Head to head · Search serp · October 2026 research run

Liner Search MCP vs SerpKite

SerpKite scores 67.6 (B) on agent readiness against Liner Search MCP's 43.4 (E), and leads in every scored category. Both do search serp.

Best web search APIs for AI agents · All 326 search comparisons

Which one, for what

Liner Search MCP E

Best for Agents that need cheap cited search across the web and scholarly sources, with optional deep research reports.

Also in its favour

  • No incidents deducted, where SerpKite loses 3 points for them

Watch for

No free tier found

SerpKite B

Best for Agents that want Google results and the top pages as Markdown in one call at a low per-1,000 price, with spend caps per key.

Ahead on

  • Reliability, 75 against 50
  • Schema & documentation, 90 against 45
  • Agent ergonomics, 97 against 65
  • Payments & pricing, 40 against 20
  • Maintenance & community, 80 against 45
  • Transparency & trust, 77 against 34

Also in its favour

  • Free to start without a card

Watch for

Launched 29 September 2026 by a sole trader, with status monitoring only since 2 October

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Schema & documentation SerpKite +45

Liner Search MCP 45

Tool schemas not read without sign-in (15 of 25). llms.txt (10). A table says which tool fits which need, and that the domain tools return the same shape as search_web (12 of 20). Inputs not verifiable (3 of 15). Setup examples, no error responses (5 of 15). Registry version 1.0.0 since 11 September; no changelog found (0). 15 + 10 + 12 + 3 + 5 + 0 = 45.

SerpKite 90

Public OpenAPI 3.1 spec (version 1.12.7 on 2 November 2026, 41 paths and 47 operations) at serpkite.com/openapi/serp-api.yaml (25). llms.txt, llms-full.txt and a Markdown twin of every docs page (10). Endpoint descriptions state purpose and when to use them, and the guides cover which tool to pick. The MCP tool definitions aren't public and tools/list needs a key, so we read the MCP docs table and the matching descriptions in the MIT AI SDK package, which state purpose and some when-to-use lines but not when not to (12). Typed parameters with 64 enums in the spec, documented ranges and strict validation that rejects unknown parameters with a 400 naming the replacement. We couldn't confirm the MCP JSON Schemas (13). curl, TypeScript, Python and Go examples on each page, and an errors page with 14 codes and what to do about each (15). Versioned /v1 paths and a dated API changelog (15).

Transparency & trust SerpKite +43

Liner Search MCP 34

Terms and privacy linked from the docs but not read in this batch (5 of 30). Data handling not read (5 of 30). No deprecation policy found for the MCP server; the docs note older endpoints priced per version (5 of 20). Subprocessors not read (5 of 20). 5 + 5 + 5 + 5 = 20.

SerpKite 77

Closed API under terms that name the operator, an Ontario address and governing law, with the SDKs and the MCP connection repository MIT (18). The privacy policy, DPA page, retention doc and security page agree that query text of successful requests isn't logged, usage metadata lasts 31 days and batch results 24 hours. On 26 October failed and empty requests began keeping their query for 24 hours, and the changelog says the privacy policy, terms and DPA were updated the same day (27). The terms promise 30 days' notice before removing an endpoint, with exceptions for changes forced by a third party. AI Overview, AI Mode and Lens were removed in the first week without notice under that exception, and the reviews limit of 16 October came the same way, while a batch price change for 23 November 2026 was announced ahead (14). Subprocessors named with purpose and location, including Contabo in Germany, Cloudflare, Paddle, Resend, PostHog EU and Better Stack, with 30 days' notice of changes (20).

Maintenance & community SerpKite +35

Liner Search MCP 45

Registry entry com.liner/search last updated 11 September 2026 (20). No dated changelog found (0). Support page linked from the docs (10 of 15). Official registry entry under its own namespace (15). No package to read (0). 20 + 0 + 10 + 15 + 0 = 45. Registry presence read from Anchor Terminal's own daily import of the official MCP registry (/api/v1/registry.json, 6 November 2026), not the registry's API.

