Squaresquare.com
Square's API Design and Developer Experience are strong foundations that partners can build on with confidence. md instruction file and no structured data on the docs, which means AI coding agents and automated tools cannot reliably interpret or act on Square's API surface without manual intervention.
API DesignA clean, typed, well-governed API contract agents can reason about3 pass2 warn0 fail91A+
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Auth declared & discoverablevia docs | 25/25 | authentication documented in the docs site at https://developer.squareup.com/docs/oauth-api/best-practices. Investigated: docs 100%, spec 50%. | Agents can only authenticate when auth is declared, scoped, and discoverable. |
| warn | Schema coverage & depthvia spec | 20.8/25 | Medium parameter complexity (avg 2.6 params/op; nested/body schemas present). Investigated: spec 83%. | Typed, complete request/response schemas are what make agent function-calling possible. |
| warn | Machine-readable, versioned contractvia spec | 18.8/25 | info.version="1.0.0" set but no versioning scheme (URL / header / media type) detected. Investigated: spec 75%, docs 50%. | A current OpenAPI version with a declared versioning scheme lets agents reason about the contract. |
| pass | Security & governance hygienevia spec | 15/15 | No credential-shaped strings detected in spec. Investigated: spec 100%, wellknown 0%. | No leaked secrets, no critical lint violations, no OWASP API Top-10 spec smells, and a published vulnerability-disclosure channel. |
| pass | Example coveragevia spec | 10/10 | 100% example coverage across params + responses. Investigated: spec 100%, docs 100%. | Examples carry shape semantics schemas under-specify — for humans and agents alike. |
Developer ExperienceThe context both developers and agents need to integrate fast — onboarding, code samples, complete descriptions and worked examples4 pass1 warn0 fail89A
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Self-service developer portalvia docs | 29/29 | Self-service signup at https://developer.squareup.com/docs/square-get-started; free tier / sandbox documented. Investigated: docs 100%. | Self-serve key/account creation is the fast first call for partners, with no sales gate. |
| pass | Code samples in docsvia docs | 18/18 | Code samples in 3 language(s) across docs (top: shell, go, curl); 1/3 pages have ≥ 2 languages on the same page. Investigated: docs 100%. | Multi-language samples shorten time-to-first-call. |
| pass | Description completenessvia spec | 15/15 | 63% description completeness (target 90%+). Investigated: spec 100%. | Complete descriptions are the context humans and agents need to use endpoints. |
| pass | Changelog publishedvia sdk | 13/13 | Newest official SDK activity 15 day(s) ago. Investigated: sdk 100%, spec 0%, docs 0%. | A published changelog lets partners track changes without surprise. |
| warn | Quickstart presentvia docs | 12.5/25 | Quickstart page reachable (2 variants scanned starting at https://developer.squareup.com/docs/square-get-started) but no runnable code sample detected in HTML or .md variant. Investigated: docs 50%. | A quickstart is the fastest path from landing page to first successful call. |
Agent DiscoveryPartners and their agents can find your APIs — llms.txt, registries, crawlable and reachable docs1 pass3 warn0 fail73B
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Registry & SDK presencevia docs | 28/28 | Indexed on Context7 (websites/developer_squareup, 11441 snippets). Investigated: docs 100%, sdk 100%, cli 0%. | Listing in MCP registries and publishing SDKs puts the API where agents and their tooling look. |
| warn | Docs reachable, not hard auth-gatedvia docs | 22.5/30 | Server ignores Accept: text/markdown header (0/50 sampled pages return markdown); 28 rate-limited (HTTP 429). Investigated: docs 75%. | Agents can only index and fetch docs they can reach — past auth gates and over correct HTTP semantics. |
| warn | llms.txt present, valid & comprehensivevia docs | 11.3/30 | No llms.txt directive found in HTML of any of 26 sampled pages; 24 failed to fetch. Investigated: docs 38%. | A valid, comprehensive llms.txt is the machine-readable entry point for agents. |
