Head to head · Web search · October 2026 research run

Perplexity Search API vs Valyu

Perplexity Search API and Valyu score within a point of each other on agent readiness, 70.2 (BB) and 69.3 (B). Valyu leads on payments & pricing and transparency & trust. Both do web search.

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

Which one, for what

Perplexity Search API BB

Best for Agents on any model that need raw ranked sources with extracted text at a low per-request price, and teams that want cited answers from the same key through the Agent API.

Ahead on

  • Reliability, 80 against 70
  • Security & auth, 56 against 44

Also in its favour

  • Agent-ready, a grade of BB or better
  • Runs on your own machine

Watch for

The FAQ says uptime and recovery time are not guaranteed, and the terms carry no SLA

Valyu B

Best for Research agents that need SEC filings, papers, patents, clinical trials or market data alongside the web, with a per-query price cap.

Ahead on

  • Payments & pricing, 45 against 25
  • Transparency & trust, 78 against 66

Watch for

Per-plan rate limits are stated only in example responses, not in a table

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 Valyu +20

Perplexity Search API 25

No x402, MPP or L402 in the docs, pricing page, OpenAPI or llms.txt (0). $5 per 1,000 successful requests, $1 with Fast Search, published without a login, with failed and rate-limited requests not billed (20). Usage is prepaid with a card on the billing page, and no free allowance was found. The console playground needs no key but is a page for a person, not an API allowance (0). A person signs up in the console. The Stripe Projects route provisions a project, key and credits from a terminal, but needs a person's Stripe account with a payment method and a $10 minimum purchase (5 of 20, as on the Decisions API listing). 0 + 20 + 0 + 5 = 25.

Valyu 45

No x402, MPP or L402 in llms.txt, the pricing page or the OpenAPI file on 2 November, so there was no payment route to check live (0). Since October usage is billed in credits, 1,600 for a $10 top-up, with per-result Search prices by source (web and news 0.1 credits, arXiv and PubMed 0.05, SEC filings 1.92), Contents at 0.2 a URL and fixed DeepResearch prices by mode, all public (20). $10 of free credit ($20 with a company email), no card, valid 12 months (20). A person has to create the account, but after that an agent can log in through the CLI, headless if needed, and mint its own spend-capped keys. That's a programmatic key route after a human signup, so we gave part of the line (5). 0+20+20+5 = 45.

Security & auth Perplexity Search API +12

Perplexity Search API 56

Project API keys, shown once, revocable, and generated and revoked through two documented endpoints with a rotation guide. No per-key scopes or spending limits were found. The hosted MCP server also takes Sign in with Perplexity (OAuth). Keys go in the Authorization header only (22 of 30, as on the Decisions API listing). Search only reads, and MCP clients can disable tools, but any key reaches every API on the account, including the Agent API's sandbox and MCP tools (8 of 20). Snippets are third-party page text, and no guidance on treating them as untrusted was found in the docs, the MCP server or its SECURITY.md (0 of 15). Responses carry a request id, and the console shows usage by key. The Audit API covers enterprise organisations' web app events with its own keys, not API calls (8 of 15). security.txt valid until 31 December 2027 linking a security page, a SOC 2 Type II report, a 2025 HIPAA gap assessment and a CAIQlite listed on the trust centre, and a SECURITY.md on the MCP server that takes private reports through GitHub advisories or security@perplexity.ai. The trust centre is drawn by script and wasn't read (18 of 20). 22 + 8 + 0 + 8 + 18 = 56.

Valyu 44

The CLI mints API keys with a hard spending cap and can rotate and revoke them, management keys carry explicit scopes, organisations have MFA, and the hosted MCP has OAuth sign-in (28). The MCP docs lead with ?valyuApiKey= in the URL (minus 10). Spend-capped keys and max_price limit cost exposure, but valyu_deepresearch_control deletes tasks with no confirmation we could find (12). Search and Contents return full page text from the open web, and we found no prompt-injection guidance in the docs index (0). No per-call log or audit trail found for the operator (0). SOC 2 Type 2 shown on the privacy page and stated on the pricing page, a valid security.txt (security@valyu.ai, expires 10 March 2027, re-read on 2 November), no bug bounty or public advisories found (14). The MCP docs still give ?valyuApiKey= for every client on 2 November. 28-10+12+0+0+14 = 44.

