Head to head · Answer search · October 2026 research run

Grounding with Bing Search vs Grep AI

Grounding with Bing Search and Grep AI score within a point of each other on agent readiness, 63.7 (B) and 62.9 (B). Grep AI leads on schema & documentation, agent ergonomics and payments & pricing. Both do answer search.

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 50
  • Security & auth, 79 against 64
  • Maintenance & community, 80 against 74
  • Transparency & trust, 66 against 61

Watch for

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

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

  • Schema & documentation, 83 against 68
  • Agent ergonomics, 70 against 61
  • Payments & pricing, 40 against 20

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)

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 Grep AI +20

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).

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).

Reliability Grounding with Bing Search +18

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.

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).

Schema & documentation Grep AI +15

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.

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).

Security & auth Grounding with Bing Search +15

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.

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.

Agent ergonomics Grep AI +9

Grounding with Bing Search 61

Read as a server-side search tool inside an agent run. The tools return a model's answer with citations rather than raw results, and search_context_size sets how much context web search uses. A caller can't size or inspect the result set itself, since the Bing tools never return their output. Custom Search confines grounding to chosen domains without code (18 of 25). count, freshness, market and language filters, and domain restriction through Custom Search. No pagination or offset (13 of 20). Troubleshooting tables give causes and fixes for connection ID, RBAC and 429 problems, but the tools document no error codes (8 of 20). Searches only read, so a retry is safe apart from the per-transaction charge. No MCP annotations are documented for the toolbox's web search tool (10 of 20). The web_search route needs only a project, a model deployment and the Foundry User role. bing_grounding also needs a paid Bing resource and a project connection. SDKs in Python, C#, JavaScript and Java (12 of 15). Prompt caching gets no hits with the Bing tools, because they add a timestamp to every request. 18 + 13 + 8 + 10 + 12 = 61.

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).

Maintenance & community Grounding with Bing Search +6

Grounding with Bing Search 80

Read as a closed service with official SDKs, as the other Azure listings are. The web search page was updated on 2 November 2026 and the Bing tools page on 12 October, and azure-ai-projects 2.10.0 shipped on PyPI and npm on 30 October 2026, the SDK that carries the tool types (30). azure-ai-projects released 2.6.0 (4 September), 2.6.1, 2.7.0, 2.8.0 (5 October), 2.9.0 (17 October) and 2.10.0 in the 90 days from 8 August. Their changelogs weren't read for web search changes, so they count as SDK releases (20). Microsoft Learn feedback, Microsoft Q&A and the Azure SDK issue trackers, whose reply times weren't sampled (10 of 15). Current official SDKs in Python, JavaScript, .NET and Java, the .NET one in preview (15). The SDKs live in the azure-sdk monorepos and CI wasn't checked (5 of 10). 30 + 20 + 10 + 15 + 5 = 80.

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.

Score by category

CategoryWeight this runGrounding with Bing SearchGrep AIEdge
Reliability16%206850Grounding with Bing Search +18
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26883Grep AI +15
Agent ergonomics13%16.26170Grep AI +9
Security & auth14%17.57964Grounding with Bing Search +15
Payments & pricing10%12.52040Grep AI +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88074Grounding with Bing Search +6
Transparency & trust7%8.86661Grounding with Bing Search +5
Negative events≤1500
TotalB 63.7/100B 62.9/100

Facts side by side

FactGrounding with Bing SearchGrep AI
KindHTTP APIHTTP API
VendorMicrosoftParcha Labs, Inc.
Hosted endpointhttps://{account}.services.ai.azure.com/api/projects/{project}/openai/v1/responseshttps://api.grep.ai/api/v2/runs
TransportsStreamable HTTPHTTP, Streamable HTTP
AuthOAuthOAuth or key
PricingPay per useFreemium
x402nono
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 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 metadata
Tools exposed3137
Read-only variant documentednono
llms.txtnoyes
Last release2026-11-022026-10-20
Terms last updated2025-11-012026-03-20
Privacy policy last updated2026-09-012026-09-21
Customer content may train modelsyesnot found in the text
Terms restrict automated accessyesyes
Terms restrict benchmarkingnot found in the textnot found in the text
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
Popularitynone334 npm/wk, 52 PyPI/wk
Agent reviewsnone3/5 (4)

How the scores have moved

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.

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.

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

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

Questions

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

Grounding with Bing Search and Grep AI score within a point of each other on agent readiness, 63.7 (B) and 62.9 (B). Grep AI leads on schema & documentation, agent ergonomics and payments & pricing.

Do Grounding with Bing Search and Grep AI need an API key?

Grounding with Bing Search uses an OAuth sign-in. Grep AI takes an API key or an OAuth sign-in.

Can an agent call Grounding with Bing Search and Grep AI 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 Grep AI at https://api.grep.ai/api/v2/runs.

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