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Head to head · Commerce orders · October 2026 research run

Fabric vs Square

Square scores 69.2 (B) on agent readiness against Fabric's 43.7 (E), and leads in every scored category. Both do commerce orders.

Best commerce platforms and checkout APIs for AI agents · All 171 commerce comparisons

FabricCommerce Fabric, Inc. · HTTP API E43.7/100#949 of 1076 SquareBlock, Inc. · HTTP API B69.2/100#202 of 1076

Which one, for what

Fabric E

Best for A merchant-side API for retailers already on Fabric's order management, catalogue or dropship products.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

No public price, free tier or self-serve signup. A trial account is arranged with Fabric

Square B

Best for Agents working for a seller already on Square, on catalogue, inventory, orders, payment links and customers, online and in person.

Ahead on

  • Reliability, 58 against 23
  • Schema & documentation, 87 against 79
  • Agent ergonomics, 83 against 57
  • Security & auth, 67 against 62
  • Payments & pricing, 40 against 0
  • Maintenance & community, 81 against 15
  • Transparency & trust, 70 against 55

Also in its favour

  • Runs on your own machine

Watch for

The MCP server is marked beta, and the remote server reaches production data only

Score by category

CategoryWeight this runFabricSquareEdge
Reliability16%202358Square +35
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27987Square +8
Agent ergonomics13%16.25783Square +26
Security & auth14%17.56267Square +5
Payments & pricing10%12.5040Square +40
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.81581Square +66
Transparency & trust7%8.85570Square +15
Negative events≤1500
TotalE 43.7/100B 69.2/100

Facts side by side

FactFabricSquare
KindHTTP APIHTTP API
VendorCommerce Fabric, Inc.Block, Inc.
Hosted endpointhttps://api.fabric.inc/v3https://mcp.squareup.com/mcp
TransportsHTTPHTTP, Streamable HTTP, stdio
AuthOAuthOAuth or key
PricingPaidPay per use
x402nono
LicenceProprietary SaaS under Fabric's Terms and Conditions (last updated 1 January 2026) and an order formProprietary service under the Square Developer Terms of Service. The MCP server and the OpenAPI specification on GitHub are Apache 2.0, and the Node.js SDK is MIT
Tools exposednone3
Read-only variant documentednono
llms.txtyesyes
Last releasenone2026-09-16
Terms last updated2026-01-012026-09-10
Privacy policy last updated2021-01-142026-09-15
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessnot found in the textyes
Terms restrict benchmarkingyesyes
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waivernot found in the textyes
Popularitynone454k npm/wk, 72k PyPI/wk

Verdicts

Fabric

Public OpenAPI files for about 980 operations, llms.txt, client credentials with role-limited system apps, and a published 99.9 per cent SLA. Access needs a sales contract, with no public price or self-serve trial. The commerce docs are labelled legacy, the newest release notes date from July 2025, and no status page was found.

Square

The REST API has a public OpenAPI 3.0 spec, OAuth scopes split by read and write for each resource, idempotency keys on writes and a free sandbox. The MCP server is in beta and its remote instance reaches production only. No numeric REST rate limits or SLA were found, and the status page recorded widespread errors on 27 September 2026.

Before you call either

Fabric

  1. Get the tenant ID and a System App client ID and secret from the merchant's Copilot admin, with the narrowest role the task needs
  2. Request a new system token from {authURL}/v1/token every 10 minutes, since system apps receive no refresh token
  3. Send x-fabric-tenant-id on every call, and x-fabric-channel-id where the merchant sells in more than one channel
  4. Page order searches with offset and limit, because the default response returns 10 orders
  5. Read errorCode and context.endpoint in Orders and Inventory errors, and check for duplicates before retrying a write

Square

  1. Test against the sandbox first with the local MCP server and SANDBOX=true. The remote server at mcp.squareup.com reaches production only
  2. Set DISALLOW_WRITES=true on the local MCP server when the task only reads
  3. Call get_service_info, then get_type_info, before each make_api_request. The request body is otherwise untyped
  4. Send a fresh idempotency_key on every write, and reuse it when retrying the same write
  5. Pin Square-Version in each request. Use a page cursor within 5 minutes of receiving it

Questions

Which is better for AI agents, Fabric or Square?

Square scores 69.2 (B) on agent readiness against Fabric's 43.7 (E), and leads in every scored category.

Do Fabric and Square need an API key?

Fabric uses an OAuth sign-in. Square takes an API key or an OAuth sign-in.

Can an agent call Fabric and Square without installing anything?

Yes. Fabric has a hosted endpoint at https://api.fabric.inc/v3 and Square at https://mcp.squareup.com/mcp.

Other comparisons with Fabric or Square

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