SmallStep

Smallstep operates the world's first Device Identity Platform. It issues hardware-backed, short-lived X.509 and SSH certificates that cryptographically prove what is acting and from where — for devices, humans, workloads, AI agents, and MCP toolchains. Smallstep co-developed ACME Device Attestation (ACME DA) with Google through the IETF, using TPM and Secure Enclave co-processors to bind non-exportable credentials to specific devices at issuance. Its OpenAPI-conformant Platform API (gateway.smallstep.com) manages device inventory, PKI (certificate authorities and provisioners), certificate issuance and revocation, credentials, and protected resources such as Wi-Fi, VPN, and SSO. Smallstep also maintains the widely used open-source step CLI and step-ca certificate authority.

SmallStep publishes 6 API contracts indexed on the APIs.io network, including Authentication API, Certificates API, Credentials API, and 3 more. Tagged areas include Company, Developer Tools, Certificate Authority, PKI, and Device Identity.

The SmallStep catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

SmallStep’s developer surface includes documentation, API reference, getting-started guide, engineering blog, support, pricing, authentication, and 30 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

59.5/100 strong ▬ flat Agent 30/100 agent ready Front door AI 5/6 prominent Heartbeat 59/100 alive saas Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

1 published contract 3 Agent Skills

Company Developer Tools Certificate Authority PKI Device Identity Zero Trust Certificate Management mTLS ACME SSH Security

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Cybersecurity Management

BC-620

CertificatesCredentialsPKI ArchitectureProtect

GET /certificates POST /certificates/{serialNumber}/revoke DELETE /credential/{credentialID} POST /credentials

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 59.5/100 · strong

Contract Quality 11.9 / 19

Developer Ergonomics 11.2 / 15

Access Clarity 8.9 / 15

Operational Transparency 4.4 / 10

Contract Governance 1.6 / 9

Discoverability 5.5 / 8

Regulatory Posture 4.6 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 30/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Rate-Limit Signaling +7 pts — OpenAPI responses document X-RateLimit-* / RateLimit headers (verified), else a rate_limits artifact or RateLimits link (documented)
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document

7 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Governance scores 18.2 — up to +9.8 composite points
Contract Quality scores 63.7 — up to +9.1 composite points
Access Clarity scores 59.2 — up to +8.2 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/smallstep/apis.yml: open an issue on github.com/api-evangelist/smallstep to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
PKI and Encryption (certificate authorities, key management)	builds-on	43.1	-	-
Configuration-Management Content Registries (Ansible Galaxy, Chef Supermarket)	builds-on	43.1	-	-
Buf Schema Registry (public Protocol Buffers modules, gRPC / ConnectRPC schema publishers)	builds-on	43.1	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

Standards implemented 3

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

Mutual TLS

measured — observed by APIs.io (declared)

SSH

tagged — the provider's own APIs.json carries the standard as a tag; implementation not verified

OpenAPI

measured — observed by APIs.io (published)

APIs 6

Individual APIs this provider publishes, each with its own machine-readable definition.

SmallStep Authentication API

Create API tokens

SmallStep Certificates API

Query certificates and their statuses issued by authorities

SmallStep Credentials API

Manage credentials

SmallStep Device Inventory API

Manage your device inventory

SmallStep PKI Architecture API

Manage certificate authorities and provisioners

SmallStep Protect API

Manage access to protected resources

Open Collections 6

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Smallstep Authentication API

OPEN COLLECTION

Smallstep Authentication Certificates API

OPEN COLLECTION

Smallstep Authentication Credentials API

OPEN COLLECTION

Smallstep Authentication Device Inventory API

OPEN COLLECTION

Smallstep Authentication PKI Architecture API

OPEN COLLECTION

Smallstep Authentication Protect API

OPEN COLLECTION

Agent Skills 3

Packaged agent skills for driving this provider's APIs from an AI assistant.

Search, inspect, and revoke Smallstep certificates

AGENT SKILL

Manage the Smallstep device inventory

AGENT SKILL

Provision a Smallstep certificate authority and provisioner

AGENT SKILL

SmallStep API pricing

Prices published by SmallStep, read 2026-10-28 from smallstep.com/pricing/.

Plan	Price
Platform / bespoke solutions	Contact us Includes: ACME Device Attestation, SSH, Certificate based Wi-Fi, VPN & ZTNA, Workload identity, Certificate Au

Plan details, limits and sources →

Pricing Plans 1

Published pricing tiers and plan structures.

Smallstep Plans Pricing

1 plans

PLANS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

SmallStep

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Smallstep Finops

FINOPS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Smallstep Webhooks

ASYNCAPI

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

SmallStep API Rules

68 rules · 59 errors 8 warnings 1 info

SPECTRAL

OpenAPI Overlays 1

Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.

