Head to head · Web search · October 2026 research run

Grounding with Bing Search vs SpecStream

SpecStream and Grounding with Bing Search score within a point of each other on agent readiness, 64.4 (B) and 63.7 (B). Grounding with Bing Search leads on reliability and security & auth. Both do web search. SpecStream accepts x402. Grounding with Bing Search doesn't.

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

Which one, for what

Grounding with Bing Search B

Best for Teams already building on Foundry Agent Service who want cited answers from Bing without handling a search key.

Ahead on

  • Reliability, 68 against 23
  • Security & auth, 79 against 73

Watch for

The Bing tools never return raw results to developers, only a model-written answer with citation links

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

  • Schema & documentation, 80 against 68
  • Payments & pricing, 85 against 20

Also in its favour

  • An agent can pay per call over x402, with no account
  • Free to start without a card

Watch for

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

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 SpecStream +65

Grounding with Bing Search 20

No x402, MPP or L402 (0). $14 per 1,000 transactions for Grounding with Bing Search and Custom Search, published on microsoft.com without a login (20). No free tier for Grounding with Bing, and an Azure subscription needs a card, as on the Azure Translator listing (0). A person signs up for Azure, creates a Foundry project and, for bing_grounding, a Bing resource (0).

SpecStream 85

x402 v2 (USDC on Base, Arbitrum or Polygon, Permit2 upto for the quoted maximum, settled for the results cost) and MPP by card on SpecStream's own POST /v1/agent/lists, the route for buying a list of 1 to 500 results without an account; enrichment of imported lists, refreshes, monitors and investigations need an account, and the route was read in the docs and not exercised because api.specstream.ai's robots.txt could not be read, so partial (25). Per-result prices published without a login, 5, 15 or 100 cents a result, 5 cents an email, 15 cents a phone, rechecks at half rate or 1 cent (20). $10 of work for 30 days with no card (20). An agent can buy a list over x402 or MPP with no account, and the A2A endpoint prices a request without a key (20). 25+20+20+20 = 85.

Reliability Grounding with Bing Search +45

Grounding with Bing Search 68

Graded on the hosted lines, for the Foundry Agent Service tools agents call. Azure status page with post-incident reviews and a Foundry Agent Service component (20). The history page read on 6 November lists one review in the 90 days from 8 August that names Foundry Agent Service, intermittent failures and latency in Sweden Central from 10:03 to 15:58 UTC on 29 September 2026. It was one region and partial, and the review doesn't name Grounding with Bing, so minor only, the reading the Azure Translator listing got for the same review (20). The pricing page publishes 150 transactions a second and 1 million a day for each Grounding with Bing resource (15). The web search troubleshooting table says to answer 429 with exponential backoff and retries. No Retry-After or tool-specific overload guidance was found, and searches have no side effects (8 of 15). No SLA naming Grounding with Bing was found. The terms make it a First Party Consumption Service apart from the Online Services terms, and the Online Services SLA document wasn't opened (0). Grounding with Bing Custom Search is marked preview and Grounding with Bing Search is not, but no page read states general availability for it or for the web_search tool, and the .NET SDK is in preview (5 of 10). 20 + 20 + 15 + 8 + 0 + 5 = 68.

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.

Schema & documentation SpecStream +12

Grounding with Bing Search 68

The tools are typed in the official SDKs (BingGroundingTool, BingCustomSearchPreviewTool, WebSearchTool) in Python, C#, JavaScript and Java, and the toolbox exposes web search as an MCP tool. No public OpenAPI description of the Responses tool types was confirmed from the pages read (10 of 25). Microsoft Learn serves each page as Markdown with accept=text/markdown, though learn.microsoft.com/llms.txt answers 404 (10). The pages say what each of four web grounding routes is for and when to choose it, when to use Custom Search instead, and not to ask the model to summarise a whole page (17 of 20). Parameters are typed with defaults and limits in prose, count 1 to 50 with default 5, freshness values and a date-range form, market and language formats, search_context_size low, medium or high (11 of 15). Examples in Python, C#, TypeScript, Java and REST with expected output, and troubleshooting tables for connection ID, authentication and 429 problems, but no error codes or bodies for the tools (10 of 15). Requests carry api-version=v1 on the toolbox, SDK changelogs are dated and a monthly What's New page lists new articles, the latest for August 2026 (10 of 15). 10 + 10 + 17 + 11 + 10 + 10 = 68.