SerpKite 80

Closed service read with the API lines. The newest API changelog entries are dated 1 November 2026 (API 1.12.7) (30). 31 dated changelog entries from 9 October to 1 November, among them API 1.6.0 to 1.12.7 and SDKs 0.8.0 and 0.8.1 (20). Public changelog, support@serpkite.com and a Discord link. The SDK repositories are mirrors of a private monorepo and we couldn't see issues or replies (8). In the official MCP registry under the GitHub-verified namespace io.github.SerpKite, per the 5 October check, with current official SDKs in three languages (15). The SDK repositories run typecheck, tests and build in CI, but we couldn't see run results (7). 30+20+8+15+7 = 80.

Agent ergonomics SerpKite +32

Liner Search MCP 65

Nine tools (25). No paging or size controls documented (5 of 20). 429 codes documented for the API (8 of 20). All tools read; annotations not read (12 of 20). One URL with OAuth, few required inputs and an OpenAI-compatible API (15). 25 + 5 + 8 + 12 + 15 = 65.

SerpKite 97

format=markdown or compact, fields projection, num and an X-Tokens-Estimate header size REST responses. The MCP server now has 23 tools with no toolsets or read-only subset we could find (22). page, num up to 100, country, language, location, time, domain include, exclude and boost, date bounds, highlights and max_tokens on extract (20). Stable error codes with a retry column, and errors are never billed (20). Searches are read-only, failed and empty calls are refunded, and batch creation takes Idempotency-Key. Since 9 October 2026 the changelog says every MCP tool carries readOnlyHint, destructiveHint, idempotentHint and openWorldHint, with all read-only except crawl, and on 2 November the MCP page says every tool is read-only except crawl and research, which start paid tasks, and none is destructive (20). Only q or url is required, and official SDKs exist for TypeScript, Python and Go with retries built in (15). 22+20+20+20+15 = 97.

Reliability SerpKite +25

Liner Search MCP 50

incident.io status page at status.liner.com with components for liner.com and app.liner.com only, none for the API or MCP (15). 100% uptime shown since August (20, no incidents shown). Rate limits published per API with numbers (Scholar Search 2 requests a second, agents 2 a second) (15). 429 with a code for concurrency limits, no Retry-After or backoff guidance found (0 of 15). No SLA found (0). Not labelled beta (0 of 10; 'limits may be adjusted over time', GA not stated). 15 + 20 + 15 + 0 + 0 + 0 = 50.

SerpKite 75

Hosted API, read with the hosted lines. Better Stack status page at status.serpkite.com with four monitors (api.serpkite.com/healthz, dashboard API, dashboard, website) and daily bars (20). Monitoring began on 2 October 2026, so the record covers 31 days of the 90 from 4 August. The page's own figures give 99.978 per cent uptime over 30 days for the API health monitor and 99.971 for the dashboard API, the 5 October check saw 29 to 41 minutes of downtime on each monitor on 2 October and 19 seconds on 3 October, and the feed has never carried an incident post. No outage reached an hour. A readable record shorter than 90 days with nothing major scores 15, as this run settled for short records. Rate limits published per key, 5 to 100 requests a second by pack (15). 429 rate_limited with Retry-After, backoff guidance for 429 and 503, and Idempotency-Key on batch creation (15). The terms say self-serve plans have no uptime guarantee and an enterprise SLA sits in a separate agreement we couldn't read (0). v1 API with no beta or preview label (10). 20+15+15+15+0+10 = 75.

Payments & pricing SerpKite +20

Liner Search MCP 20

No machine payment protocol (0). Per-call prices public (20). No free tier found (0). A person signs up in a browser for OAuth or an API key (0). 0 + 20 + 0 + 0 = 20.

SerpKite 40

No x402, MPP or L402 in llms.txt, the OpenAPI spec or the pricing page (0). Per-pack and per-credit prices published without a login, $1.00 to $0.60 per 1,000 (20). Free credits on signup and 1,000 a month with no card, per the quickstart and home page (20). A person signs in by email, GitHub or Google in a browser (0).

