{ "data": { "a": { "slug": "mailchimp-marketing", "name": "Mailchimp Marketing API", "vendor": "Intuit Mailchimp", "vendorUrl": "https://mailchimp.com", "kind": "http-api", "category": "lifecycle-marketing", "summary": "Intuit Mailchimp's Marketing API manages audiences, contacts, tags, segments, events, campaigns, automations and reports for a Mailchimp account. It is a REST API at `https://api.mailchimp.com/3.0/` that takes an API key or an OAuth 2 token.", "url": "https://www.anchorterminal.com/tools/mailchimp-marketing", "markdownUrl": "https://www.anchorterminal.com/tools/mailchimp-marketing.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/mailchimp-marketing.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/mailchimp-marketing.json", "repo": "https://github.com/mailchimp/mailchimp-marketing-typescript-sdk", "license": "Proprietary service under Mailchimp's Standard Terms of Use and API Use Policy. The generated client libraries declare Apache-2.0 in their package metadata", "transports": [ "http" ], "remoteUrl": "https://api.mailchimp.com/3.0", "packages": [ { "registry": "npm", "name": "@mailchimp/mailchimp_marketing" }, { "registry": "pypi", "name": "mailchimp-marketing" } ], "auth": "mixed", "authNotes": "Self-serve API key, or an OAuth 2 token for another user's account. A user with Manager permissions or above creates a key under Profile, Extras, API keys, and it is shown once. A key has full account access, bounded only by its creator's user level, with no read-only or per-endpoint option. Keys created from 22 June 2026 expire after one year, per the help centre. OAuth uses the authorisation code grant with no scopes, no refresh token and tokens that do not expire. Registering an OAuth app is done in the account, and a Marketplace listing needs OAuth. Both credentials go in HTTP Basic or `Authorization: Bearer`.", "pricing": "freemium", "pricingNotes": "The Free plan has 250 contacts and 500 sends a month (250 a day), one audience and one seat, with no time limit. Paid plans start at $13 a month for Essentials, $20 for Standard and $350 for Premium with USD selected, and rise with the contact count. API calls are not metered. The 14-day trial of a paid plan needs payment details. An agent's owner can start on the Free plan without a contract (https://mailchimp.com/pricing/marketing/, https://mailchimp.com/help/about-mailchimp-pricing-plans/).", "priceSummary": "$13 / mo", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the developer docs, the OpenAPI file or the pricing page (checked 2026-10-08).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": 278434, "pypiWeekly": 111433, "asOf": "2026-10-08" }, "docsUrl": "https://mailchimp.com/developer/marketing/", "llmsTxt": "https://mailchimp.com/developer/marketing/llms.txt", "openapi": "https://api.mailchimp.com/schema/openapi/OpenAPI.json?expand", "capabilities": [ "marketing.profiles", "marketing.events", "marketing.segments", "marketing.campaigns", "marketing.journeys", "email.templates" ], "tags": [ "official", "hosted", "closed-source", "api-key", "oauth", "openapi", "llms-txt", "free-tier", "webhooks", "cli", "typescript", "python", "go", "java", "status-page", "soc2" ], "lastRelease": "2026-10-05", "graded": true, "anchor": { "graded": true, "score": 57.4, "grade": "C", "agentReady": false, "rank": 609, "ranked": true, "rankOf": 950, "categoryRank": 6, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 73, "maintenance": 63, "payments": 25, "reliability": 60, "schema": 76, "security": 46, "transparency": 74 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-08" }, "negative": -2, "negativeNotes": [ "8 October 2026. The quick start tells users to run `npm install @mailchimp/mailchimp-marketing`, and the npm registry answers 404 for that name. Its `pip install mailchimp-marketing` installs version 3.0.80 from November 2022, which has no `MailchimpClient` class as the quick start's code needs. The Go, Ruby, Rust and PHP names resolve, so 2 for a claim the listing can't meet in two of nine languages (https://mailchimp.com/developer/marketing/build/start-developing/send-your-first-api-request.md, https://registry.npmjs.org/@mailchimp%2fmailchimp-marketing)." ], "verdict": "A public OpenAPI 3.1 file covers all 297 operations, every docs page has a Markdown copy, and responses can be trimmed with `fields`. An API key carries full account access with no read-only option. The quick start's TypeScript package was not on npm on 8 October 2026, and the changelog's newest entry is 19 August 2025.", "bestFor": "Small businesses already on Mailchimp that want an agent to sync contacts, tag and segment them, record events, draft and schedule campaigns and read reports.", "strengths": [ "OpenAPI 3.1 file for all 297 operations at `https://api.mailchimp.com/schema/openapi/OpenAPI.json`, with an error response on every operation", "`fields` and `exclude_fields` trim responses on 130 operations, and `count` pages up to 1,000 records", "Every docs page has a Markdown copy at the URL plus `.md`, with llms.txt indexes and four published agent skills", "Errors are `application/problem+json` with `title`, `status`, `detail` and `instance`, and an `X-Trigger-Error` header lets a client test its handling", "Free plan with 250 contacts and 500 sends a month, and a status page with an API component for each of 21 data centres" ], "weaknesses": [ "An API key has full account access. The docs say there is no read-only key and no way to limit a key to chosen endpoints", "OAuth 2 tokens carry no scopes and never expire, and no approval step before `actions/send` was found", "The quick start's `npm install @mailchimp/mailchimp-marketing` answered 404 on npm, and `pip install mailchimp-marketing` installs a 2022 library with a different client class", "The only stated limit is 10 simultaneous connections per user. No `Retry-After` header, idempotency key or SLA was found", "The developer changelog's newest entry is 19 August 2025, and the docs say keys never expire while the help centre says new keys expire after one year", "Click tracking was lost for about 25 hours on 3 and 4 August 2026 and cannot be backfilled, per the status page" ], "agentNotes": [ "Send the key or OAuth token as `Authorization: Bearer` to `https://api.mailchimp.com/3.0/`. Treat it as full account access and keep it server-side", "Address a contact by the MD5 hash of the lowercase email address, and use PUT on `/lists/{list_id}/members/{subscriber_hash}` so a retry does not create a duplicate", "Ask a person before POST `/campaigns/{campaign_id}/actions/send`. Read `/campaigns/{campaign_id}/send-checklist` and use `actions/test` first", "Keep to 10 concurrent requests per user, and send large jobs to `/batches`. A 429 names no wait time, so back off and retry", "Add `fields=` to every list call and set `count` (default 10, maximum 1,000) with `offset`", "Set `is_syncing` to true when loading historical events so they do not trigger automations" ], "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": 57.4 } ], "editorialScores": { "ergonomics": 73, "maintenance": 63, "payments": 25, "reliability": 60, "schema": 76, "security": 46, "transparency": 55 }, "provenanceScore": 92 }, "connect": { "http": "curl -sS \\\n \"https://api.mailchimp.com/3.0/ping\" \\\n --user \"anystring:${apikey}\"", "claudeCode": "claude mcp add --transport http fern_mcp_mailchimp-docs \\\n https://mailchimp.com/developer/_mcp/server", "config": { "mcpServers": { "mailchimp-docs": { "type": "http", "url": "https://mailchimp.com/developer/_mcp/server" } } } }, "letme": { "capability": "https://letme.dev/marketing.profiles", "tool": "https://letme.dev/mailchimp-marketing" }, "sameCompany": [ "mandrill" ], "area": "communication", "unitPrices": [ { "item": "Essentials plan, up to 500 contacts", "unit": "month", "usd": 13, "note": "starting price with USD selected, rises with contacts" }, { "item": "Standard plan, up to 500 contacts", "unit": "month", "usd": 20, "note": "starting price with USD selected, rises with contacts" }, { "item": "Premium plan, starting price", "unit": "month", "usd": 350, "note": "starting price with USD selected, rises with contacts" } ], "provenance": { "legalEntity": "The Rocket Science Group LLC d/b/a Mailchimp", "domain": "mailchimp.com", "domainRegistered": "2001-06-29", "endpointOnVendorDomain": true, "terms": "https://mailchimp.com/legal/terms/", "privacy": "https://www.intuit.com/privacy/statement/", "statusPage": "https://status.mailchimp.com", "changelog": "https://mailchimp.com/developer/release-notes/", "securityTxt": "valid", "checked": "2026-10-08", "notes": [ "The Standard Terms of Use, updated and effective 10 October 2025, name The Rocket Science Group LLC d/b/a Mailchimp, 405 N Angier Ave. NE, Atlanta, Georgia. API use is also governed by the API Use Policy at https://mailchimp.com/legal/api_use/, updated 1 August 2023, which the terms incorporate.", "The privacy field points at the Intuit Global Privacy Statement, last updated 9 March 2026. mailchimp.com/legal/privacy redirects to it, the terms name it as the privacy document for the service, and it names The Rocket Science Group LLC d/b/a Mailchimp. Mailchimp publishes no separate privacy policy.", "The API answers at api.mailchimp.com. An unauthenticated request to `/3.0/ping` returned 401 as `application/problem+json` on 8 October 2026.", "mailchimp.com/.well-known/security.txt holds one Contact line that points at the responsible disclosure section of the security page, with no Expires field. The value follows the reading on the Mailchimp Transactional listing.", "The changelog covers the Marketing and Transactional APIs together. Its newest entry is dated 19 August 2025, and its newest Marketing entry 7 August 2025.", "RDAP for mailchimp.com gives a registration date of 2001-06-29 (Verisign)." ], "score": 92 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/mailchimp-marketing.json", "live": { "slug": "mailchimp-marketing", "probe": { "target": "https://api.mailchimp.com/3.0", "method": "get", "lastAt": "2026-10-10T02:55:01.101325434Z", "lastOk": true, "lastStatus": 401, "lastMs": 317, "lastNote": "asks for credentials", "authRequired": true, "uptime24h": 99.5, "uptime30d": 99.5, "p50ms24h": 316, "p95ms24h": 516, "samples24h": 199, "samples30d": 199, "days": [ { "date": "2026-10-09", "probes": 169, "ok": 168 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "vendorStatus": { "page": "https://status.mailchimp.