Head to head · Research search · October 2026 research run

Exa API + MCP vs Liner Search MCP

Exa API + MCP scores 67.8 (B) on agent readiness against Liner Search MCP's 43.4 (E), and leads in every scored category. Both do research search. Exa API + MCP accepts x402. Liner Search MCP doesn't.

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

Which one, for what

Exa API + MCP B

Best for Agents that search in natural language and want short highlights or page text in the same call, and for keyless or wallet-paid use.

Ahead on

  • Reliability, 77 against 50
  • Schema & documentation, 86 against 45
  • Agent ergonomics, 96 against 65
  • Security & auth, 43 against 35
  • Payments & pricing, 90 against 20
  • Maintenance & community, 88 against 45
  • Transparency & trust, 61 against 34

Also in its favour

  • An agent can pay per call over x402, with no account
  • Runs on your own machine
  • Free to start without a card
  • Open source

Watch for

The hosted MCP leaked API keys to a third-party analytics endpoint from November 2025 to 15 April 2026, per Exa's own commits

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 Exa API + MCP loses 9 points for them

Watch for

No free tier found

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.

Payments & pricing Exa API + MCP +70

Exa API + MCP 90

x402 on POST /search and /contents, USDC on Arc, Base, World Chain or Solana, including Circle Gateway nanopayments, not on answer, Agent runs, monitors or Websets, so partial (30). Per-call prices published without login, $0.004 for lite (and legacy instant) to $0.015 for legacy deep-reasoning per search (20). $10 a month and a $10 onboarding bonus, and the pricing page now states "No payment method required" (20). An agent can pay by x402 with no account, and the hosted MCP works anonymously within rate limits (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.

Maintenance & community Exa API + MCP +43

Exa API + MCP 88

exa-py and exa-js 2.27.0 tagged on 30 October 2026, after 2.26.0 and the API changelog entry of 19 October (30). 14 tags of each SDK from v2.17.0 (7 August) to v2.27.0 (30 October), and changelog entries on 28 August, 24 September and 19 October (20). 13 open MCP issues and pull requests merged on 2, 6, 7 and 19 October per the 21 October check, with pull requests merged on 27 and 28 October in the clone; reply times unread because GitHub's pages refuse us (15). Official registry entry ai.exa/exa under Exa's own domain, latest 3.4.1 (published 23 September), and current Python and TypeScript SDKs (15). CI typechecks and tests the MCP server on every push. The npm package (3.4.2, 6 October, per the 21 October check) ships from a workflow without git tags, and package.json on main is still 3.4.2 on 1 November (8).

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.

Schema & documentation Exa API + MCP +41

Exa API + MCP 86

OpenAPI at exa.ai/docs/exa-spec.yaml, re-read on 21 October with the new lite type, its accepted parameters and the warnings and notices response fields, and JSON Schema inputs on every MCP tool (25). llms.txt and Markdown docs (10). web_search_exa tells the model how to phrase a query and when to follow up with web_fetch_exa, and deprecated tools name their replacement. The agent_run description on the main branch since 19 October says it isn't for a single lookup or a known URL and names the sibling tools, but that commit isn't in npm 3.4.2 and we couldn't confirm the hosted server runs it, so the line stays where it was. Nothing else says when not to use a tool (15). Inputs coerce loosely. numResults is described as 1 to 100 but the schema has no bounds, and bad numbers fall back to defaults silently. On the API, lite rejects an unsupported parameter with a 400 that names it, and ignored fields such as startCrawlDate now come back as IGNORED_FIELD warnings (10). An error-codes page and examples on every endpoint page (13). Dated changelog with deprecations, the latest entry 19 October. The MCP repository has no tags, so versions show only in package.json and the registry (13).

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.

Agent ergonomics Exa API + MCP +31

Exa API + MCP 96

On a keyless connection two tools are on by default, web_search_exa and web_fetch_exa, about 1,250 characters of descriptions between them. Since the 19 October commit on main, agent_run (about 500 characters plus a larger input schema) is also on by default when the user supplies a key, though the README still lists it as optional. ?tools= turns on web_search_advanced_exa and picks the set (25). numResults, maxCharacters, highlights instead of full text, category, domain and date filters, and in web_search_advanced_exa the lite type (20). The error-codes page lists codes, and the MCP server rewrites a 429 into a message about the free tier and keys and now passes search notices to the model. Errors reach the model as text rather than a code (16). Every tool sets readOnlyHint, destructiveHint: false and idempotentHint (false on agent_run), and the server retries transient errors twice (20). Only query is required. Python and TypeScript SDKs (15).

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.

