Get an audit

Head to head · Backlink data · October 2026 research run

Majestic API vs Semrush API + MCP

Semrush API + MCP scores 53.1 (D) on agent readiness against Majestic API's 33.4 (F), and leads in every scored category. Both do backlink data.

Best SEO and search visibility data for AI agents · All 45 seo comparisons

Majestic APIMajestic (Majestic-12 Limited) · HTTP API F33.4/100#937 of 950 Semrush API + MCPSemrush Inc. (an Adobe company) · HTTP API D53.1/100#721 of 950

Which one, for what

Majestic API F

Good for An agent that needs backlink, referring domain, anchor text and Trust Flow data in volume for an owner who already pays for the API plan.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Clause 14.1(f) of the supply terms forbids querying Majestic's database or servers with automated tools without prior permission. This matters before any probe is run

Semrush API + MCP D

Good for Teams already paying for Semrush who want an agent to pull keyword, backlink, ranking and traffic estimates in one place, mainly through the MCP server.

Ahead on

  • Reliability, 34 against 17
  • Schema & documentation, 70 against 44
  • Agent ergonomics, 77 against 54
  • Security & auth, 54 against 32
  • Maintenance & community, 57 against 22
  • Transparency & trust, 67 against 53

Watch for

Domain, URL, Trends, Position Tracking and Site Audit reports are version 3 only, where the one key is a URL parameter and can't be revoked

Score by category

CategoryWeight this runMajestic APISemrush API + MCPEdge
Reliability16%201734Semrush API + MCP +17
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.24470Semrush API + MCP +26
Agent ergonomics13%16.25477Semrush API + MCP +23
Security & auth14%17.53254Semrush API + MCP +22
Payments & pricing10%12.51517Semrush API + MCP +2
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.82257Semrush API + MCP +35
Transparency & trust7%8.85367Semrush API + MCP +14
Negative events≤1500
Total33.4 · F53.1 · D

Facts side by side

FactMajestic APISemrush API + MCP
KindHTTP APIHTTP API
VendorMajestic (Majestic-12 Limited)Semrush Inc. (an Adobe company)
Hosted endpointhttps://api.majestic.comhttps://api.semrush.com
TransportsHTTPHTTP, Streamable HTTP
AuthAPI keyOAuth or key
PricingPaidPaid
x402nono
LicenceProprietary service under Majestic's Terms and Conditions. The Python 3 connector on GitHub carries a BSD-style licence fileProprietary service under the Semrush terms of service
Tools exposednone14
Read-only variant documentednoyes
llms.txtyesyes
Last releasenone2026-09-04
Terms last updatedno date given2026-08-25
Privacy policy last updated2026-04-012025-10-13
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessyesyes
Terms restrict benchmarkingnot found in the textyes
Terms or service can change without noticeyesnot found in the text
Arbitration or class-action waivernot found in the textyes
Popularity3 starsnone

Verdicts

Majestic API

Each command's cost in units is published and a sandbox endpoint returns sample data without spending allowance. API access starts at $399.99 a month with no trial, and no OpenAPI file, status page, numeric rate limit, SLA or API changelog was found. The supply terms require permission before querying with automated tools.

Semrush API + MCP

The hosted MCP server exposes 14 tools that load a report's parameters on demand, and version 4 API keys can be read-only, time-limited and revoked. Most reports still sit in version 3, whose single key travels in the URL and can't be revoked. No status page, OpenAPI file or API unit price was found.

Before you call either

Majestic API

  1. Send requests by HTTPS POST with app_api_key in the body. The docs show GET URLs for demonstration only and plain HTTP still works
  2. Always set datasource=fresh or datasource=historic. Without it the Historic Index is used when the plan includes it
  3. Call GetSubscriptionInfo (no cost) before a large pull. GetBackLinkData spends 5,000 analysis units a call plus one retrieval unit a row
  4. Read columns by header name, not position. The docs say column order can change between requests and Majestic may vary rows and columns at any time
  5. Develop against https://developer.majestic.com/api/json, which costs no units, then switch the host to api.majestic.com
  6. Ask the owner to confirm Majestic's permission for automated querying first. Clause 14.1(f) of the terms requires it

Semrush API + MCP

  1. Use the MCP server at https://mcp.semrush.com/v2/mcp where the host supports it. Call a discovery tool, then get_report_schema, then execute_report
  2. Set limit or display_limit on every per-line report. A backlinks row costs 40 to 45 units and a historical keyword row 50
  3. Check the unit balance before large pulls. A per-line report returns only the lines the balance covers, with no error
  4. Send the version 4 key as Authorization: Apikey <key>, never as ?key=. Version 3 accepts only the query parameter, so keep those URLs out of logs
  5. Stay under 10 requests a second and 10 concurrent requests per account, and retry only when error.retryable is true

Questions

Which is better for AI agents, Majestic API or Semrush API + MCP?

Semrush API + MCP scores 53.1 (D) on agent readiness against Majestic API's 33.4 (F), and leads in every scored category.

Do Majestic API and Semrush API + MCP need an API key?

Majestic API needs an API key. Semrush API + MCP takes an API key or an OAuth sign-in.

Can an agent call Majestic API and Semrush API + MCP without installing anything?

Yes. Majestic API has a hosted endpoint at https://api.majestic.com and Semrush API + MCP at https://api.semrush.com.

Other comparisons with Majestic API or Semrush API + MCP

Machine-readable

For companies

Do agents find, use and choose your tools?

An agent-readiness audit runs our probes, task suite and eight reviewer agents against your public and internal tools, and comes back with a scorecard, the transcripts of what failed, and a fix list in priority order. From $2,500, re-run included. We never take payment to move a rank. We do help companies earn one.

Get an auditSee a sample report