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-10T00:50:46.815731894Z" }, "versions": [ { "registry": "github", "name": "mailchimp/mailchimp-marketing-typescript-sdk", "version": "1.0.3", "released": "2026-10-05", "seenAt": "2026-10-09T17:03:25.010553211Z" }, { "registry": "npm", "name": "@mailchimp/mailchimp_marketing", "version": "3.0.80", "seenAt": "2026-10-09T17:03:23.925729063Z" }, { "registry": "pypi", "name": "mailchimp-marketing", "version": "3.0.80", "released": "2022-11-02", "seenAt": "2026-10-09T17:03:24.813754429Z" } ], "githubStars": 0, "npmWeekly": 230835, "pypiWeekly": 111727, "securityTxt": { "url": "https://mailchimp.com/.well-known/security.txt", "state": "valid", "checkedAt": "2026-10-09T15:40:06.339407223Z" }, "llmsTxt": { "url": "https://mailchimp.com/developer/marketing/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-09T14:02:15.064783349Z" }, "pages": [ { "url": "https://mailchimp.com/developer/release-notes/", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:41:40.46239945Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "73f208452255" }, { "url": "https://mailchimp.com/help/about-mailchimp-pricing-plans/", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:41:43.291283234Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "174dbb82057e" }, { "url": "https://mailchimp.com/pricing/marketing/", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:41:46.531152174Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "9acf2507300c" }, { "url": "https://www.intuit.com/privacy/statement/", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:51:15.940538743Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "bdf88eaea616" }, { "url": "https://mailchimp.com/legal/terms/", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:41:44.586074781Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "24853a4c12ab" } ], "updatedAt": "2026-10-10T02:55:01.101325434Z" } }, "answer": "Omnisend scores 64.9 (B) on agent readiness against Mailchimp Marketing API's 57.4 (C), and leads in 6 of 7 scored categories. Mailchimp Marketing API leads on maintenance \u0026 community.", "b": { "slug": "omnisend", "name": "Omnisend", "vendor": "Omnisend, UAB", "vendorUrl": "https://www.omnisend.com", "kind": "http-api", "category": "lifecycle-marketing", "summary": "Omnisend is an email, SMS and push marketing platform for online shops. Agents reach contacts, events, segments, campaigns, automations and forms through a REST API with dated versions and an official hosted MCP server.", "url": "https://www.anchorterminal.com/tools/omnisend", "markdownUrl": "https://www.anchorterminal.com/tools/omnisend.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/omnisend.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/omnisend.json", "license": "Proprietary service under Omnisend's Terms of Use", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.omnisend.com/api", "packages": [], "auth": "mixed", "authNotes": "Access is self-serve with an API key. A user creates a named key in the app under API keys, copies it once, and sends it as `Authorization: Omnisend-API-Key \u003ckey\u003e` with `Omnisend-Version: 2026-03-15`. OAuth 2.0 with the authorisation code grant and per-resource scopes is for apps, and credentials are issued through a request form in one to three business days. The hosted MCP server takes OAuth with dynamic client registration, needs the Owner, Admin, Manager or Partner role, and asks for an access level on the consent screen. Whether an API key can be limited to scopes was not found in the pages read.", "pricing": "freemium", "pricingNotes": "Free plan with 250 contacts and 500 emails a month, no credit card required, so an agent's owner can start without a contract. Paid plans scale with contacts through a slider. At the page's defaults Standard (500 contacts, 6,000 emails a month) shows $11.20 a month for the first three months against a three-month total of $48.00, and Pro (2,500 contacts, unlimited emails) $41.30 against $177.00. SMS starts at $0.007 a message. API calls aren't metered, and the page lists Omnisend MCP under every plan (https://www.omnisend.com/pricing/, checked 2026-10-09).", "priceSummary": "$16 / mo", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the API documentation or the pricing page. The 402 response on the send campaign endpoint is an ordinary plan payment error (checked 2026-10-09).", "endpoints": [] }, "toolCount": 4, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-09" }, "docsUrl": "https://api-docs.omnisend.com/", "llmsTxt": "https://api-docs.omnisend.com/llms.txt", "capabilities": [ "marketing.profiles", "marketing.events", "marketing.segments", "marketing.campaigns", "marketing.journeys", "email.templates", "forms.create" ], "tags": [ "official", "hosted", "mcp", "closed-source", "oauth", "llms-txt", "free-tier", "no-card", "status-page", "bug-bounty" ], "lastRelease": "2026-07-10", "graded": true, "anchor": { "graded": true, "score": 64.9, "grade": "B", "agentReady": false, "rank": 