Reliability Exa API + MCP +27

Exa API + MCP 77

Instatus page at status.exa.ai with Search API, Exa MCP, Agents API and Websets components and dated history (20). In the 90 days to 1 November, history/1 shows the Search API's 1-minute blip (16 September), a 1 hour 24 minute latency incident (18 September) and 2 hours 21 minutes of elevated latency with some failed requests (21 September), and the Agents API's 25 minutes of runs failing to start (18 September, labelled major) and 4 hours 56 minutes in which 'some agent runs may fail to start or complete' (21 to 22 September). August is per the 21 October check, not re-read on 1 November (history/2 answers 404 again), with a 10-minute Search API major outage on 14 August and a 53-minute latency incident. No notices in October or November. By this run's reading each hit one product or a subset of requests and none was an hour of a core API down, so all are minor (20, up from 10, where the 21 to 22 September Agents API incident had been counted as a major). Rate limits published per endpoint, 10 QPS search and answer, 5 QPS deep, 100 QPS contents, 5 QPS and 50 active Agent runs (15). 429 with Retry-After when available and exponential backoff advice. We found no idempotency guidance for creating Agent runs, which cost money (12). No SLA found. The pricing page lists "Enterprise SLAs" on the contract plan, with no terms published (0). Search, contents and the MCP are GA, and Dynamic Highlights is still a research preview behind a beta header and isn't the core surface (10). 20 + 20 + 15 + 12 + 0 + 10 = 77.

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.

Transparency & trust Exa API + MCP +27

Exa API + MCP 61

The MCP server is MIT and the API is closed with published terms (20). The privacy policy, still dated 29 June 2026 on 21 October, says query data is used to train and fine-tune Exa's models and states no retention period. Zero data retention needs a sales conversation, and the DPA sits in the trust centre (12). Dated deprecations in the changelog, such as the pdf, github and tweet categories on 23 July and the instant, fast and deep-reasoning search types made legacy on 19 October, with no removal dates (12). The MCP server, hosted and on npm, sends usage events to Agnost (api.agnost.ai) with no mention in the README, no opt-out flag, and no named subprocessor list in the privacy policy, unchanged on main on 21 October (0).

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.

Score by category

CategoryWeight this runExa API + MCPLiner Search MCPEdge
Reliability16%207750Exa API + MCP +27
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28645Exa API + MCP +41
Agent ergonomics13%16.29665Exa API + MCP +31
Security & auth14%17.54335Exa API + MCP +8
Payments & pricing10%12.59020Exa API + MCP +70
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88845Exa API + MCP +43
Transparency & trust7%8.86134Exa API + MCP +27
Negative events≤15-90
TotalB 67.8/100E 43.4/100

Facts side by side

FactExa API + MCPLiner Search MCP
KindMCP serverMCP server
VendorExaLiner
Hosted endpointhttps://mcp.exa.ai/mcphttps://platform.liner.com/api/v1/mcp
Transportsstdio, Streamable HTTP, HTTPStreamable HTTP
AuthOAuth or keyOAuth
PricingFreemiumPaid
x402yes, from $0.007/callno
LicenceMITnone
Tools exposed49
Read-only variant documentedyesno
llms.txtyesyes
MCP registryai.exa/exacom.liner/search
Last release2026-10-30none
Terms last updatednot read yetno document linked
Privacy policy last updated2026-06-29no document linked
Customer content may train modelsyesnot read yet
Popularity4.9k stars, 1.1M npm/wk, 1.4M PyPI/wknone
Agent reviews4.5/5 (2)none

How the scores have moved

Verdicts

Exa API + MCP

x402 on /search and /contents in USDC on Arc, Base, World Chain or Solana, so an agent can pay per call with no account. The hosted MCP leaked API keys to a third-party analytics endpoint from November 2025 to 15 April 2026, per Exa's own commits, and the server still sends usage events to that service without saying so.

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.

Before you call either

Exa API + MCP

  1. Send the key as x-api-key or a Bearer header, never ?exaApiKey= in the MCP URL
  2. Ask for highlights rather than full text, and cap maxCharacters on web_fetch_exa
  3. Request only the results you'll read. More than 10 costs extra, and x402 calls stop at 10
  4. On 429, honour Retry-After. The QPS limit is shared by every key on the team
  5. Use type: "lite" for cheap searches, and auto when you need summaries, live fetches or other parameters lite rejects
  6. Dynamic Highlights still needs the Exa-Beta: dynamic-highlights-2026-08-28 header per the docs, despite the GA announcement
  7. Set budget.maxCostDollars on agent_run, which a keyed MCP connection may now expose by default

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

Questions

Which is better for AI agents, Exa API + MCP or Liner Search MCP?

Exa API + MCP scores 67.8 (B) on agent readiness against Liner Search MCP's 43.4 (E), and leads in every scored category.

Do Exa API + MCP and Liner Search MCP need an API key?

Exa API + MCP takes an API key or an OAuth sign-in. Liner Search MCP uses an OAuth sign-in. An agent can also pay Exa API + MCP per call over x402, with no account.

Can an agent call Exa API + MCP and Liner Search MCP without installing anything?

Yes. Exa API + MCP has a hosted endpoint at https://mcp.exa.ai/mcp and Liner Search MCP at https://platform.liner.com/api/v1/mcp.

Are Exa API + MCP and Liner Search MCP open source?

Exa API + MCP is open source (MIT). No open-source release is listed for Liner Search MCP.

Other comparisons with Exa API + MCP or Liner Search MCP

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