Smallstep Platform Overlay

2 actions · update · smallstep-openapi-original.yml

DERIVED

Security Posture 3

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Smallstep Authentication

http/mutualTLS · 2 schemes

SECURITY

Smallstep Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Smallstep Vulnerability Disclosure

security.txt · contact published

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Smallstep Agentic Access

74 operations · 44 acting · 1 human-in-the-loop

74 operations · 44 acting

AGENTIC

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

Login

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

WellKnown

LLMsTxt

AgentSkill

MCPServerCandidate

MCPServerCandidate

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Conformance

ErrorCatalog

Lifecycle

Conventions

DataModel

Webhooks

Build 5

SDKs, sample code, and the tooling you integrate with

PostmanWorkspace

PostmanWorkspace

GitHubOrganization

Packages

SDKs

CLI

Access & Security 5

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

VulnerabilityDisclosure

VulnerabilityDisclosure

Security

Security

SecurityTxt

SecurityTxt

Operate 3

Status, limits, changes, and where to get help

Support

Support

StatusPage

StatusPage

ChangeLog

ChangeLog

Commercial 4

Pricing, plans, and the legal terms of use

Plans

Pricing

TermsOfService

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Overlay

Overlay

Source (apis.yml)

x-enrichment:
  date: '2026-07-21'
  status: enriched
  artifacts_added: 23
  pass: local-v1
aid: smallstep
name: SmallStep
description: Smallstep operates the world's first Device Identity Platform. It issues hardware-backed, short-lived X.509 and
  SSH certificates that cryptographically prove what is acting and from where — for devices, humans, workloads, AI agents,
  and MCP toolchains. Smallstep co-developed ACME Device Attestation (ACME DA) with Google through the IETF, using TPM and
  Secure Enclave co-processors to bind non-exportable credentials to specific devices at issuance. Its OpenAPI-conformant
  Platform API (gateway.smallstep.com) manages device inventory, PKI (certificate authorities and provisioners), certificate
  issuance and revocation, credentials, and protected resources such as Wi-Fi, VPN, and SSO. Smallstep also maintains the
  widely used open-source step CLI and step-ca certificate authority.
url: https://raw.githubusercontent.com/api-evangelist/smallstep/refs/heads/main/apis.yml
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - plans
  - authentication
  - security
  generated: '2026-11-06'
  method: derived
image: https://smallstep.imgix.net/logo_bfa4201fe5.svg
x-type: company
x-source: vc-portfolio
x-backed-by:
- accel
- bain-capital-ventures
x-tier: enriched
x-tier-reason: portfolio-lead-enriched
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-21'
tags:
- Company
- Developer Tools
- Certificate Authority
- PKI
- Device Identity
- Zero Trust
- Certificate Management
- mTLS
- ACME
- SSH
- Security
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- aid: smallstep:smallstep-authentication-api
  name: SmallStep Authentication API
  description: Create API tokens
  humanURL: https://smallstep.com/docs/platform/smallstep-api/
  baseURL: https://gateway.smallstep.com/api
  tags:
  - Authentication
  properties:
  - type: OpenAPI
    url: openapi/smallstep-authentication-api-openapi.yml
  - type: Documentation
    url: https://smallstep.com/docs/platform/smallstep-api/
  - type: APIReference
    url: https://gateway.smallstep.com/v2025-01-01
- aid: smallstep:smallstep-certificates-api
  name: SmallStep Certificates API
  description: Query certificates and their statuses issued by authorities
  humanURL: https://smallstep.com/docs/platform/smallstep-api/
  baseURL: https://gateway.smallstep.com/api
  tags:
  - Certificates
  properties:
  - type: OpenAPI
    url: openapi/smallstep-certificates-api-openapi.yml
  - type: Documentation
    url: https://smallstep.com/docs/platform/smallstep-api/
  - type: APIReference
    url: https://gateway.smallstep.com/v2025-01-01
- aid: smallstep:smallstep-credentials-api
  name: SmallStep Credentials API
  description: Manage credentials
  humanURL: https://smallstep.com/docs/platform/smallstep-api/
  baseURL: https://gateway.smallstep.com/api
  tags:
  - Credentials
  properties:
  - type: OpenAPI
    url: openapi/smallstep-credentials-api-openapi.yml
  - type: Documentation
    url: https://smallstep.com/docs/platform/smallstep-api/
  - type: APIReference
    url: https://gateway.smallstep.com/v2025-01-01
- aid: smallstep:smallstep-device-inventory-api
  name: SmallStep Device Inventory API
  description: Manage your device inventory
  humanURL: https://smallstep.com/docs/platform/smallstep-api/
