Head to head · Seo keywords · October 2026 research run
Moz API vs Semrush API + MCP
Semrush API + MCP scores 53.1 (D) on agent readiness against Moz API's 45.3 (E), and leads in 5 of 7 scored categories. Moz API leads on reliability. Both do seo keywords.
Which one, for what
Moz API E
Good for Agents that need Domain Authority, backlink lists, link intersects, keyword volume and difficulty, search intent and ranking keywords at a low entry price, on a read-only data set.
Ahead on
- Reliability, 42 against 34
Watch for
No working public status page was found, and moz.statuspage.io reports the Moz Status page as inactive
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
- Schema & documentation, 70 against 50
- Security & auth, 54 against 38
- Maintenance & community, 57 against 28
- Transparency & trust, 67 against 59
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
| Category | Weight this run | Moz API | Semrush API + MCP | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 42 | 34 | Moz API +8 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 50 | 70 | Semrush API + MCP +20 |
| Agent ergonomics | 13%16.2 | 74 | 77 | Semrush API + MCP +3 |
| Security & auth | 14%17.5 | 38 | 54 | Semrush API + MCP +16 |
| Payments & pricing | 10%12.5 | 20 | 17 | Moz API +3 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 28 | 57 | Semrush API + MCP +29 |
| Transparency & trust | 7%8.8 | 59 | 67 | Semrush API + MCP +8 |
| Negative events | ≤15 | 0 | 0 | |
| Total | 45.3 · E | 53.1 · D |
Facts side by side
| Fact | Moz API | Semrush API + MCP |
|---|---|---|
| Kind | HTTP API | HTTP API |
| Vendor | SEOmoz, Inc. | Semrush Inc. (an Adobe company) |
| Hosted endpoint | https://api.moz.com/jsonrpc | https://api.semrush.com |
| Transports | HTTP, Streamable HTTP | HTTP, Streamable HTTP |
| Auth | API key | OAuth or key |
| Pricing | Freemium | Paid |
| x402 | no | no |
| Licence | Proprietary service under the Moz API General Conditions (effective 12 August 2026 for new subscribers). Displaying Moz data to others requires attribution under the API legal page | Proprietary service under the Semrush terms of service |
| Tools exposed | none | 14 |
| Read-only variant documented | no | yes |
| llms.txt | no | yes |
| Last release | 2026-08-14 | 2026-09-04 |
| Terms last updated | 2026-08-12 | 2026-08-25 |
| Privacy policy last updated | 2025-04-08 | 2025-10-13 |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | not found in the text | yes |
| Terms restrict benchmarking | yes | yes |
| Terms or service can change without notice | yes | not found in the text |
| Arbitration or class-action waiver | yes | yes |
Verdicts
Moz API
The JSON-RPC API documents every error code, its rate limits and the row cost of each method, and failed validation uses no quota. No working status page, SLA, machine-readable spec or official SDK was found. Tokens carry no scopes, and the free plan needs a credit card.
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
Moz API
- Send a request
idof at least 24 characters (letters, numbers and hyphens). A UUID works. Shorter ids are rejected with -32654. - Stop on a 401. Ten 401 or 403 responses in five minutes block the caller for 30 minutes.
- On 429 with code -32658 wait the
Retry-Afterseconds. On code -32650 no wait time is given, so back off exponentially. - Call
quota.lookup(free) before large pulls. List methods charge one row per result, andlimitis capped at 50 on link lists. - Poll
async.call.lookupfordata.keyword.serp.generate, and collect the result within 20 seconds of first seeing it complete.
Semrush API + MCP
- Use the MCP server at https://mcp.semrush.com/v2/mcp where the host supports it. Call a discovery tool, then
get_report_schema, thenexecute_report - Set
limitordisplay_limiton every per-line report. A backlinks row costs 40 to 45 units and a historical keyword row 50 - Check the unit balance before large pulls. A per-line report returns only the lines the balance covers, with no error
- 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 - Stay under 10 requests a second and 10 concurrent requests per account, and retry only when
error.retryableis true
Questions
Which is better for AI agents, Moz API or Semrush API + MCP?
Semrush API + MCP scores 53.1 (D) on agent readiness against Moz API's 45.3 (E), and leads in 5 of 7 scored categories. Moz API leads on reliability.
Do Moz API and Semrush API + MCP need an API key?
Moz API needs an API key. Semrush API + MCP takes an API key or an OAuth sign-in.
Can an agent call Moz API and Semrush API + MCP without installing anything?
Yes. Moz API has a hosted endpoint at https://api.moz.com/jsonrpc and Semrush API + MCP at https://api.semrush.com.
Other comparisons with Moz API or Semrush API + MCP
Machine-readable
- This page as Markdown
/compare/moz-api-vs-semrush.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/moz-api.json·/api/v1/tools/semrush.json - From a terminal
anchor compare moz-api semrush(the CLI) - Over MCP
compare_tools {"a": "moz-api", "b": "semrush"}at/mcp, no key