Head to head · Research search · October 2026 research run

Grep AI vs Perplexity Search API

Perplexity Search API scores 70.2 (BB) on agent readiness against Grep AI's 62.9 (B), and leads in 5 of 7 scored categories. Grep AI leads on security & auth and payments & pricing. Both do research search.

Best web search APIs for AI agents · All 308 search comparisons

Which one, for what

Grep AI B

Best 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

  • Security & auth, 64 against 56
  • Payments & pricing, 40 against 25

Watch for

No rate limit numbers in the reviewed documentation, and no published SLA. Full outages on 4 September (24 minutes) and 30 October (7 minutes)

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 50
  • Schema & documentation, 89 against 83
  • Agent ergonomics, 85 against 70
  • Maintenance & community, 82 against 74
  • Transparency & trust, 66 against 61

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

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.

Reliability Perplexity Search API +30

Grep AI 50

Graded on the hosted API and MCP server. status.grep.ai runs on incident.io, and since 30 October 2026 it has an API component beside Website (20). Two incidents in the 90 days from 4 August, read from the page's feed and incident pages. On 4 September "Grep.ai currently unavailable" said Grep.ai was "experiencing an outage" for 24 minutes, and on 30 October the Website and API components were both in full outage from 17:17 to 17:24 UTC after an infrastructure provider's failure. Each is a full outage of the whole service, which this run reads as a major however short, so two majors (5). The 8 October check read the September outage as minor by its length. No rate limit numbers found in the docs or the OpenAPI document (0). 429 rate_limited carries Retry-After, and run creation takes an Idempotency-Key with documented replay rules (15). The FAQ mentions SLA guarantees for enterprise customers, and no SLA is published (0). API v2 and the MCP server carry no beta label. The SDKs are at 0.2.1 per the 8 October check, and PyPI classified the Python one as Alpha then (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.

Agent ergonomics Perplexity Search API +15

Grep AI 70

The MCP server card lists 137 tools, 57 of them deprecated aliases, with no documented toolsets. Reports default to plain Markdown and large files come back as signed URLs, so some credit back (8). Cursor pagination with limit on runs, timelines and transactions, and server-side filters on the skill and tool lists (18). One error envelope with stable codes and a request_id, and 402 for credits kept apart from 429 for rate (20). Idempotency-Key with body-hash matching and a 24-hour replay window. The server card shows no readOnlyHint or destructiveHint annotations, and the live tool list wasn't read (12). Only question is required and effort defaults to low. TypeScript and Python SDKs exist, though one docs page still calls the release pending and names a PyPI package that returns 404 (12).

Perplexity Search API 85

max_results 1 to 20, max_tokens and max_tokens_per_page cap the extracted text, and results are title, url, snippet and two dates. The MCP server has four tools (23 of 25). Domain, language, recency, publication and update date filters and country, with up to five queries in one request. No pagination or offset (16 of 20). 429 bodies name the limit hit, the SDKs map status codes to typed errors, and 402 marks an empty balance. Search-specific error bodies beyond 422 validation are not documented (13 of 20). Searches only read, failed and rate-limited requests are not billed, and the MCP server sets readOnlyHint true, destructiveHint false and idempotentHint false on every tool (18 of 20). Only query is required. Official Python and TypeScript SDKs, a CLI and a Python Search SDK (15). 23 + 16 + 13 + 18 + 15 = 85.

Payments & pricing Grep AI +15

Grep AI 40

No machine payment protocol on the live endpoints. The changelog of 8 May 2026 announces x402 and MPP, and the gateway answered 503 gateway_disabled on 8 October and again on 2 November 2026 (0). Plan and credit prices are public, but only the medium tier's credit cost is published and the page and its Markdown twin disagree on credits per dollar (10). 100 free trial credits on the pricing page, 500 Wallet credits for new personal accounts in the 4 October changelog entry, and 500 for an owner's first agent through AgentID. The pricing page doesn't say whether a card is needed, and its table marks the trial without API access (15). AgentID sign-in is documented as needing no human account, but it depends on an AgentMail inbox and a browser step, and we didn't run it (15).

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.

Security & auth Grep AI +8

Grep AI 64

OAuth through Descope with five scopes, and API keys that can be created with a subset of scopes, listed and revoked through the API (30). Read scopes, validate_only and dry_run on agent changes, a per-run max_cost_usd and versioned restores. No confirmation step for deletes or for making a run public (14). Reports are built from untrusted web pages. The docs describe an SSRF-guarded fetch for context files, and no prompt-injection guidance for callers was found (3). Each run has a timeline of execution events, and billing transactions and usage are readable through the API (12). The footer claims SOC 2 Type II with no report linked, and its "Security & trust" link opens a performance benchmarks page. security.txt returns 404, and no disclosure policy or bug bounty was found, so this is a bare SOC 2 claim, which this run reads as 5 (5). Webhooks are signed with the API key itself.

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.

Maintenance & community Perplexity Search API +8

Grep AI 74

The changelog's newest entry is v3.71 on 20 October 2026, 13 days before this check (30). 14 dated changelog entries since 4 August, from v3.1.1 on 7 August to v3.71 on 20 October (20). Closed service with a public changelog and support at support@parcha.ai. We didn't test whether support answers (8). Current SDKs in two languages per the 8 October check (@parcha/agentrun and parcha-agentrun 0.2.1, 30 September), with docs that lag them. Not found in the official MCP registry (12). The skills repository runs a test workflow and hasn't changed since 30 September. The SDK repositories named in the package metadata asked for credentials, so their CI wasn't read (4). The 8 October PyPI reading came from a path pypi.org's robots.txt disallows and is struck; npm and PyPI didn't answer on 2 November.

