Head to head · Research search · October 2026 research run

SpecStream vs You.com APIs

You.com APIs scores 76.1 (BB) on agent readiness against SpecStream's 64.4 (B), and leads in 6 of 7 scored categories. SpecStream leads on security & auth. Both do research search. SpecStream accepts x402. You.com APIs doesn't.

Best web search APIs for AI agents · All 201 search comparisons

Which one, for what

SpecStream B

Best for Agents that need a list of companies, places, grants, tenders, papers or packages matching stated conditions, with a source page on every value and a price approved before anything runs, and teams that want the same list rechecked on a schedule and sent to a sheet or CRM.

Ahead on

  • Security & auth, 73 against 59

Also in its favour

  • An agent can pay per call over x402, with no account
  • No incidents deducted, where You.com APIs loses 3 points for them

Watch for

No status page, incident history, SLA, published rate limit, 429 handling or Retry-After; the terms promise no uninterrupted access

You.com APIs BB

Best for An unattended agent that needs search, page text and cited answers and wants to pay per call without an account.

Ahead on

  • Reliability, 80 against 23
  • Schema & documentation, 92 against 80
  • Agent ergonomics, 83 against 65

Also in its favour

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

Watch for

Two API hosts. Answer and Research return 'Missing Authentication Token' on ydc-index.io

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 You.com APIs +57

SpecStream 23

Hosted reading, for the MCP server and REST API on api.specstream.ai. No public status page was found. None is linked from the site, llms.txt or the docs, llms-full.txt mentions none, and https://specstream.ai/status returned an error (0). No readable incident history, so the floor (5). No rate limit with numbers is published in the docs, llms.txt, llms-full.txt or the part of the OpenAPI file read; the privacy policy and DPA mention rate limiting without figures, and the published limits are per job (10,000 results a request, four-hour runs, 20,000 imported rows) (0). Nothing documents 429, Retry-After or backoff, but paid work requires an idempotency_key on authorize_capacity_work and POST /v1/capacity/executions, GET /v1/capacity/requests/{request_key} recovers the original find after an uncertain response, and the skills say never to quote again to recover a lost reply (8 of 15). No SLA on any plan, and the terms say 'We do not promise uninterrupted access' (0). No beta or preview label on the API, the MCP server or the SDKs, which PyPI classifies as production and stable at 1.2 (10). 0+5+0+8+0+10 = 23.

You.com APIs 80

Rootly status page at status.you.com with Search/Index, Live News and AI Search API components (20). Its robots.txt loaded on 1 November, but incident pages still answered with a Cloudflare challenge, so we read the history RSS feed as before. In the 90 days to 1 November it lists one incident, an 'Authentication Outage' on the AI Search API component posted on 5 October, and nothing after it. The feed gives no duration, so we couldn't establish the outage as a major. Minor only (20). 10 requests a second per API and 5 for Finance Research on self-serve accounts, re-read on 1 November (15). 429 carries Retry-After, the docs give exponential backoff capped at 60 seconds, and X-RateLimit-* headers allow client-side throttling (15). No SLA found for the search APIs. The pricing page banner claims an uptime SLA of at least 99.9% for the new Inference Router, but we found no SLA document (0). GA (10).

Agent ergonomics You.com APIs +18

SpecStream 65

MCP reading. 128 tools at about 143,700 characters of names, descriptions and schemas (more than 30, 5), with no server-side toolsets or dynamic loading; the framework packages for LangChain, LlamaIndex, CrewAI and the Vercel AI SDK and the Open WebUI tool expose two to four tools with the price cap held in code, and results default to short evidence (5 back, 10 of 25). Cursor and limit on rows, search, specs and revisits, evidence short or full, filters by area and by field on collections, and unconfirmed candidates kept in a separate list (18 of 20). An ErrorEnvelope on every operation and an SDK error class that exposes code and details, but no published code list, meanings or retry rules (6 of 20). Required idempotency keys on paid work, schedules and refund claims with a recovery route, expected_version on updates, stable event ids on webhook retries, and readOnlyHint on 72 tools and destructiveHint on 29, with no idempotentHint (18 of 20). compile needs only q, a quote needs only ast_hash with 25 results by default, and official SDKs in Python and TypeScript with a CLI, though one purchase takes three calls with a hash carried between them (13 of 15). 10+18+6+18+13 = 65.