| warn | Crawlable / AEOvia wellknown | 6/12 | No sitemap discoverable via robots.txt or /sitemap.xml on the docs host. Investigated: wellknown 50%. | Bots allowed plus a fresh sitemap make docs findable by agent crawlers. |
Agent UnderstandingAgents can correctly interpret your APIs — machine-readable errors, consistent descriptions, structured data, parseable docs2 pass2 warn2 fail71B
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Machine-readable errors (RFC 9457)via spec | 28/28 | error codes documented in the docs site at https://developer.squareup.com/docs/payments-api/error-codes. Investigated: spec 100%, docs 100%. | RFC 9457 problem details and a documented error-code inventory let agents parse failures without burning tokens. |
| pass | Operation purpose clarityvia spec | 25/25 | 98% of operations have a clear summary + operationId an agent can select on. Investigated: spec 100%. | Agents select the right endpoint from its summary + operationId; clear, named operations make tool-selection reliable — the strongest driver of correct tool choice. |
| warn | Agent-navigable, token-efficient docsvia docs | 11/22 | 2 of 50 sampled pages appear to be client-side rendered SPA shells (__next detected); agents using HTTP fetches will see no content; 4 more have page structure but little substantive content. Investigated: docs 50%. | Server-rendered, clean, small-footprint docs are what an agent can cheaply fetch and parse correctly. |
| warn | Description consistency across surfaces | 0.4/7 | Mean pairwise description similarity across 2 surfaces (spec, docs) is 2% (threshold 35% for full credit). | Every surface tells the same story about what the product is. |
| fail | Agent instructions file (AGENTS.md)via wellknown | 0/10 | No AGENTS.md at the site root or /.well-known/. Investigated: wellknown 0%. | An AGENTS.md gives coding agents explicit setup, auth, and usage instructions to interpret and operate the API — beyond llms.txt's link index. |
| fail | Docs structured datavia docs | 0/8 | Neither JSON-LD nor OpenGraph/meta tags detected across 1 assessed pages (1 JS-rendered). Investigated: docs 0%. | Structured data (JSON-LD/schema.org) on docs pages gives agents an unambiguous parse target and is what answer engines cite. Detected on the JS-rendered head (Firecrawl) for a bounded page budget, so JS-injected JSON-LD is now caught; pages we can't render are excluded rather than failed. |
Agent UsabilityAgents have the context to use your APIs reliably, not just find them3 pass2 warn0 fail87A
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Idempotency documentedvia spec | 27/27 | idempotency documented in the docs site at https://developer.squareup.com/docs/build-basics/common-api-patterns/idempotency. Investigated: spec 100%, docs 100%. | Documented idempotency lets agents retry safely. |
| pass | Pagination documented & consistentvia docs | 22/22 | pagination documented in the docs site at https://developer.squareup.com/docs/build-basics/common-api-patterns/pagination. Investigated: docs 100%, spec 50%. | Consistent, documented pagination lets agents traverse collections. |
| pass | Sandbox separationvia spec | 20/20 | sandbox documented in the docs site at https://developer.squareup.com/docs/devtools/sandbox/overview. Investigated: spec 100%, docs 100%. | An isolated environment lets agents exercise destructive operations safely. |
| warn | Rate-limit signalingvia spec | 11/22 | No rate-limit response headers documented. Investigated: spec 50%, docs 50%. | Machine-readable rate-limit headers let agents throttle adaptively. |
| warn | Runnable collection with test scriptsvia platform | 4.5/9 | No test scripts found in the workspace's collections. Investigated: platform 50%. | A public, maintained collection with assertions is runnable truth agents validate against. |
Resources Discovered
The public resources we found for Square — the evidence behind the score. All discovered from public sources; nothing here requires access to your systems.
| Agent hints | Context7 (11,441) |
|---|---|
| APIs analyzed | 2 — LeadSquared Sales CRM, LeadSquared Service CRM |