334, "ranked": true, "rankOf": 950, "categoryRank": 4, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 79, "maintenance": 29, "payments": 30, "reliability": 81, "schema": 79, "security": 57, "transparency": 77 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-09" }, "negative": 0, "verdict": "The API documents 104 operations with per-operation OpenAPI definitions, cursor pagination, RFC 9457 errors and published rate limits, and the hosted MCP server fronts them with four tools and a read-only consent preset. No approval hold before a campaign send, no idempotency keys, no SLA and no official SDK were found in the reviewed documentation.", "bestFor": "Online shops already on Omnisend that want an agent to read campaign results, manage contacts and segments, and draft campaigns or automations.", "strengths": [ "Each of the 104 documented operations has a Markdown page with its OpenAPI 3.0 definition, required scopes and rate limit, indexed in `llms.txt`", "The hosted MCP server lists four tools (`search`, `tool_schema`, `tool_documentation`, `execute`) in front of the whole API, with a read-only preset on the OAuth consent screen", "Errors follow RFC 9457 with a field-level `errors` array that reports every validation failure at once, plus a trace ID in `instance`", "Rate limits are published per endpoint, 400 requests a minute by default on a sliding window per brand", "The Free plan has 250 contacts and 500 emails a month, and the pricing page says no credit card is required", "The status page has an API component and its history feed shows no incident between 27 May and 9 October 2026" ], "weaknesses": [ "No approval or hold step before `POST /campaigns/{id}/send` was found. The terms make the customer responsible for approving each action an AI agent takes", "No idempotency keys were found. Event `eventID` deduplicates historical events only, not real-time events that trigger automations", "OAuth client credentials for the REST API are issued through a request form in one to three business days, and access tokens never expire unless the user revokes them", "No SLA was found, and the terms say scheduled or unscheduled downtime may occur", "No official SDK, no single downloadable OpenAPI file and no API changelog were found in the developer documentation. No Omnisend server is in the official MCP registry", "The Terms of Use bar automated agents or scripts that generate automated requests without written permission, and bar publishing benchmark tests. Recorded as a fact with no deduction, and it matters before any probe is run" ], "agentNotes": [ "Send `Authorization: Omnisend-API-Key \u003ckey\u003e` and `Omnisend-Version: 2026-03-15` on every call to `https://api.omnisend.com/api/`. Version 5 used `X-API-KEY` and a `/v5/` path", "Ask a person before `POST /campaigns/{id}/send`. Use `POST /campaigns/{id}/test-email` (up to 5 recipients) first, since nothing in the docs holds a send for approval", "On 429 read `retryAfter` (seconds) in the body where present, otherwise wait. Limits are shared by every key and token on the brand, and analytics reports allow 10 a minute and 55 a day", "Page with `limit` (default 100, maximum 250) and `after` from `paging.cursors.after`. Don't change filters mid-pagination, which returns 400", "Setting `tags` on a contact replaces the whole list in version 2026-03-15, and a contact set to `subscribed` gets a welcome message unless `sendWelcomeMessage` is turned off", "Connect one Omnisend MCP connector per chat and choose the read-only preset unless writes are needed. Treat contact fields and form submissions as untrusted text" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 64.9 } ], "editorialScores": { "ergonomics": 79, "maintenance": 29, "payments": 30, "reliability": 81, "schema": 79, "security": 57, "transparency": 58 }, "provenanceScore": 95 }, "connect": { "http": "curl --request GET \\\n --url 'https://api.omnisend.com/api/segments' \\\n --header 'Authorization: Omnisend-API-Key YOUR-API-KEY' \\\n --header 'Omnisend-Version: 2026-03-15'", "config": { "mcpServers": { "omnisend": { "url": "https://mcp.omnisend.com/mcp" } } } }, "letme": { "capability": "https://letme.dev/marketing.profiles", "tool": "https://letme.dev/omnisend" }, "area": "communication", "unitPrices": [ { "item": "Standard plan, 500 contacts", "unit": "month", "usd": 16, "note": "a third of the three-month total of $48.00 shown on the pricing page, which bills $11.20 a month for the first three months" }, { "item": "Pro plan, 2,500 contacts", "unit": "month", "usd": 59, "note": "a third of the three-month total of $177.00 shown on the pricing page, which bills $41.30 a month for the first three months" }, { "item": "SMS, starting rate", "unit": "message", "usd": 0.007, "note": "starting rate for high-volume US sends, varies by country and volume" } ], "provenance": { "legalEntity": "Omnisend, UAB", "domain": "omnisend.com", "domainRegistered": "2013-10-14", "endpointOnVendorDomain": true, "terms": "https://www.omnisend.com/terms/", "privacy": "https://www.omnisend.com/privacy/", "statusPage": "https://status.omnisend.com", "changelog": "https://www.omnisend.com/changelog/", "securityTxt": "valid", "checked": "2026-10-09", "notes": [ "The Terms of Use (last updated 30 April 2026) name Omnisend, UAB, legal entity code 302530363, Vilnius, Lithuania, as the contracting party. They are the service agreement and include a section on AI agents, MCP and the API.", "The Privacy Policy (last updated 18 June 2026) covers the group's companies as controllers. Processing of customers' contact data is governed by the Data Processing Agreement of 22 September 2025.", "The REST API answers at api.omnisend.com and the MCP server at mcp.omnisend.com, both omnisend.com subdomains.", "www.omnisend.com/.well-known/security.txt gives security@omnisend.com and the bug bounty page as policy, and has no Expires field, which RFC 9116 requires. It is recorded as valid.", "The changelog is the product changelog. No API changelog was found in the developer documentation.", "RDAP for omnisend.com gives a registration date of 2013-10-14." ], "score": 95 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/omnisend.json", "live": { "slug": "omnisend", "probe": { "target": "https://api.omnisend.com/api", "method": "get", "lastAt": "2026-10-10T02:55:04.154516897Z", "lastOk": true, "lastStatus": 404, "lastMs": 159, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 153, "p95ms24h": 258, "samples24h": 115, "samples30d": 115, "days": [ { "date": "2026-10-09", "probes": 85, "ok": 85 }, { "date": "2026-10-10", "probes": 30, "ok": 30 } ] }, "vendorStatus": { "page": "https://status.omnisend.com", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-10T02:50:29.851229446Z" }, "pages": [ { "url": "https://www.omnisend.com/changelog/", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:52:40.626914195Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "4ee91ee1c9c0" }, { "url": "https://www.omnisend.com/pricing/", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:52:43.649861328Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "a4f809f8a468" }, { "url": "https://www.omnisend.com/privacy/", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:52:45.267503247Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "2fe5ad4e76ef" }, { "url": "https://www.omnisend.com/terms/", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:52:47.254298905Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "8732e799e365" } ], "updatedAt": "2026-10-10T02:55:04.154516897Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "Intuit Mailchimp", "b": "Omnisend, UAB", "name": "Vendor" }, { "a": "https://api.mailchimp.com/3.0", "b": "https://api.omnisend.com/api", "name": "Hosted endpoint" }, { "a": "HTTP", "b": "HTTP, Streamable HTTP", "name": "Transports" }, { "a": "OAuth or key", "b": "OAuth or key", "name": "Auth" }, { "a": "Freemium", "b": "Freemium", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "Proprietary service under Mailchimp's Standard Terms of Use and API Use Policy. The generated client libraries declare Apache-2.0 in their package metadata", "b": "Proprietary service under Omnisend's Terms of Use", "name": "Licence" }, { "a": "none", "b": "4", "name": "Tools exposed" }, { "a": "no", "b": "yes", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-10-05", "b": "2026-07-10", "name": "Last release" }, { "a": "no date given", "b": "2026-04-30", "name": "Terms last updated" }, { "a": "2026-03-09", "b": "2026-06-18", "name": "Privacy policy last updated" }, { "a": "yes", "b": "not found in the text", "name": "Customer content may train models" }, { "a": "not found in the text", "b": "yes", "name": "Terms restrict automated access" }, { "a": "not found in the text", "b": "yes", "name": "Terms restrict benchmarking" }, { "a": "yes", "b": "not found in the text", "name": "Terms or service can change without notice" }, { "a": "yes", "b": "not found in the text", "name": "Arbitration or class-action waiver" }, { "a": "278k npm/wk, 111k PyPI/wk", "b": "none", "name": "Popularity" } ], "faq": [ { "answer": "Omnisend scores 64.9 (B) on agent readiness against Mailchimp Marketing API's 57.4 (C), and leads in 6 of 7 scored categories. Mailchimp Marketing API leads on maintenance \u0026 community.", "question": "Which is better for AI agents, Mailchimp Marketing API or Omnisend?" }, { "answer": "Both take an API key or an OAuth sign-in.", "question": "Do Mailchimp Marketing API and Omnisend need an API key?" }, { "answer": "Yes. Mailchimp Marketing API has a hosted endpoint at https://api.mailchimp.com/3.0 and Omnisend at https://api.omnisend.com/api.", "question": "Can an agent call Mailchimp Marketing API and Omnisend without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Maintenance \u0026 community, 63 against 29" ], "also": null, "goodFor": "Small businesses already on Mailchimp that want an agent to sync contacts, tag and segment them, record events, draft and schedule campaigns and read reports.", "slug": "mailchimp-marketing", "watchFor": "An API key has full account access. The docs say there is no read-only key and no way to limit a key to chosen endpoints" }, { "aheadOn": [ "Reliability, 81 against 60", "Agent ergonomics, 79 against 73", "Security \u0026 auth, 57 against 