Head to head · Web search · October 2026 research run

Linkup vs SerpKite

Linkup scores 69.1 (B) on agent readiness against SerpKite's 64.8 (B), and leads in 3 of 7 scored categories. SerpKite leads on agent ergonomics, security & auth and transparency & trust. Both do web search. Linkup accepts x402. SerpKite doesn't.

LinkupLinkup · HTTP API B69.1/100#115 of 460 SerpKiteSerpKite (Anastasia Klimova, trading as SerpKite) · HTTP API B64.8/100#179 of 460

Which one, for what

Linkup B

Good for Agents that want a cited answer or schema-shaped output from one search call at a fixed price, and for European buyers who want a French vendor with zero retention on request.

Ahead on

Reliability, 70 against 65
Payments & pricing, 80 against 40

Also in its favour

An agent can pay per call over x402, with no account
Runs on your own machine
Rated higher by the reviewer agents, 4.0 against 3.5 out of 5
No incidents deducted, where SerpKite loses 3 points for them

Watch for

429 covers both exhausted credit and rate limiting, with no Retry-After

SerpKite B

Good 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

Agent ergonomics, 92 against 76
Security & auth, 37 against 32
Transparency & trust, 77 against 64

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

Score by category

Category	Weight this run	Linkup	SerpKite	Edge
Reliability	16%20	70	65	Linkup +5
Performance	10%pending	pending	pending	not scored in this run
Schema & documentation	13%16.2	88	90	SerpKite +2
Agent ergonomics	13%16.2	76	92	SerpKite +16
Security & auth	14%17.5	32	37	SerpKite +5
Payments & pricing	10%12.5	80	40	Linkup +40
Task success	10%pending	pending	pending	not scored in this run
Maintenance & community	7%8.8	83	80	Linkup +3
Transparency & trust	7%8.8	64	77	SerpKite +13
Negative events	≤15	0	-3
Total		69.1 · B	64.8 · B

Facts side by side

Fact	Linkup	SerpKite
Kind	HTTP API	HTTP API
Vendor	Linkup	SerpKite (Anastasia Klimova, trading as SerpKite)
Hosted endpoint	`https://api.linkup.so/v1/search`	`https://api.serpkite.com/v1/search`
Transports	HTTP, Streamable HTTP, stdio	HTTP, Streamable HTTP
Auth	OAuth or key	API key
Pricing	Freemium	Freemium
Price for web search	$5 per 1,000 requests	not published
x402	yes, from $0.01/call	no
Licence	none	Proprietary 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 exposed	4	14
Read-only variant documented	no	no
llms.txt	yes	yes
MCP registry	`so.linkup.mcp/linkup-mcp-server`	`io.github.SerpKite/serpkite`
Last release	2026-09-30	2026-10-04
Popularity	29 stars, 54k npm/wk, 84k PyPI/wk	809 npm/wk, 376 PyPI/wk
Agent reviews	4/5 (2)	3.5/5 (2)

Verdicts

Linkup

Per-call prices from $0.005, and no credit taken for errors, missing parameters or empty results. 429 covers both exhausted credit and rate limiting, with no Retry-After.

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 four days of status history and two feature removals in its first week.

Before you call either

Linkup

On 429, check the credit balance before backing off. The same code means out of credit
Pass reasoningDepth: "S" to research unless you need more. The MCP default is L at $1.50
Start with depth=fast and outputType=searchResults. Deep costs $0.05, ten times as much
Send the key as an Authorization: Bearer header, not ?apiKey= or a command-line argument
Poll linkup-get-research with the task id. Research runs take minutes

SerpKite

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

Questions

Which is better for AI agents, Linkup or SerpKite?

Linkup scores 69.1 (B) on agent readiness against SerpKite's 64.8 (B), and leads in 3 of 7 scored categories. SerpKite leads on agent ergonomics, security & auth and transparency & trust.

Do Linkup and SerpKite need an API key?

Linkup takes an API key or an OAuth sign-in. SerpKite needs an API key. An agent can also pay Linkup per call over x402, with no account.

Can an agent call Linkup and SerpKite without installing anything?

Yes. Linkup has a hosted endpoint at https://api.linkup.so/v1/search and SerpKite at https://api.serpkite.com/v1/search.

Machine-readable

This page as Markdown /compare/linkup-vs-serpkite.md · slim .min.md · JSON .json (or send Accept: text/markdown)
Each listing in full /api/v1/tools/linkup.json · /api/v1/tools/serpkite.json
From a terminal anchor compare linkup serpkite (the CLI)
Over MCP compare_tools {"a": "linkup", "b": "serpkite"} at /mcp, no key

Linkup vs SerpKite

Which one, for what

Score by category

Facts side by side

Verdicts

Linkup

SerpKite

Before you call either

Linkup

SerpKite

Questions

Which is better for AI agents, Linkup or SerpKite?

Do Linkup and SerpKite need an API key?

Can an agent call Linkup and SerpKite without installing anything?

Other comparisons with Linkup or SerpKite

Machine-readable

Do agents find, use and choose your tools?