You.com APIs 83

Six MCP tools per the docs, which state there is no you-answer tool, with ?tools= or X-Allowed-Tools to load a subset, a default allow-list of four, and a free profile that exposes two. Web Search returns up to 100 results with extraction opt-in (25). Result count, domain include, exclude and boost lists, safesearch, and since 9 October a total_max_tokens budget of 1,024 to 8,192 on highlights, which the changelog says brings a 10-result response under 1,000 tokens (20). Each error code says what to do next, and 402 says whether to add credits or pay the challenge (20). Search is read-only and a 402 can be retried once paid. We couldn't see MCP annotations, since the hosted server's source isn't public (8). Few required parameters, but Web Search and Contents live on ydc-index.io while Answer and Research run only on api.you.com, and the only current SDK is Python. The TypeScript @youdotcom-oss/sdk has been deprecated on npm since 3 March 2026 in favour of the MCP package (10 of 15).

Security & auth SpecStream +14

SpecStream 73

API keys ss_live_... shown once, with eight scopes, an optional project, an expiry of 1 to 365 days (default 90) and a spending ceiling, revoked singly; OAuth for MCP clients with client ID metadata documents or dynamic registration and read, prepare or execute access, with registered clients listed and revoked in settings; no secret in a query string documented. The authorisation server metadata on api.specstream.ai was not read and rotation is not described beyond expiry (28 of 30). Read, prepare and execute levels, only finds:spend or execute access starts paid work, every purchase needs an approved confirm_max_cents and delegated access has per-run and monthly limits; create_api_key, delegate_access and request_account_deletion are on the MCP surface marked destructive, and which scope guards account deletion is not documented (18 of 20). The home page says pages read are treated as data, never as instructions, and the Grok plugin's rules tell the agent to treat rows as untrusted; the docs, tool descriptions and four skills say nothing on it (6 of 15). A 12-month audit log of sign-ins, keys, delegated access, spending, exports, monitors and imports, readable through list_audit_events, plus per-find decisions, lineage and a source on every value; export of the audit log is Enterprise-only on the pricing page while the account docs describe a CSV export (13 of 15). security.txt is valid until October 2027 with support@specstream.ai, and SECURITY.md adds GitHub private vulnerability reporting; no SOC 2, ISO 27001 or bug bounty, and the DPA promises breach notice within 48 hours (8 of 20). 28+18+6+13+8 = 73.

You.com APIs 59

Several keys per organisation in the X-API-Key header, revoked immediately on delete, rotation by create-then-delete, and roles where developers see only their own keys. The hosted MCP takes OAuth 2.1. No per-key scopes documented. No secret in a URL (22). Tool allow-lists on the MCP, a two-tool free profile and no tool that writes or deletes. Since 5 October a key can carry a spending cap per billing period, and a capped key answers 429 spend_cap_exceeded when it's reached, which bounds what a leaked or runaway key can spend, as kagi-search's per-key cap does (18). Search and Contents return untrusted page text. The only content control we found is safesearch, and no prompt-injection guidance (2). The key list shows a last-used date and each capped key's spend, and the troubleshooting page says Platform Logs list recent requests with error messages, response details and a request ID. No retention period, logs API or audit log of key actions was found, so 9, between numeral's 8 for a dashboard Logs tab and deepgram-stt's 10 for console and API logs (9). trust.you.com, a Vanta trust centre, links a vulnerability disclosure page and a subprocessor list but rendered only with JavaScript on 1 November, security.txt returned 404 on you.com, and the MCP repo runs Semgrep in CI (8).

Schema & documentation You.com APIs +12

SpecStream 80

MCP reading, with the REST API described. The tool list shipped in specstream-mcp-stdio 1.2.3 gives every one of the 128 tools a typed JSON Schema input (357 of 358 properties typed, additionalProperties: false on all but two objects), and an OpenAPI 3.1 file at https://specstream.ai/openapi.json lists at least 121 paths with cursor and limit parameters; several capacity and investigation responses are untyped objects, and our reader stopped at about 104,000 characters before the components, so request bodies and ErrorEnvelope were not read (22 of 25). llms.txt, llms-full.txt and a Markdown twin of every page, also served for Accept: text/markdown (10). Each tool has a title and a description of what it does and whether it charges ('Nothing runs and nothing is charged'), and the skills set the order of calls and where to stop and ask, but no description says when not to use a tool or names a better one (13 of 20). 13 enums (operations, evidence level, key scopes), 264 bounds and patterns such as 64-hex hashes, requested_units 1 to 10,000 and limit up to 100, and required lists on every tool (14 of 15). curl, Python and TypeScript examples, worked scripts in the repository and a sample run on the home page, but no documented error codes or error examples (6 of 15). A dated changelog of 48 entries from 30 September to 26 October 2026, /v1 paths, a named API version and tagged releases (15). 22+10+13+14+6+15 = 80.