46", "Payments \u0026 pricing, 30 against 25" ], "also": [ "Free to start without a card" ], "goodFor": "Online shops already on Omnisend that want an agent to read campaign results, manage contacts and segments, and draft campaigns or automations.", "slug": "omnisend", "watchFor": "No approval or hold step before `POST /campaigns/{id}/send` was found. The terms make the customer responsible for approving each action an AI agent takes" } ], "job": { "capability": "marketing.profiles", "name": "Marketing audiences" }, "others": [ { "json": "https://www.anchorterminal.com/compare/activecampaign-vs-mailchimp-marketing.json", "title": "ActiveCampaign vs Mailchimp Marketing API", "url": "https://www.anchorterminal.com/compare/activecampaign-vs-mailchimp-marketing" }, { "json": "https://www.anchorterminal.com/compare/activecampaign-vs-omnisend.json", "title": "ActiveCampaign vs Omnisend", "url": "https://www.anchorterminal.com/compare/activecampaign-vs-omnisend" }, { "json": "https://www.anchorterminal.com/compare/braze-vs-mailchimp-marketing.json", "title": "Braze vs Mailchimp Marketing API", "url": "https://www.anchorterminal.com/compare/braze-vs-mailchimp-marketing" }, { "json": "https://www.anchorterminal.com/compare/braze-vs-omnisend.json", "title": "Braze vs Omnisend", "url": "https://www.anchorterminal.com/compare/braze-vs-omnisend" }, { "json": "https://www.anchorterminal.com/compare/clevertap-vs-mailchimp-marketing.json", "title": "CleverTap vs Mailchimp Marketing API", "url": "https://www.anchorterminal.com/compare/clevertap-vs-mailchimp-marketing" }, { "json": "https://www.anchorterminal.com/compare/clevertap-vs-omnisend.json", "title": "CleverTap vs Omnisend", "url": "https://www.anchorterminal.com/compare/clevertap-vs-omnisend" }, { "json": "https://www.anchorterminal.com/compare/customer-io-vs-mailchimp-marketing.json", "title": "Customer.io vs Mailchimp Marketing API", "url": "https://www.anchorterminal.com/compare/customer-io-vs-mailchimp-marketing" }, { "json": "https://www.anchorterminal.com/compare/customer-io-vs-omnisend.json", "title": "Customer.io vs Omnisend", "url": "https://www.anchorterminal.com/compare/customer-io-vs-omnisend" }, { "json": "https://www.anchorterminal.com/compare/iterable-vs-mailchimp-marketing.json", "title": "Iterable vs Mailchimp Marketing API", "url": "https://www.anchorterminal.com/compare/iterable-vs-mailchimp-marketing" }, { "json": "https://www.anchorterminal.com/compare/iterable-vs-omnisend.json", "title": "Iterable vs Omnisend", "url": "https://www.anchorterminal.com/compare/iterable-vs-omnisend" }, { "json": "https://www.anchorterminal.com/compare/klaviyo-vs-mailchimp-marketing.json", "title": "Klaviyo API + MCP vs Mailchimp Marketing API", "url": "https://www.anchorterminal.com/compare/klaviyo-vs-mailchimp-marketing" }, { "json": "https://www.anchorterminal.com/compare/klaviyo-vs-omnisend.json", "title": "Klaviyo API + MCP vs Omnisend", "url": "https://www.anchorterminal.com/compare/klaviyo-vs-omnisend" }, { "json": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-moengage.json", "title": "Mailchimp Marketing API vs MoEngage", "url": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-moengage" }, { "json": "https://www.anchorterminal.com/compare/moengage-vs-omnisend.json", "title": "MoEngage vs Omnisend", "url": "https://www.anchorterminal.com/compare/moengage-vs-omnisend" } ], "scores": [ { "by": 21, "edge": "omnisend", "key": "reliability", "mailchimp-marketing": 60, "name": "Reliability", "omnisend": 81, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 3, "edge": "omnisend", "key": "schema", "mailchimp-marketing": 76, "name": "Schema \u0026 documentation", "omnisend": 79, "weight": 13 }, { "by": 6, "edge": "omnisend", "key": "ergonomics", "mailchimp-marketing": 73, "name": "Agent ergonomics", "omnisend": 79, "weight": 13 }, { "by": 11, "edge": "omnisend", "key": "security", "mailchimp-marketing": 46, "name": "Security \u0026 auth", "omnisend": 57, "weight": 14 }, { "by": 5, "edge": "omnisend", "key": "payments", "mailchimp-marketing": 25, "name": "Payments \u0026 pricing", "omnisend": 30, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 34, "edge": "mailchimp-marketing", "key": "maintenance", "mailchimp-marketing": 63, "name": "Maintenance \u0026 community", "omnisend": 29, "weight": 7 }, { "by": 3, "edge": "omnisend", "key": "transparency", "mailchimp-marketing": 74, "name": "Transparency \u0026 trust", "omnisend": 77, "weight": 7 } ], "summary": "Omnisend scores 64.9 (B) on agent readiness against Mailchimp Marketing API's 57.4 (C), and leads in 6 of 7 scored categories. Mailchimp Marketing API leads on maintenance \u0026 community. Both do marketing audiences.", "verdicts": { "mailchimp-marketing": "A public OpenAPI 3.1 file covers all 297 operations, every docs page has a Markdown copy, and responses can be trimmed with `fields`. An API key carries full account access with no read-only option. The quick start's TypeScript package was not on npm on 8 October 2026, and the changelog's newest entry is 19 August 2025.", "omnisend": "The API documents 104 operations with per-operation OpenAPI definitions, cursor pagination, RFC 9457 errors and published rate limits, and the hosted MCP server fronts them with four tools and a read-only consent preset. No approval hold before a campaign send, no idempotency keys, no SLA and no official SDK were found in the reviewed documentation." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend", "json": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend.md", "slim": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend.min.md" }, "markdown": "Omnisend scores 64.9 (B) on agent readiness against Mailchimp Marketing API's 57.4 (C), and leads in 6 of 7 scored categories. Mailchimp Marketing API leads on maintenance \u0026 community. Both do marketing audiences.\n\n- Mailchimp Marketing API: grade C, 57.4/100, rank #609 of 950. Markdown https://www.anchorterminal.com/tools/mailchimp-marketing.md · JSON https://www.anchorterminal.com/api/v1/tools/mailchimp-marketing.json\n- Omnisend: grade B, 64.9/100, rank #334 of 950. Markdown https://www.anchorterminal.com/tools/omnisend.md · JSON https://www.anchorterminal.com/api/v1/tools/omnisend.json\n- Best lifecycle marketing and customer engagement platforms for AI agents: https://www.anchorterminal.com/best/lifecycle-marketing/index.md\n- All 36 lifecycle marketing comparisons: https://www.anchorterminal.com/compare/lifecycle-marketing/index.md\n\n## Which one, for what\n\n### Mailchimp Marketing API (C)\n\nGood for: Small businesses already on Mailchimp that want an agent to sync contacts, tag and segment them, record events, draft and schedule campaigns and read reports.\n\nAhead on:\n- Maintenance \u0026 community, 63 against 29\n\nWatch for: An API key has full account access. The docs say there is no read-only key and no way to limit a key to chosen endpoints\n\n### Omnisend (B)\n\nGood for: Online shops already on Omnisend that want an agent to read campaign results, manage contacts and segments, and draft campaigns or automations.\n\nAhead on:\n- Reliability, 81 against 60\n- Agent ergonomics, 79 against 73\n- Security \u0026 auth, 57 against 46\n- Payments \u0026 pricing, 30 against 25\n\nAlso in its favour:\n- Free to start without a card\n\nWatch for: No approval or hold step before `POST /campaigns/{id}/send` was found. The terms make the customer responsible for approving each action an AI agent takes\n\n\n## Score by category\n\n| Category | Weight | Mailchimp Marketing API | Omnisend | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 60 | 81 | Omnisend +21 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 76 | 79 | Omnisend +3 |\n| Agent ergonomics | 13% (16.2 this run) | 73 | 79 | Omnisend +6 |\n| Security \u0026 auth | 14% (17.5 this run) | 46 | 57 | Omnisend +11 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 25 | 30 | Omnisend +5 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 63 | 29 | Mailchimp Marketing API +34 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 74 | 77 | Omnisend +3 |\n| Negative events | ≤15 | -2 | 0 | |\n| **Total** | | **57.4 · C** | **64.9 · B** | |\n\n## Facts side by side\n\n| Fact | Mailchimp Marketing API | Omnisend |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Intuit Mailchimp | Omnisend, UAB |\n| Hosted endpoint | `https://api.mailchimp.com/3.0` | `https://api.omnisend.com/api` |\n| Transports | HTTP | HTTP, Streamable HTTP |\n| Auth | OAuth or key | OAuth or key |\n| Pricing | Freemium | Freemium |\n| x402 | no | no |\n| Licence | Proprietary service under Mailchimp's Standard Terms of Use and API Use Policy. The generated client libraries declare Apache-2.0 in their package metadata | Proprietary service under Omnisend's Terms of Use |\n| Tools exposed | none | 4 |\n| Read-only variant documented | no | yes |\n| llms.txt | yes | yes |\n| Last release | 2026-10-05 | 2026-07-10 |\n| Terms last updated | no date given | 2026-04-30 |\n| Privacy policy last updated | 2026-03-09 | 2026-06-18 |\n| Customer content may train models | yes | not found in the text |\n| Terms restrict automated access | not found in the text | yes |\n| Terms restrict benchmarking | not found in the text | yes |\n| Terms or service can change without notice | yes | not found in the text |\n| Arbitration or class-action waiver | yes | not found in the text |\n| Popularity | 278k npm/wk, 111k PyPI/wk | none |\n\n## Verdicts\n\n**Mailchimp Marketing API.** A public OpenAPI 3.1 file covers all 297 operations, every docs page has a Markdown copy, and responses can be trimmed with `fields`. An API key carries full account access with no read-only option. The quick start's TypeScript package was not on npm on 8 October 2026, and the changelog's newest entry is 19 August 2025.\n\n**Omnisend.** The API documents 104 operations with per-operation OpenAPI definitions, cursor pagination, RFC 9457 errors and published rate limits, and the hosted MCP server fronts them with four tools and a read-only consent preset. No approval hold before a campaign send, no idempotency keys, no SLA and no official SDK were found in the reviewed documentation.