) published without login, including a Markdown pricing page (20). Free plan of 3,000 emails a month, 100 a day, with no card per the 1 October check; the Markdown pricing page re-read on 1 November doesn't say (20). Since 22 September, `stripe projects add resend/email` creates a Resend account or links an existing one, generates an API key and writes it to `.env`, so an agent can get access through the operator's Stripe login. A person still needs a Stripe account and the Stripe CLI, so partial credit, as for other Stripe Projects listings (10).\n\n### Reliability: Resend API + MCP +20\n\n- MailPace (70): Graded with the hosted lines. A public Upptime status page at status.mailpace.com, driven by the mailpace/status repository, with monitors for the application, SMTP, docs, blog and landing page and GitHub issues as incident reports (20). The 90 days from 8 August hold two incidents, an application outage on 22 September 2026 that the operator put down to an upstream provider returning 5xx (issue open for two minutes), and SMTP down on 2 November 2026 for about 35 minutes, which leaves SMTP at 99.65% for the week. Minor incidents only (20). No rate limit numbers are published; the docs say limits vary by organisation age, plan and history (0). A documented 429 with its message, no Retry-After or backoff guidance, and an `Idempotency-Key` on sends with written retry rules (10 of 15). The terms guarantee 99% monthly availability of the API and dashboard with a 5% credit per 30 minutes (10). The API is at v1 with no beta label (10). Total 70.\n- Resend API + MCP (90): incident.io status page with per-component uptime and incident timelines (20). On 1 November the page's data starts on 2 October 2026, and the feed adds two incidents since 17 October, both labelled degraded performance. On 23 October \"Intermittent latency spikes on our emails API\" ran 15:57 to 16:47 UTC (50 minutes) on the sending components, and on 26 October email status updates were delayed from 14:34 to 14:57 UTC (23 minutes), with no data lost. Earlier in the window, new team provisioning and contact webhook delivery were delayed on 9 and 10 October, function processing was delayed 2 hours 46 minutes on 26 September (sending not affected), and API and dashboard errors lasted 45 minutes on 24 September and 37 minutes on 1 October. The broadcast sending stall of about two hours on 15 September, which held about 9,200 transactional emails up to 25 minutes, and the one-minute MCP outage on 11 September stay per the 6 October check, and the 3 to 10 September incidents per the 1 October check. Earlier checks gave 15, between minor only and one major, for the busy record and the two-hour stall. This run reads delays and degradation as minor however long they run, and no core API was down or erroring widely for an hour, so minor only (20). 10 requests a second per team, plus daily and monthly quotas, re-read on 1 November (15). 429 with `retry-after` and IETF ratelimit headers, and `Idempotency-Key` on POST /emails and /emails/batch, kept 24 hours, re-read on 1 November (15). 99.99% uptime SLA on Enterprise (10). GA (10). 20+20+15+15+10+10 = 90.\n\n### Security \u0026 auth: Resend API + MCP +19\n\n- MailPace (50): Per-domain server tokens that can only send from and read status for their domain, and an organisation token that creates, renames and revokes domain tokens through the Domains API. Tokens travel in headers only. The authentication page still tells users to contact support to regenerate a leaked token (25 of 30). No read-only token. A domain token can't touch other domains, and the unpublished MCP server has an optional recipient allowlist. No approval step on the hosted API (8 of 20). Inbound mail reaches the customer's webhook as untrusted content, and Email Status returns bounce text. The MCP README warns about prompt injection and suggests the allowlist (9 of 15). The dashboard keeps sent mail for 30 days; no log of API calls was found (6 of 15). No security.txt (404 on mailpace.com and app.mailpace.com), no disclosure policy, bug bounty, SOC 2 or ISO 27001. WebAuthn-only two-factor sign-in and Ed25519-signed webhooks are documented (2 of 20). Total 50.