  baseURL: https://gateway.smallstep.com/api
  tags:
  - Device Inventory
  properties:
  - type: OpenAPI
    url: openapi/smallstep-device-inventory-api-openapi.yml
  - type: Documentation
    url: https://smallstep.com/docs/platform/smallstep-api/
  - type: APIReference
    url: https://gateway.smallstep.com/v2025-01-01
- aid: smallstep:smallstep-pki-architecture-api
  name: SmallStep PKI Architecture API
  description: Manage certificate authorities and provisioners
  humanURL: https://smallstep.com/docs/platform/smallstep-api/
  baseURL: https://gateway.smallstep.com/api
  tags:
  - PKI Architecture
  properties:
  - type: OpenAPI
    url: openapi/smallstep-pki-architecture-api-openapi.yml
  - type: Documentation
    url: https://smallstep.com/docs/platform/smallstep-api/
  - type: APIReference
    url: https://gateway.smallstep.com/v2025-01-01
- aid: smallstep:smallstep-protect-api
  name: SmallStep Protect API
  description: Manage access to protected resources
  humanURL: https://smallstep.com/docs/platform/smallstep-api/
  baseURL: https://gateway.smallstep.com/api
  tags:
  - protect
  tags_raw:
  - Protect
  properties:
  - type: OpenAPI
    url: openapi/smallstep-protect-api-openapi.yml
  - type: Documentation
    url: https://smallstep.com/docs/platform/smallstep-api/
  - type: APIReference
    url: https://gateway.smallstep.com/v2025-01-01
common:
- type: Plans
  url: plans/smallstep-plans-pricing.yml
- type: PostmanWorkspace
  url: https://www.postman.com/kinlaneapi/smallstep/overview
- type: CapabilityMap
  url: capabilities/smallstep-capability-edges.yml
  name: SmallStep Business Capability Map
- type: Overlay
  url: overlays/smallstep-platform-overlay.yaml
- type: Website
  url: http://www.smallstep.com
- type: DeveloperPortal
  url: https://smallstep.com/docs/
- type: Documentation
  url: https://smallstep.com/docs/platform
- type: APIReference
  url: https://smallstep.com/docs/platform/smallstep-api/
- type: GettingStarted
  url: https://smallstep.com/docs/certificate-manager/getting-started/
- type: Blog
  url: https://smallstep.com/blog
- type: GitHubOrganization
  url: https://github.com/smallstep
- type: Support
  url: https://github.com/smallstep/certificates/discussions
- type: Pricing
  url: https://smallstep.com/pricing
- type: Login
  url: https://smallstep.com/app/
- type: TermsOfService
  url: https://smallstep.com/terms-of-use
- type: PrivacyPolicy
  url: https://smallstep.com/privacy-policy
- type: StatusPage
  url: https://status.smallstep.com
- type: Authentication
  url: authentication/smallstep-authentication.yml
- type: AgenticAccess
  url: agentic-access/smallstep-agentic-access.yml
- type: DomainSecurity
  url: security/smallstep-domain-security.yml
- type: VulnerabilityDisclosure
  url: security/smallstep-vulnerability-disclosure.yml
- type: Security
  url: https://smallstep.com/security/
- type: SecurityTxt
  url: well-known/smallstep-security.txt
- type: WellKnown
  url: well-known/smallstep-well-known.yml
- type: Packages
  url: packages/smallstep-packages.yml
- type: SDKs
  url: packages/smallstep-packages.yml
- type: CLI
  url: cli/smallstep-cli.yml
- type: LLMsTxt
  url: llms/smallstep-llms.txt
- type: Conformance
  url: conformance/smallstep-conformance.yml
- type: ErrorCatalog
  url: errors/smallstep-problem-types.yml
- type: Lifecycle
  url: lifecycle/smallstep-lifecycle.yml
- type: Conventions
  url: conventions/smallstep-conventions.yml
- type: ChangeLog
  url: changelog/smallstep-changelog.yml
- type: DataModel
  url: data-model/smallstep-data-model.yml
- type: Webhooks
  url: asyncapi/smallstep-webhooks.yml
- type: AgentSkill
  url: skills/_index.yml
- type: MCPServerCandidate
  url: mcp/smallstep-mcp.yml

SmallStep API — frequently asked questions

Does SmallStep have an API?

Yes. APIs.io lists 6 APIs from SmallStep, including SmallStep Authentication API, SmallStep Certificates API and SmallStep Credentials API, and 3 more.

Is there an OpenAPI specification for the SmallStep API?

Yes. APIs.io indexes 6 OpenAPI specifications for SmallStep, each linked for download from this page.

How do I authenticate with the SmallStep API?

SmallStep documents its authentication (http/mutualTLS · 2 schemes). The details are profiled on APIs.io as Smallstep Authentication.

How much does the SmallStep API cost?

APIs.io lists 1 pricing plan for SmallStep, with each plan's price, limits and inclusions under Pricing on this page.

Is the SmallStep API ready for AI agents?

SmallStep has a Kin Score of 59.5 out of 100 (strong) and an Agent Readiness score of 30.1 (agent-ready), scored by API Evangelist on 2026-11-06.

Work with this as data

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