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.

Security & auth Grounding with Bing Search +6

Grounding with Bing Search 79

Callers authenticate to the Foundry project with Microsoft Entra ID tokens and RBAC roles (Foundry User to run agents, Foundry Project Manager to add connections), with just-in-time Contributor through Entra PIM for provisioning. The Bing resource key sits in a project connection and the agent never holds it. No key in a URL (28 of 30). The tools only read. Custom Search confines grounding to configured public domains, and an admin can turn web search off for a whole subscription. There is no per-agent read-only toggle to set, since the tools have no write path (15 of 20). The web search page tells developers to treat web search results as untrusted input and to keep secrets and personal data out of prompts, and the tool best practices page says the same of all tool outputs. Raw results are not passed back to the caller (10 of 15). Run steps show each tool call and the Bing query sent, and Azure's activity log covers resource changes. No per-query audit log for Bing was found (10 of 15). Microsoft runs a coordinated vulnerability disclosure policy and bounty programmes through MSRC. microsoft.com's security.txt passed its Expires date on 23 September 2026 and still carries it on 6 November, and the Azure compliance attestations are not shown to cover a service whose data leaves the compliance boundary (16 of 20). 28 + 15 + 10 + 10 + 16 = 79.

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.

Score by category

CategoryWeight this runGrounding with Bing SearchSpecStreamEdge
Reliability16%206823Grounding with Bing Search +45
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26880SpecStream +12
Agent ergonomics13%16.26165SpecStream +4
Security & auth14%17.57973Grounding with Bing Search +6
Payments & pricing10%12.52085SpecStream +65
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88081SpecStream +1
Transparency & trust7%8.86666even
Negative events≤1500
TotalB 63.7/100B 64.4/100

Facts side by side

FactGrounding with Bing SearchSpecStream
KindHTTP APIPlatform
VendorMicrosoftSpecStream SAS
Hosted endpointhttps://{account}.services.ai.azure.com/api/projects/{project}/openai/v1/responseshttps://api.specstream.ai/mcp
TransportsStreamable HTTPStreamable HTTP, HTTP
AuthOAuthOAuth or key
PricingPay per usePay per use
Price for web search$14 per 1,000 requestsnot published
x402noyes
LicenceProprietary service under the customer's Microsoft agreement and the separate Grounding with Bing terms of use, which exclude it from the Microsoft Data Protection AddendumProprietary 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 SAS
Tools exposed3128
Read-only variant documentednono
llms.txtnoyes
MCP registrynot listedai.specstream/specstream
Last release2026-11-022026-11-03
Terms last updated2025-11-01not read yet
Privacy policy last updated2026-09-01not read yet
Customer content may train modelsyesnot read yet
Terms restrict automated accessyesnot read yet
Terms restrict benchmarkingnot found in the textnot read yet
Terms or service can change without noticenot found in the textnot read yet
Arbitration or class-action waivernot found in the textnot read yet

Verdicts

Grounding with Bing Search

First-party Bing grounding inside Foundry Agent Service, called with Entra ID so the agent never holds a search key, at a published $14 per 1,000 transactions. The tools return a model's answer with citations, never the raw results, and data sent to them falls outside Microsoft's Data Protection Addendum and Azure's compliance boundary.

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.

Before you call either

Grounding with Bing Search

  1. Use the citations in the response annotations as the sources; the tool output itself is not returned, and the terms require showing the URLs and the Bing query link
  2. Expect each run to bill one transaction per tool call at $14 per 1,000, plus model tokens, and set count and freshness in the tool configuration
  3. Treat cited page text as untrusted input and don't put secrets or personal data in prompts, since queries leave the Azure compliance boundary
  4. On 429 back off exponentially; no Retry-After header is documented for the tool

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.

Questions

Which is better for AI agents, Grounding with Bing Search or SpecStream?

SpecStream and Grounding with Bing Search score within a point of each other on agent readiness, 64.4 (B) and 63.7 (B). Grounding with Bing Search leads on reliability and security & auth.

Can an agent call Grounding with Bing Search and SpecStream without installing anything?

Yes. Grounding with Bing Search has a hosted endpoint at https://{account}.services.ai.azure.com/api/projects/{project}/openai/v1/responses and SpecStream at https://api.specstream.ai/mcp.

Other comparisons with Grounding with Bing Search or SpecStream

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