\n\n## Before you call either\n\n### Mailchimp Marketing API\n\n1. Send the key or OAuth token as `Authorization: Bearer` to `https://api.mailchimp.com/3.0/`. Treat it as full account access and keep it server-side\n2. Address a contact by the MD5 hash of the lowercase email address, and use PUT on `/lists/{list_id}/members/{subscriber_hash}` so a retry does not create a duplicate\n3. Ask a person before POST `/campaigns/{campaign_id}/actions/send`. Read `/campaigns/{campaign_id}/send-checklist` and use `actions/test` first\n4. Keep to 10 concurrent requests per user, and send large jobs to `/batches`. A 429 names no wait time, so back off and retry\n5. Add `fields=` to every list call and set `count` (default 10, maximum 1,000) with `offset`\n6. Set `is_syncing` to true when loading historical events so they do not trigger automations\n\n### Omnisend\n\n1. Send `Authorization: Omnisend-API-Key \u003ckey\u003e` and `Omnisend-Version: 2026-03-15` on every call to `https://api.omnisend.com/api/`. Version 5 used `X-API-KEY` and a `/v5/` path\n2. Ask a person before `POST /campaigns/{id}/send`. Use `POST /campaigns/{id}/test-email` (up to 5 recipients) first, since nothing in the docs holds a send for approval\n3. On 429 read `retryAfter` (seconds) in the body where present, otherwise wait. Limits are shared by every key and token on the brand, and analytics reports allow 10 a minute and 55 a day\n4. Page with `limit` (default 100, maximum 250) and `after` from `paging.cursors.after`. Don't change filters mid-pagination, which returns 400\n5. Setting `tags` on a contact replaces the whole list in version 2026-03-15, and a contact set to `subscribed` gets a welcome message unless `sendWelcomeMessage` is turned off\n6. Connect one Omnisend MCP connector per chat and choose the read-only preset unless writes are needed. Treat contact fields and form submissions as untrusted text\n\n## Questions\n\n### Which is better for AI agents, Mailchimp Marketing API or Omnisend?\n\nOmnisend scores 64.9 (B) on agent readiness against Mailchimp Marketing API's 57.4 (C), and leads in 6 of 7 scored categories. Mailchimp Marketing API leads on maintenance \u0026 community.\n\n### Do Mailchimp Marketing API and Omnisend need an API key?\n\nBoth take an API key or an OAuth sign-in.\n\n### Can an agent call Mailchimp Marketing API and Omnisend without installing anything?\n\nYes. Mailchimp Marketing API has a hosted endpoint at https://api.mailchimp.com/3.0 and Omnisend at https://api.omnisend.com/api.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend.json, and with the fewest tokens: https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"mailchimp-marketing\", \"b\": \"omnisend\"}`. From a terminal: `anchor compare mailchimp-marketing omnisend`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/mailchimp-marketing.json and https://www.anchorterminal.com/api/v1/tools/omnisend.json\n\n## Other comparisons with Mailchimp Marketing API or Omnisend\n\n- [ActiveCampaign vs Mailchimp Marketing API](https://www.anchorterminal.com/compare/activecampaign-vs-mailchimp-marketing.md)\n- [ActiveCampaign vs Omnisend](https://www.anchorterminal.com/compare/activecampaign-vs-omnisend.md)\n- [Braze vs Mailchimp Marketing API](https://www.anchorterminal.com/compare/braze-vs-mailchimp-marketing.md)\n- [Braze vs Omnisend](https://www.anchorterminal.com/compare/braze-vs-omnisend.md)\n- [CleverTap vs Mailchimp Marketing API](https://www.anchorterminal.com/compare/clevertap-vs-mailchimp-marketing.md)\n- [CleverTap vs Omnisend](https://www.anchorterminal.com/compare/clevertap-vs-omnisend.md)\n- [Customer.io vs Mailchimp Marketing API](https://www.anchorterminal.com/compare/customer-io-vs-mailchimp-marketing.md)\n- [Customer.io vs Omnisend](https://www.anchorterminal.com/compare/customer-io-vs-omnisend.md)\n- [Iterable vs Mailchimp Marketing API](https://www.anchorterminal.com/compare/iterable-vs-mailchimp-marketing.md)\n- [Iterable vs Omnisend](https://www.anchorterminal.com/compare/iterable-vs-omnisend.md)\n- [Klaviyo API + MCP vs Mailchimp Marketing API](https://www.anchorterminal.com/compare/klaviyo-vs-mailchimp-marketing.md)\n- [Klaviyo API + MCP vs Omnisend](https://www.anchorterminal.com/compare/klaviyo-vs-omnisend.md)\n- [Mailchimp Marketing API vs MoEngage](https://www.anchorterminal.com/compare/mailchimp-marketing-vs-moengage.md)\n- [MoEngage vs Omnisend](https://www.anchorterminal.com/compare/moengage-vs-omnisend.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-10", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Mailchimp Marketing API vs Omnisend", "url": "" } ], "description": "Omnisend scores 64.9 (B) to Mailchimp Marketing's 57.4 (C) for marketing audiences. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "Mailchimp Marketing API C 57.4", "Omnisend B 64.9", "scores" ], "h1": "Mailchimp Marketing API vs Omnisend", "image": "https://www.anchorterminal.com/assets/og/compare-mailchimp-marketing-vs-omnisend.png", "path": "/compare/mailchimp-marketing-vs-omnisend", "published": "2026-10-01", "section": "tools", "title": "Mailchimp Marketing vs Omnisend for AI agents (2026) | Anchor Terminal", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/compare/mailchimp-marketing-vs-omnisend" }, "tokens": { "markdown": 2500, "slim": 730 }, "version": 1 }