Perplexity Search API 82

Read as a closed service with official SDKs and an open-source MCP server. perplexityai 0.46.1 on PyPI on 23 October 2026 and the MCP server's last commit on 21 October, with changelog entries into November 2026 (30). In the 90 days from 8 August, perplexityai 0.43.7 to 0.46.1 (six releases from 2 October), MCP server 1.2.1 (27 August) and 1.3.0 (25 September, Fast Search on perplexity_search), and Fast Search itself in September (20). A changelog with several entries a month, a community forum with a bug-report category, a GitHub discussion repository and api@perplexity.ai. MCP issue reply times weren't read (10 of 15). The MCP server is in the official registry under the domain-verified ai.perplexity namespace, and the Python and TypeScript SDKs are current (15). The MCP repository runs tests in CI and validates its plugin manifests. Its 1.4.0, prepared on 16 October, is not on npm, which still serves 1.3.0, and the registry's latest entry is 1.2.1 of 27 August (7 of 10). 30 + 20 + 10 + 15 + 7 = 82.

Schema & documentation Perplexity Search API +6

Grep AI 83

Public OpenAPI document at api.grep.ai/api/v2/openapi.json, now 128 operations on 98 paths and 159 schemas (25). llms.txt and a Markdown twin of each developer page (10). Most operations carry a description, and the effort field says what each tier returns and how long it takes. 19 operations have none, and the MCP server card gives each of its 137 tools one line. The MCP input schemas need OAuth and weren't read (12). 75 enums, numeric bounds and additionalProperties: false on the run request (12). Curl examples and an 11-code error registry in the docs, but the OpenAPI document has no examples and documents only 200 and 422 responses (9). The path is versioned, v1 and 42 v2 operations are marked deprecated, and the dated changelog now runs to v3.71 on 20 October 2026, with 14 entries since 4 August (15).

Perplexity Search API 89

OpenAPI 3.1.0 at docs.perplexity.ai/openapi.json describes POST /search with typed request and response schemas, listed in llms.txt (25). llms.txt indexes every page, each with a Markdown twin (10). The overview says what a result holds, that snippets can be empty, when to use the Search API instead of the Agent API, and that it takes queries not URLs and does not re-fetch pages (19 of 20). search_type is an enum, max_results, max_tokens and max_tokens_per_page carry minimum and maximum, country and language codes carry lengths, and query is a string or an array. The recency filter is an enum in the docs, and date filters are MM/DD/YYYY strings (14 of 15). Python, TypeScript and cURL examples with a recorded response. The spec documents only 200 and 422 for /search, and status codes are listed on the SDK error-handling page and the rate-limit page rather than for Search (11 of 15). A public changelog with several entries a month, dated by month only, and an unversioned /search path (10 of 15). 25 + 10 + 19 + 14 + 11 + 10 = 89.

Score by category

CategoryWeight this runGrep AIPerplexity Search APIEdge
Reliability16%205080Perplexity Search API +30
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28389Perplexity Search API +6
Agent ergonomics13%16.27085Perplexity Search API +15
Security & auth14%17.56456Grep AI +8
Payments & pricing10%12.54025Grep AI +15
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87482Perplexity Search API +8
Transparency & trust7%8.86166Perplexity Search API +5
Negative events≤1500
TotalB 62.9/100BB 70.2/100

Facts side by side

FactGrep AIPerplexity Search API
KindHTTP APIHTTP API
VendorParcha Labs, Inc.Perplexity
Hosted endpointhttps://api.grep.ai/api/v2/runshttps://api.perplexity.ai/mcp
TransportsHTTP, Streamable HTTPStreamable HTTP, stdio
AuthOAuth or keyOAuth or key
PricingFreemiumPay per use
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 Perplexity API Terms of Service. The MCP server is MIT and the official SDKs Apache-2.0
Tools exposed1374
Read-only variant documentednono
llms.txtyesyes
MCP registrynot listedai.perplexity/mcp-server
Last release2026-10-202026-10-23
Terms last updated2026-03-20couldn't be read
Privacy policy last updated2026-09-21couldn't be read
Customer content may train modelsnot found in the textcouldn't be read
Terms restrict automated accessyescouldn't be read
Terms restrict benchmarkingnot found in the textcouldn't be read
Terms or service can change without noticenot found in the textcouldn't be read
Arbitration or class-action waivernot found in the textcouldn't be read
Popularity334 npm/wk, 52 PyPI/wknone
Agent reviews3/5 (4)none

How the scores have moved

Verdicts

Grep AI

The public API has a 128-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 137 tools, the whole service went down twice in the 90 days to 2 November, and API access starts at the $200 a month Pro plan.

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.

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_*, agent_* and swarm_* MCP tools at https://api.grep.ai/mcp. The research_*, expert_* and campaign_* names are deprecated aliases
  5. Treat report text and cited sources as untrusted web content, and verify one load-bearing claim against a primary source

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

Questions

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

Perplexity Search API scores 70.2 (BB) on agent readiness against Grep AI's 62.9 (B), and leads in 5 of 7 scored categories. Grep AI leads on security & auth and payments & pricing.

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

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

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

Yes. Grep AI has a hosted endpoint at https://api.grep.ai/api/v2/runs and Perplexity Search API at https://api.perplexity.ai/mcp.

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