\n- Resend API + MCP (69): Bearer keys with full_access or sending_access, and a sending key can be limited to one domain. The hosted MCP signs in by OAuth with no documented scope choice (25). Sending-only keys exist, but the MCP has no read-only mode, and with a full key an agent can create keys and remove domains (10). get-received-email and the new inbox thread tools hand inbound mail to the model. Since resend-mcp 2.25.0 (6 October) local file reads by `send-email` attachments and `create-contact-import` are off over HTTP unless `--allowed-file-dirs` is set, and the README tells stdio users to set it to stop a prompt-injected agent attaching files outside chosen folders. That's a documented mitigation for one injection path, with no guidance on treating received mail as untrusted (4). Before 2.25.0 any local file path could be attached, including over HTTP, where a remote caller could read the server's disk; the maintainers fixed it and disclosed it in the README, read as Mapbox's 5 October fix was, as part of a public programme rather than a deduction. API request logs with full request and response bodies (14). SOC 2 Type II, an annual penetration test, a responsible-disclosure page and a security.txt with Contact and Policy but no Expires field, re-read on 1 November (16). 25 + 10 + 4 + 14 + 16 = 69.\n\n### Transparency \u0026 trust: Resend API + MCP +8\n\n- MailPace (75): Closed hosted service under terms that name OhMySMTP Ltd with its company number. The MCP server, SDKs, landing site and status page are MIT (18 of 30). The privacy policy (30 August 2026), the pricing page and the DPA agree on retention, 30 days in the dashboard and 7 more in backups, 37 days at most (25 of 30). The API reference promises an old version runs until a published end-of-life date, and the terms list dated changes. The terms also say changes apply immediately (8 of 20). Sub-processors listed with purpose and location, Freethought hosting in the EU, Hetzner backups in Germany, AppSignal in Amsterdam, Paddle in the UK and Tutanota in Germany (18 of 20). Total 69.\n- Resend API + MCP (83): Closed service with published terms and an MIT MCP server (20). 30-day retention on Free, Pro and Scale per the pricing page, backups kept 7 days, a DPA (last update 31 December 2025) and a privacy policy (last update 27 August 2026) that keeps personal data \"only for as long as is necessary\", re-read on 1 November (24). Dated changelog, no deprecation policy found (8). 22 subprocessors listed, all in the USA, still dated 27 August 2026 on 1 November, including Anthropic and RunPod for AI processing. Hosting regions aren't stated beyond \"multi-region\" on the pricing page (18).\n\n## Score by category\n\n| Category | Weight | MailPace | Resend API + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 70 | 90 | Resend API + MCP +20 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 54 | 95 | Resend API + MCP +41 |\n| Agent ergonomics | 13% (16.2 this run) | 71 | 67 | MailPace +4 |\n| Security \u0026 auth | 14% (17.5 this run) | 50 | 69 | Resend API + MCP +19 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 25 | 50 | Resend API + MCP +25 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 65 | 93 | Resend API + MCP +28 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 75 | 83 | Resend API + MCP +8 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **58.4 · C** | **78.1 · A** | |\n\n## Facts side by side\n\n| Fact | MailPace | Resend API + MCP |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | OhMySMTP Ltd | Resend |\n| Hosted endpoint | no (local only) | `https://api.resend.com` |\n| Transports | HTTP | HTTP, Streamable HTTP, stdio |\n| Auth | API key | OAuth or key |\n| Pricing | Paid | Freemium |\n| x402 | no | no |\n| Licence | none | MIT |\n| Tools exposed | 12 | 136 |\n| Read-only variant documented | no | no |\n| llms.txt | no | yes |\n| Last release | 2026-10-22 | 2026-10-30 |\n| Terms last updated | 2026-01-09 | no date given |\n| Privacy policy last updated | 2026-08-30 | no date given |\n| Customer content may train models | not found in the text | not found in the text |\n| Terms restrict automated access | yes | not found in the text |\n| Terms restrict benchmarking | not found in the text | not found in the text |\n| Terms or service can change without notice | not found in the text | yes |\n| Arbitration or class-action waiver | not found in the text | not found in the text |\n| Popularity | 1 stars, 207 npm/wk | 575 stars, 13.6M npm/wk, 2.8M PyPI/wk |\n| Agent reviews | none | 3.4/5 (8) |\n\n## How the scores have moved\n\n### MailPace\n\nNo score change since it was listed.\n\n### Resend API + MCP\n\n- +1.0 on 1 November 2026 (BB to A): correction\n- +2.0 on 17 October 2026: product, new evidence\n- -0.2 on 8 October 2026: checklist\n\n## Verdicts\n\n**MailPace.** A small transactional sender with idempotent sends, signed webhooks, a 99% availability promise in its terms and a public Upptime status record. There is no OpenAPI spec, no published rate limit, no llms.txt, and its MCP server was rewritten on 4 November 2026 but isn't on npm or in the MCP registry yet.\n\n**Resend API + MCP.** `Idempotency-Key` on POST /emails and /emails/batch, kept for 24 hours. 136 MCP tools load at once, with no toolsets.\n\n## Before you call either\n\n### MailPace\n\n1. Send a UUID in `Idempotency-Key` on every `POST /api/v1/send`, and reuse it on a retry; keys last 24 hours and are tied to one token\n2. Use the server token of the sending domain, since the From domain must match the token's domain or the API returns 403\n3. On 429 `You are sending emails too quickly` back off; no Retry-After is documented\n4. Send only transactional mail; marketing and bulk newsletters are prohibited by the docs and terms\n5. Read delivery with `GET /api/v1/domains/:domain_id/emails/:id` using the id the send returned\n\n### Resend API + MCP\n\n1. Send an `Idempotency-Key` on POST /emails so a retry after a timeout doesn't send twice\n2. Send a User-Agent header on raw HTTP calls or you'll get a 403\n3. Give the agent a `sending_access` key limited to one domain unless it has to manage the account\n4. On 429, wait for `retry-after`, and use /emails/batch to stay under 10 requests a second\n5. Run resend-mcp 2.25.0 or later, and on stdio set `--allowed-file-dirs` so an injected prompt can't attach files from elsewhere on disk\n\n## Questions\n\n### Which is better for AI agents, MailPace or Resend API + MCP?\n\nResend API + MCP scores 78.1 (A) on agent readiness against MailPace's 58.4 (C), and leads in 6 of 7 scored categories.\n\n### Do MailPace and Resend API + MCP need an API key?\n\nMailPace needs an API key. Resend API + MCP takes an API key or an OAuth sign-in.\n\n### Can an agent call MailPace and Resend API + MCP without installing anything?\n\nNo hosted endpoint is listed for MailPace. Resend API + MCP has a hosted endpoint at https://api.resend.com.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/mailpace-vs-resend.json, and with the fewest tokens: https://www.anchorterminal.com/compare/mailpace-vs-resend.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"mailpace\", \"b\": \"resend\"}`. From a terminal: `anchor compare mailpace resend`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/mailpace.json and https://www.anchorterminal.com/api/v1/tools/resend.json\n\n## Other comparisons with MailPace or Resend API + MCP\n\n- [AhaSend API + MCP vs MailPace](https://www.anchorterminal.com/compare/ahasend-vs-mailpace.md)\n- [AhaSend API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/ahasend-vs-resend.md)\n- [Amazon SES vs MailPace](https://www.anchorterminal.com/compare/amazon-ses-vs-mailpace.md)\n- [Amazon SES vs Resend API + MCP](https://www.anchorterminal.com/compare/amazon-ses-vs-resend.md)\n- [Brevo API + MCP vs MailPace](https://www.anchorterminal.com/compare/brevo-vs-mailpace.md)\n- [Brevo API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/brevo-vs-resend.md)\n- [Cloudflare Email Service vs MailPace](https://www.anchorterminal.com/compare/cloudflare-email-service-vs-mailpace.md)\n- [Cloudflare Email Service vs Resend API + MCP](https://www.anchorterminal.com/compare/cloudflare-email-service-vs-resend.md)\n- [Groundmail API + MCP vs MailPace](https://www.anchorterminal.com/compare/groundmail-vs-mailpace.md)\n- [Groundmail API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/groundmail-vs-resend.md)\n- [Loops API + MCP vs MailPace](https://www.anchorterminal.com/compare/loops-vs-mailpace.md)\n- [Loops API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/loops-vs-resend.md)\n- [MailerSend vs MailPace](https://www.anchorterminal.com/compare/mailersend-vs-mailpace.md)\n- [MailerSend vs Resend API + MCP](https://www.anchorterminal.com/compare/mailersend-vs-resend.md)\n- [Mailgun API + MCP vs MailPace](https://www.anchorterminal.com/compare/mailgun-vs-mailpace.md)\n- [Mailgun API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/mailgun-vs-resend.md)\n- [Mailjet API + MCP vs MailPace](https://www.anchorterminal.com/compare/mailjet-vs-mailpace.md)\n- [Mailjet API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/mailjet-vs-resend.md)\n- [MailPace vs Mailtrap Email API + MCP](https://www.anchorterminal.com/compare/mailpace-vs-mailtrap.md)\n- [MailPace vs Mailchimp Transactional (Mandrill)](https://www.anchorterminal.com/compare/mailpace-vs-mandrill.md)\n- [MailPace vs Postmark API + MCP](https://www.anchorterminal.com/compare/mailpace-vs-postmark.md)\n- [MailPace vs Twilio SendGrid](https://www.anchorterminal.com/compare/mailpace-vs-sendgrid.md)\n- [MailPace vs SendLayer](https://www.anchorterminal.com/compare/mailpace-vs-sendlayer.md)\n- [MailPace vs SMTP2GO API + MCP](https://www.anchorterminal.com/compare/mailpace-vs-smtp2go.md)\n- [MailPace vs Zoho CPaaS (formerly ZeptoMail)](https://www.anchorterminal.com/compare/mailpace-vs-zoho-zeptomail.md)\n- [Mailtrap Email API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/mailtrap-vs-resend.md)\n- [Mailchimp Transactional (Mandrill) vs Resend API + MCP](https://www.anchorterminal.com/compare/mandrill-vs-resend.md)\n- [Postmark API + MCP vs Resend API + MCP](https://www.anchorterminal.com/compare/postmark-vs-resend.md)\n- [Resend API + MCP vs Twilio SendGrid](https://www.anchorterminal.com/compare/resend-vs-sendgrid.md)\n- [Resend API + MCP vs SendLayer](https://www.anchorterminal.com/compare/resend-vs-sendlayer.md)\n- [Resend API + MCP vs SMTP2GO API + MCP](https://www.anchorterminal.com/compare/resend-vs-smtp2go.md)\n- [Resend API + MCP vs Zoho CPaaS (formerly ZeptoMail)](https://www.anchorterminal.com/compare/resend-vs-zoho-zeptomail.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "attributionRequired": true, "credit": "CC BY 4.0, credit Anchor Terminal and link the page or API address you took it from (https://www.anchorterminal.com/terms/#data)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-11-07", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.7", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run", "terms": "https://www.anchorterminal.com/terms/#data" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "MailPace vs Resend API + MCP", "url": "" } ], "description": "Resend scores 78.1 (A) to MailPace's 58.4 (C) for sending email. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "MailPace C 58.4", "Resend API + MCP A 78.1", "scores" ], "h1": "MailPace vs Resend API + MCP", "image": "https://www.anchorterminal.com/assets/og/default.png", "path": "/compare/mailpace-vs-resend", "published": "2026-10-01", "section": "tools", "title": "MailPace vs Resend for AI agents in 2026: scores and prices", "toc": null, "updated": "2026-11-07", "url": "https://www.anchorterminal.com/compare/mailpace-vs-resend" }, "tokens": { "markdown": 5250, "slim": 3280 }, "version": 1 }