Zally
Zally is an open source API linter from Zalando that validates OpenAPI 2 and 3 specifications against configurable rule sets for API design consistency. It exposes a REST API, command-line interface, and web UI for checking API designs against Zalando's RESTful API Guidelines or custom rule sets.
Solid contracts, transparent operations, and an easy start — typically complete on four or five facets with one clear soft spot.
API Evangelist profiles Zally the way a machine reads it — 49 machine-readable artifacts across 3 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Zally scores 60.0/100 (strong), with a separate agent-readiness read of 48/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile Zally
Each block below is one kind of artifact we hold for Zally. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 3
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
Zally Api Violations API
The Api Violations API from Zally — 2 operation(s) for api violations.
Zally Review Statistics API
The Review Statistics API from Zally — 1 operation(s) for review statistics.
Zally Supported Rules API
The Supported Rules API from Zally — 1 operation(s) for supported rules.
Open Collections 1
Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
Zally - Zalando's API Linter
OPEN COLLECTIONPricing Plans 1
Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.
Published pricing tiers and plan structures.
Zally Plans Pricing
PLANSRate Limits 1
Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.
Documented rate limits and quota policies.
Zally Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.
Cost, billing, and metering signals for API financial operations.
Zally Finops
FINOPSFeatures 6
The notable capabilities this provider advertises, captured as structured features so they can be searched and compared instead of read one landing page at a time.
Notable capabilities this provider offers.
API Linting
Validate OpenAPI 2/3 specifications against rule sets to enforce design consistency.
Configurable Rules
Customize default Zalando RESTful API Guidelines rules or define custom rule sets.
Multiple Interfaces
REST API for programmatic access, CLI for local checking, and Web UI for visual review.
Ignore Extension
Use x-zally-ignore extension in specs to selectively bypass rules.
Rule Severity Levels
Rules categorized as MUST, SHOULD, COULD, MAY, and HINT for graduated enforcement.
Linting Statistics
Track linting requests and aggregate review statistics over time.
Semantic Vocabularies 1
JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.
JSON-LD contexts and semantic vocabularies used across these APIs.
Zally Context
JSON-LDSpectral Rules 2
Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.
Zally API Rules
SPECTRALZally API Rules
SPECTRALJSON Schema 8
Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.
Standalone JSON Schema definitions for this provider's data models.
LintingRequest
JSON SCHEMALintingResponse
JSON SCHEMAReviewStatisticsResponse
JSON SCHEMARule
JSON SCHEMARuleType
JSON SCHEMASupportedRulesResponse
JSON SCHEMAViolation
JSON SCHEMAViolationsCount
JSON SCHEMAScroll within the panel for all 8 ·
JSON Structure 8
JSON Structure captures the data shapes in a form built for tooling — a complement to JSON Schema that keeps the model machine-legible.
JSON Structure definitions describing this provider's data shapes.
Zally Api Linting Request Structure
JSON STRUCTUREZally Api Linting Response Structure
JSON STRUCTUREZally Api Review Statistics Response Structure
JSON STRUCTUREZally Api Rule Structure
JSON STRUCTUREZally Api Rule Type Structure
JSON STRUCTUREZally Api Supported Rules Response Structure
JSON STRUCTUREZally Api Violation Structure
JSON STRUCTUREZally Api Violations Count Structure
JSON STRUCTUREScroll within the panel for all 8 ·
Examples 7
Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.
Example request and response payloads for these APIs.
Zally Api Rule Example
EXAMPLEZally Api Violation Example
EXAMPLEScroll within the panel for all 7 ·
Security Posture 2
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.
Recommended x-agentic-access execution contracts for AI agents.
Use Cases 4
What developers actually build with this provider — captured so the catalogue answers 'what is this for', not just 'what does this expose'.
What developers build with this provider.
API Design Review
Review OpenAPI specs in pull requests to enforce design standards before merge.
API Governance
Enforce organizational API guidelines across teams via shared rule sets.
API Quality Gate
Block API releases that violate critical MUST rules in CI/CD pipelines.
Style Guide Enforcement
Encode an API style guide as executable rules and apply consistently.
Integrations 3
Pre-built integrations with other platforms tell you where this provider already fits in a stack.
Pre-built integrations with other platforms and tools.
GitHub Actions
Run Zally linting in GitHub Actions workflows on PRs.
Spectral
Translate Zally rule sets to Spectral rulesets for OpenAPI 3 alignment.
Zalando RESTful API Guidelines
Default rule set ships with rules from Zalando's public API guidelines.
Resources
Every other property we hold for Zally — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Documentation 2
Reference material describing how the API behaves
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 2
Pagination, idempotency, versioning, errors, and events
Build 4
SDKs, sample code, and the tooling you integrate with
Access & Security 2
Authentication, authorization, and security posture
Operate 2
Status, limits, changes, and where to get help
Commercial 1
Pricing, plans, and the legal terms of use
Company 1
The organization behind the API
← All providers · Data indexed from github.com/api-evangelist/zally · machine-readable index on apis.io