Transparency & trust Valyu +12

Perplexity Search API 66

Closed service under terms naming Perplexity AI, Inc. and California law. The MCP server is MIT and the SDKs Apache-2.0 (18 of 30). The terms and DPA say Customer Content and personal data don't train Perplexity's models, the DPA deletes personal data within 30 days of the service ending, and the Privacy and Security page says retention varies by API and zero data retention is not the default. The DPA also says Perplexity Search may follow different data terms, which weren't found, and no retention period for search queries is stated (15 of 30). Sonar Chat Completions support ended on 27 September 2026 with a migration guide and requests reformulated rather than refused, and sonar-reasoning was removed on 15 December 2025 with a named replacement. Notices are dated by month and there is no standing notice period beyond the terms' 30 days for termination (10 of 20). A sub-processor list on the trust centre, which is drawn by script and wasn't read, ten business days' notice of new non-model subprocessors, and SCCs for EU and UK transfers. No data location is stated (8 of 20). 18 + 15 + 10 + 8 = 51.

Valyu 78

Closed service with terms that name Valyu.Network Ltd, company 14436543 in England and Wales, per the 30 September check (15). The privacy policy (20 October 2025) says queries are deleted within 24 to 72 hours, security logs kept 90 days, performance logs 30 days and billing records 7 years, and that query data isn't used to train models. No DPA referenced (26). Dated notice for the legacy MCP tools, hidden now and removed on 1 December 2026, but no general deprecation policy (12). Processing in the UK, EU and US is disclosed. Subprocessors are named by category only (12). The privacy policy is unchanged on 2 November (last updated 20 October 2025), and the pricing page now lists zero data retention on request for Enterprise. 15+26+12+12 = 65.

Reliability Perplexity Search API +10

Perplexity Search API 80

Graded on the hosted lines, for POST /search and the hosted MCP server. status.perplexity.com, on incident.io since 10 September 2026, has an API component with an RSS feed and a JSON summary. There is no separate Search component (20). In the 90 days from 8 August the feed lists 'Investigating API issue' on 13 August, resolved with no detail, a usage-based billing issue on 3 September, and on 9 October elevated errors on the website, app and Computer, where the API 'remained operational throughout'. Minor only, with the caveat that history before the migration may be incomplete (20). The Search API is limited to 50 query units a second with a burst of 50 on every tier, and the other APIs publish QPS and token limits per tier (15). 429 carries Retry-After and an error.type, the SDKs retry 429 and 5xx twice honouring Retry-After, the Search best-practices page shows backoff, and failed or rate-limited searches are not billed. Searches have no side effects (15). The FAQ says Perplexity does not guarantee uptime, failure frequency or recovery time, and the terms carry no SLA (0). No beta label on the Search API, launched on 25 September 2025 (10). 20 + 20 + 15 + 15 + 0 + 10 = 80.

Valyu 70

Instatus page at status.valyu.ai with separate Search, Contents, Answer and DeepResearch components and an RSS history (20). In the 90 days to 2 November it lists a 13-minute Search incident on 6 October with "certain data sources", a partial incident, plus scheduled maintenance on 9 August (Search, 3 hours 13 minutes, announced the evening before) and 20 October (every component, 3 hours, announced 47 minutes ahead). Minor only (20). Since 21 October limits apply per organisation and per endpoint and scale with the plan, but the numbers appear only in example responses (Search at 5 requests a second on pay-as-you-go and 10 on Ridiculously Cheap; DeepResearch at 2 and 5 tasks at once), and the pricing page the docs point to for each plan's rate doesn't list them (8 of 15). A 429 carries a Retry-After header and a body with retry_after, the plan and the limit, the docs say to wait and retry with backoff and that a rate-limited request is never charged, and the SDKs retry 429s on their own. No idempotency keys, but the pricing page says to persist research task ids so retries don't create duplicate tasks (12). No SLA found (0). Search, Contents, Answer and DeepResearch are GA, and Workflows is labelled beta (10). 20+20+8+12+0+10 = 70.