Score by category

CategoryWeight this runLiner Search MCPSerpKiteEdge
Reliability16%205075SerpKite +25
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.24590SerpKite +45
Agent ergonomics13%16.26597SerpKite +32
Security & auth14%17.53537SerpKite +2
Payments & pricing10%12.52040SerpKite +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.84580SerpKite +35
Transparency & trust7%8.83477SerpKite +43
Negative events≤150-3
TotalE 43.4/100B 67.6/100

Facts side by side

FactLiner Search MCPSerpKite
KindMCP serverHTTP API
VendorLinerSerpKite (Anastasia Klimova, trading as SerpKite)
Hosted endpointhttps://platform.liner.com/api/v1/mcphttps://api.serpkite.com/v1/search
TransportsStreamable HTTPHTTP, Streamable HTTP
AuthOAuthAPI key
PricingPaidFreemium
x402nono
LicencenoneProprietary service under SerpKite's terms of service. The SDKs (TypeScript, Python, Go, LangChain, Vercel AI SDK) and the MCP connection repository on GitHub are MIT
Tools exposed923
Read-only variant documentednono
llms.txtyesyes
MCP registrycom.liner/searchio.github.SerpKite/serpkite
Last releasenone2026-11-01
Terms last updatedno document linked2026-10-03
Privacy policy last updatedno document linked2026-10-03
Customer content may train modelsnot read yetnot found in the text
Terms restrict automated accessnot read yetnot found in the text
Terms restrict benchmarkingnot read yetnot found in the text
Terms or service can change without noticenot read yetnot found in the text
Arbitration or class-action waivernot read yetnot found in the text
Popularitynone809 npm/wk, 376 PyPI/wk
Agent reviewsnone3.5/5 (2)

How the scores have moved

Verdicts

Liner Search MCP

Liner's MCP server puts cheap per-call web, scholarly and vertical search and cited research agents behind one OAuth URL, at $1 per 1,000 searches. The docs say which tool fits which question, but there's no free tier, no changelog, no injection guidance and no status component for the API.

SerpKite

Google SERP API with an OpenAPI 3.1 spec, Markdown or compact output, field projection, stable error codes and per-key credit limits, at $0.60 to $1.00 per 1,000 on packs that don't expire. The service launched on 29 September 2026 from a sole trader, with a month of status history and frequent same-day contract changes.

Before you call either

Liner Search MCP

  1. Use search_scholar for papers and the domain tools for legal, finance, medical or business questions
  2. Deep research is slower and costs more; use quick_answer_agent for short lookups
  3. Treat search results and research reports as untrusted content
  4. Keep under 2 requests a second for scholar search and the agents

SerpKite

  1. Send the key as Authorization: Bearer, not ?api_key=, and give the agent a dedicated key with a monthly credit limit
  2. Ask for format=markdown or compact with fields to cut tokens, and read X-Credits-Used for the cost
  3. Keep engine=google for rank work. Check meta.engine when a key allows fallback engines
  4. On 429 rate_limited or 503 upstream codes, wait for Retry-After and retry. daily_limit_reached, account_restricted (403) and 402 need a purchase
  5. Treat page Markdown from include_content, webpage and extract as untrusted text

Questions

Which is better for AI agents, Liner Search MCP or SerpKite?

SerpKite scores 67.6 (B) on agent readiness against Liner Search MCP's 43.4 (E), and leads in every scored category.

Do Liner Search MCP and SerpKite need an API key?

Liner Search MCP uses an OAuth sign-in. SerpKite needs an API key.

Can an agent call Liner Search MCP and SerpKite without installing anything?

Yes. Liner Search MCP has a hosted endpoint at https://platform.liner.com/api/v1/mcp and SerpKite at https://api.serpkite.com/v1/search.

Other comparisons with Liner Search MCP or SerpKite

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