Citiciti.com
Citi's API program shows strong fundamentals in API design — the contract is well-structured, typed, and secure. md, no structured docs metadata), and onboarding speed (no quickstart or code samples).
API DesignA clean, typed, well-governed API contract agents can reason about2 pass3 warn0 fail81A
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| 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. |
| warn | Auth declared & discoverablevia docs | 17.2/25 | No securitySchemes declared. Investigated: docs 69%, spec 49%, wellknown 0%. | Agents can only authenticate when auth is declared, scoped, and discoverable. |
| warn | Schema coverage & depthvia spec | 16.1/25 | Only 0% of operations have documented schemas. Investigated: spec 65%. | Typed, complete request/response schemas are what make agent function-calling possible. |
| 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 0%. | 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 examples2 pass0 warn3 fail58D
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Self-service developer portalvia docs | 29/29 | Signup page at https://online.citi.com/US/ag/bank/registration/set-up-online-access; no free-tier language detected in docs/pricing. Investigated: docs 100%. | Self-serve key/account creation is the fast first call for partners, with no sales gate. |
| pass | Description completenessvia spec | 15/15 | 50% description completeness. Investigated: spec 100%. | Complete descriptions are the context humans and agents need to use endpoints. |
| fail | Quickstart presentvia docs | 0/25 | No quickstart/getting-started page found at the conventional paths. Investigated: docs 0%. | A quickstart is the fastest path from landing page to first successful call. |
| fail | Code samples in docsvia docs | 0/18 | No detectable code samples across 1 sampled docs pages. Investigated: docs 0%. | Multi-language samples shorten time-to-first-call. |
| fail | Changelog publishedvia spec | 0/13 | No changelog URL or mention found in spec metadata. Investigated: spec 0%, docs 0%. | A published changelog lets partners track changes without surprise. |
Agent DiscoveryPartners and their agents can find your APIs — llms.txt, registries, crawlable and reachable docs1 pass2 warn1 fail65C
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Registry & SDK presencevia docs | 28/28 | Indexed on Context7 (thecodecrate/city-state, 17 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 (0/1 pages return markdown). Investigated: docs 75%. | Agents can only index and fetch docs they can reach — past auth gates and over correct HTTP semantics. |
| 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. |
| fail | llms.txt present, valid & comprehensivevia docs | 0/30 | No llms.txt found at any candidate location (https://developer.citi.com/llms.txt, https://developer.citi.com/docs/llms.txt). Investigated: docs 0%. | A valid, comprehensive llms.txt is the machine-readable entry point for agents. |
Agent UnderstandingAgents can correctly interpret your APIs — machine-readable errors, consistent descriptions, structured data, parseable docs1 pass3 warn2 fail68C
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| pass | Machine-readable errors (RFC 9457)via docs | 28/28 | 6 distinct 4xx/5xx response codes documented. Investigated: docs 100%, spec 50%. | RFC 9457 problem details and a documented error-code inventory let agents parse failures without burning tokens. |
| warn | Agent-navigable, token-efficient docsvia docs | 15.7/22 | No pages support .md URLs (0/1 tested). Investigated: docs 71%. | Server-rendered, clean, small-footprint docs are what an agent can cheaply fetch and parse correctly. |
| warn | Operation purpose clarityvia spec | 15.6/25 | 0% of operations are agent-inferable. Investigated: spec 63%. | Agents select the right endpoint from its summary + operationId; clear, named operations make tool-selection reliable — the strongest driver of correct tool choice. |
| 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 them0 pass1 warn2 fail41F
| Signal | Points | Findings | Rationale | |
|---|---|---|---|---|
| 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. |
| fail | Idempotency documentedvia spec | 0/27 | 0% of mutating operations document idempotency. Investigated: spec 0%, docs 0%. | Documented idempotency lets agents retry safely. |
| fail | Rate-limit signalingvia spec | 0/22 | No rate-limit response headers documented. Investigated: spec 0%, docs 0%. | Machine-readable rate-limit headers let agents throttle adaptively. |
| na | Pagination documented & consistent | —/22 | No surface produced evidence for this capability in this run. | Consistent, documented pagination lets agents traverse collections. |
| na | Sandbox separation | —/20 | No surface produced evidence for this capability in this run. | An isolated environment lets agents exercise destructive operations safely. |
Resources Discovered
The public resources we found for Citi — the evidence behind the score. All discovered from public sources; nothing here requires access to your systems.
| Agent hints | Context7 (17) |
|---|---|
| APIs analyzed | 8 — Citi Accounts API, Citi Virtual Cards APIs, Authentication, Citi Statements API, Citi Payment Initiation API - pacs.008, Citi Payment Initiation API - pacs.009, Citi Payment Initiation API - pain.001, Citi Payment Initiation API - pain.008 |