Score by category

CategoryWeight this runPerplexity Search APIValyuEdge
Reliability16%208070Perplexity Search API +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28990Valyu +1
Agent ergonomics13%16.28583Perplexity Search API +2
Security & auth14%17.55644Perplexity Search API +12
Payments & pricing10%12.52545Valyu +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88280Perplexity Search API +2
Transparency & trust7%8.86678Valyu +12
Negative events≤1500
TotalBB 70.2/100B 69.3/100

Facts side by side

FactPerplexity Search APIValyu
KindHTTP APIHTTP API
VendorPerplexityValyu
Hosted endpointhttps://api.perplexity.ai/mcphttps://api.valyu.ai/v1/search
TransportsStreamable HTTP, stdioHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingPay per useFreemium
Price for web search$2.50 per 1,000 tool calls$0.625 per 1,000 pages
x402nono
LicenceProprietary service under the Perplexity API Terms of Service. The MCP server is MIT and the official SDKs Apache-2.0none
Tools exposed46
Read-only variant documentednono
llms.txtyesyes
MCP registryai.perplexity/mcp-servernot listed
Last release2026-10-232026-10-31
Terms last updatedcouldn't be read2025-10-20
Privacy policy last updatedcouldn't be read2025-10-20
Customer content may train modelscouldn't be readnot found in the text
Terms restrict automated accesscouldn't be readnot found in the text
Terms restrict benchmarkingcouldn't be readnot found in the text
Terms or service can change without noticecouldn't be readnot found in the text
Arbitration or class-action waivercouldn't be readnot found in the text
Popularitynone19 stars, 6.7k npm/wk, 7.1k PyPI/wk
Agent reviewsnone4.5/5 (2)

How the scores have moved

Verdicts

Perplexity Search API

Raw ranked results with token-capped page text from Perplexity's own index, $5 per 1,000 requests or $1 with Fast Search, an OpenAPI description and a hosted MCP server with read-only annotations. Uptime is not guaranteed, there is no free allowance, keys carry no scopes, and no guidance on untrusted page text was found.

Valyu

Web plus academic, financial, patent and life-science sources behind one search call, billed per result with a per-query price cap. Since 21 October rate limits scale with the plan and 429s carry Retry-After, but the per-plan numbers appear only in examples. The MCP docs still put the API key in the URL.

Before you call either

Perplexity Search API

  1. Set max_tokens_per_page and max_tokens before calling; extracted text otherwise fills the context, and the price does not change with size
  2. Skip results with an empty snippet and dedupe by url when sending a query array; each query costs one rate-limit unit
  3. Use search_type: "fast" for $1 per 1,000 when latency and cost matter more than depth
  4. On 429 wait for Retry-After, then back off; on 402 stop and ask the user to add credits
  5. Use the Search API for sources and the Agent API's web_search tool for a written answer with citations

Valyu

  1. Set max_price and max_num_results on every search to bound cost
  2. Mint a spend-capped key with the Valyu CLI rather than reusing the account's main key
  3. On a 429, wait the retry_after seconds and retry; it's never charged. The SDKs retry twice by default
  4. Store each DeepResearch task id before retrying a failed create, so a retry doesn't start and bill a second task
  5. Call valyu_search. The legacy per-vertical MCP tools stop working on 2026-12-01
  6. A 206 means some sources failed. Check which before treating results as complete

Questions

Which is better for AI agents, Perplexity Search API or Valyu?

Perplexity Search API and Valyu score within a point of each other on agent readiness, 70.2 (BB) and 69.3 (B). Valyu leads on payments & pricing and transparency & trust.

Do Perplexity Search API and Valyu need an API key?

Both take an API key or an OAuth sign-in.

Can an agent call Perplexity Search API and Valyu without installing anything?

Yes. Perplexity Search API has a hosted endpoint at https://api.perplexity.ai/mcp and Valyu at https://api.valyu.ai/v1/search.

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