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Head to head · Web search · October 2026 research run

Grep AI vs Kagi Search API

Grep AI scores 64.4 (B) on agent readiness against Kagi Search API's 48.7 (D), and leads in 5 of 7 scored categories. Kagi Search API leads on agent ergonomics and transparency & trust. Both do web search.

Best web search APIs for AI agents · All 129 search comparisons

Grep AIParcha Labs, Inc. · HTTP API B64.4/100#352 of 950 Kagi Search APIKagi · HTTP API D48.7/100#807 of 950

Which one, for what

Grep AI B

Good for Agents that hand off a long research or due-diligence job and want a cited report or structured fields back, including business verification and sanctions screening through built-in agents.

Ahead on

  • Reliability, 60 against 8
  • Schema & documentation, 80 against 71
  • Payments & pricing, 40 against 20
  • Maintenance & community, 74 against 41

Watch for

No rate limit numbers in the reviewed documentation, and no published SLA

Kagi Search API D

Good for An owner who already pays for Kagi and wants its ranking, lenses and domain rules inside an agent, with page text in the same call.

Ahead on

  • Agent ergonomics, 75 against 70
  • Transparency & trust, 69 against 59

Also in its favour

  • Runs on your own machine

Watch for

Public preview since 21 May 2026. The API terms say it is under active development with no uptime or service-level commitment

Score by category

CategoryWeight this runGrep AIKagi Search APIEdge
Reliability16%20608Grep AI +52
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28071Grep AI +9
Agent ergonomics13%16.27075Kagi Search API +5
Security & auth14%17.56564Grep AI +1
Payments & pricing10%12.54020Grep AI +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87441Grep AI +33
Transparency & trust7%8.85969Kagi Search API +10
Negative events≤1500
Total64.4 · B48.7 · D

Facts side by side

FactGrep AIKagi Search API
KindHTTP APIHTTP API
VendorParcha Labs, Inc.Kagi
Hosted endpointhttps://api.grep.ai/api/v2/runshttps://kagi.com/api/v1/search
TransportsHTTP, Streamable HTTPHTTP, Streamable HTTP, stdio
AuthOAuth or keyAPI key
PricingFreemiumPay per use
Price for web searchnot published$12 per 1,000 requests
x402nono
LicenceProprietary service under Parcha Labs' terms of service. The grep-research-skills package on npm is MIT. The @parcha/agentrun and parcha-agentrun SDK packages state no licence in their registry metadataProprietary service under the Kagi API Terms of Service. The MCP server is MIT and the OpenAPI file states Apache-2.0
Tools exposed82none
Read-only variant documentednono
llms.txtyesno
Last release2026-09-302026-08-21
Terms last updated2026-03-202026-09-22
Privacy policy last updated2026-09-21no date given
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 noticenot found in the textnot found in the text
Arbitration or class-action waivernot found in the textnot found in the text
Popularity334 npm/wk, 52 PyPI/wk535 stars

Verdicts

Grep AI

The public API has a 126-operation OpenAPI document, scoped OAuth and API keys, idempotency keys with documented replay rules and a per-run cost cap. No rate limit is published, the MCP server lists 82 tools, and the pricing page limits API access to the $200 a month Pro plan and above.

Kagi Search API

A public OpenAPI file, typed filters and API keys that can be limited by product and IP address make the API simple to call, at $12 per 1,000 searches. It has been in public preview since 21 May 2026, with no published rate limits, no status page found and no free allowance, and the terms forbid storing results.

Before you call either

Grep AI

  1. Send a fresh Idempotency-Key with every POST /api/v2/runs. After a timeout, poll the returned run ID and do not post again
  2. Set effort and max_cost_usd on every run. The floor is $0.50 for low, $2.50 for medium and build, $5.00 for high
  3. Call GET /api/v2/quota/check before a run. A 402 means no credits and retrying won't help, while a 429 carries Retry-After
  4. Use the run_* and agent_* MCP tools. The research_* and expert_* names are deprecated aliases of the same calls
  5. Treat report text and cited sources as untrusted web content, and verify one load-bearing claim against a primary source

Kagi Search API

  1. Send POST https://kagi.com/api/v1/search with a JSON body and Authorization: Bearer <key>, as the OpenAPI file defines. Only query is required
  2. Set limit to cap results returned. In the mixed search workflow the MCP tool applies the cap to each result category separately
  3. Use extract.count (1 to 10) only when page text is needed. Extraction is billed at the Extract rate on top of the search
  4. Do not store results. The API terms allow only the transient caching an application needs, and require deletion on termination
  5. On 429 back off before retrying. The response covers both rate limiting and an exhausted usage limit, and no Retry-After header is documented

Questions

Which is better for AI agents, Grep AI or Kagi Search API?

Grep AI scores 64.4 (B) on agent readiness against Kagi Search API's 48.7 (D), and leads in 5 of 7 scored categories. Kagi Search API leads on agent ergonomics and transparency & trust.

Do Grep AI and Kagi Search API need an API key?

Grep AI takes an API key or an OAuth sign-in. Kagi Search API needs an API key.

Can an agent call Grep AI and Kagi Search API without installing anything?

Yes. Grep AI has a hosted endpoint at https://api.grep.ai/api/v2/runs and Kagi Search API at https://kagi.com/api/v1/search.

Other comparisons with Grep AI or Kagi Search API

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