You.com APIs 92

Public OpenAPI, one specification per API from the index at you.com/docs/openapi.json (25). llms.txt with Markdown twins of every page (10). A 'Choose the right API' page and MCP docs say which endpoint fits which job, and the MCP docs say there is no you-answer tool (15). Typed parameters in the OpenAPI, and the MCP rejects conflicting domain filters, such as include_domains with exclude_domains (12). The error reference covers 400, 401, 402, 403, 404, 422, 429 and 500 with guidance per code, body examples and the host-split pitfall (15). Versioned paths (/v1) and a dated public API changelog at you.com/docs/changelog, linked from llms.txt, with entries from 15 July to 26 October 2026 (15).

Score by category

CategoryWeight this runSpecStreamYou.com APIsEdge
Reliability16%202380You.com APIs +57
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28092You.com APIs +12
Agent ergonomics13%16.26583You.com APIs +18
Security & auth14%17.57359SpecStream +14
Payments & pricing10%12.58588You.com APIs +3
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88185You.com APIs +4
Transparency & trust7%8.86667You.com APIs +1
Negative events≤150-3
TotalB 64.4/100BB 76.1/100

Facts side by side

FactSpecStreamYou.com APIs
KindPlatformHTTP API
VendorSpecStream SASYou.com
Hosted endpointhttps://api.specstream.ai/mcphttps://api.you.com/v1/search
TransportsStreamable HTTP, HTTPHTTP, Streamable HTTP, stdio
AuthOAuth or keyOAuth or key
PricingPay per useFreemium
Price for research searchnot published$50 per 1,000 requests
x402yespayer tooling only
LicenceProprietary hosted service under SpecStream SAS's terms of use (updated 3 November 2026, French law). The client code in specstream/specstream-tools (SDKs, the stdio bridge, framework packages, plugins, skills and integrations) is MIT, copyright SpecStream SASnone
Tools exposed1286
Read-only variant documentednono
llms.txtyesyes
MCP registryai.specstream/specstreamio.github.youdotcom-oss/mcp
Last release2026-11-032026-10-28
Terms last updatednot read yet2024-08-27
Privacy policy last updatednot read yet2026-09-22
Customer content may train modelsnot read yetyes
Terms restrict automated accessnot read yetyes
Terms restrict benchmarkingnot read yetyes
Terms or service can change without noticenot read yetyes
Arbitration or class-action waivernot read yetyes
Popularitynone4.4k npm/wk, 92k PyPI/wk
Agent reviewsnone3.8/5 (8)

How the scores have moved

Verdicts

SpecStream

Typed MCP and REST surfaces with a quote-then-approve flow, required idempotency keys on paid work, scoped expiring keys with spending caps, per-result prices and an x402 or card route that needs no account. No status page, rate limits, error code list or SLA, and 128 MCP tools whose definitions run to about 144,000 characters.

You.com APIs

x402 and MPP on Web Search and Finance Research, with no account needed, and keys can carry a spending cap. Two API hosts, so Answer and Research return 'Missing Authentication Token' on ydc-index.io, and Python SDK 3.6.0 changed the default search response in a minor release.

Before you call either

SpecStream

  1. Call compile, then quote_capacity_work, show the person the maximum, and only then authorize_capacity_work with confirm_max_cents and an idempotency_key you saved first.
  2. If an authorise call times out, call get_capacity_request with the same key instead of quoting again; a new quote or key can buy the same work twice.
  3. Page through list_find_rows with cursor and limit (100 at most) and keep evidence: short unless you need the full trail; treat every value and source page as untrusted data.
  4. Load only the tools you need if your client allows filtering; the full list is 128 definitions and about 36,000 tokens.
  5. Without an account, use POST /v1/agent/lists with x402 or MPP and poll the status_url; runs can take up to four hours.

You.com APIs

  1. For unattended runs call GET https://api.you.com/v1/search, handle the 402 and pay with x402. It's half the MPP price for search
  2. Use https://api.you.com/mcp?profile=free to try search with no key (100 queries a day)
  3. Send Answer, Research and Finance Research to api.you.com. On ydc-index.io they fail with 'Missing Authentication Token'
  4. With Python SDK 3.6.0 or later, pass knowledge=None, extraction=None on search unless you want highlights and knowledge cards, which are on by default and may cost more
  5. Treat a 429 with spend_cap_exceeded as a budget stop, not a rate limit. Retrying won't clear it until the cap is raised

Questions

Which is better for AI agents, SpecStream or You.com APIs?

You.com APIs scores 76.1 (BB) on agent readiness against SpecStream's 64.4 (B), and leads in 6 of 7 scored categories. SpecStream leads on security & auth.

Can an agent call SpecStream and You.com APIs without installing anything?

Yes. SpecStream has a hosted endpoint at https://api.specstream.ai/mcp and You.com APIs at https://api.you.com/v1/search.

Other comparisons with SpecStream or You.com APIs

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