Gray Swan website screenshot

Gray Swan

Gray Swan AI is an AI security company that helps enterprises deploy AI with confidence. Its Cygnal product is a real-time, drop-in secure proxy that fronts LLM providers (OpenAI, Anthropic, and Gemini request formats) with input/output filtering and threat monitoring for jailbreaks and prompt injection, governed by versioned enforcement Policies managed over a REST API. Gray Swan also operates Shade (an adversarial red-teaming platform), Arena (a global adversarial red-teaming network), and adversarial model evaluations that frontier AI labs run before shipping. The company is SOC 2 Type 2 and Cyber Essentials certified.

Gray Swan publishes 3 APIs on the APIs.io network: Activity API, Cygnal API, and Policies API. Tagged areas include Company, Artificial Intelligence, AI Security, LLM Security, and Guardrails.

Gray Swan’s developer surface includes documentation, API reference, quickstart, signup flow, engineering blog, authentication, and 22 more developer resources.

🌐 Visit website 📡 Source on GitHub
40.8/100 developing ▬ flat Agent 27/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0
1 APIs
CompanyArtificial IntelligenceAI SecurityLLM SecurityGuardrailsRed TeamingAI GovernancePrompt InjectionModel SafetyAPI Security

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Composite quality — 40.8/100 · developing
Contract Quality 12.1 / 23
Developer Ergonomics 9.8 / 18
Access Clarity 6.6 / 18
Operational Transparency 1.5 / 12
Contract Governance 0.5 / 11
Discoverability 6.8 / 9
Create-or-Update Ergonomics 0.0 / 10
Agent readiness — 27/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 0 / 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 7 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 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
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.
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 github.com/api-evangelist/gray-swan: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 3

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

Gray Swan Activity API

The Activity API from Gray Swan — 1 operation(s) for activity.

Gray Swan Cygnal API

The Cygnal API from Gray Swan — 7 operation(s) for cygnal.

Gray Swan Policies API

The Policies API from Gray Swan — 8 operation(s) for policies.

Open Collections 4

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

API Collection

OPEN COLLECTION

Gray Swan AI Activity API

OPEN COLLECTION

Gray Swan AI Activity Cygnal API

OPEN COLLECTION

Gray Swan AI Activity Policies API

OPEN COLLECTION

Rate Limits 1

Documented rate limits and quota policies.

Gray Swan Rate Limits

0 limits

RATE LIMITS

Security Posture 4

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

Gray Swan Authentication

1 scheme

SECURITY

Gray Swan Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Gray Swan Vulnerability Disclosure

security.txt · contact published

SECURITY

Gray Swan Trust Center

SOC 2 Type 2, Cyber Essentials

SECURITY

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 Quickstart
Quickstart
 SignUp
SignUp

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

X-MCPServerCandidate
X-MCPServerCandidate
 LLMsTxt
LLMsTxt
 AgentSkill
AgentSkill
 WellKnown
WellKnown

Design & Contract 5

Pagination, idempotency, versioning, errors, and events

ErrorCatalog
ErrorCatalog
 Conventions
Conventions
 DataModel
DataModel
 Lifecycle
Lifecycle
 Conformance
Conformance

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization

Access & Security 7

Authentication, authorization, and security posture

Authentication
Authentication
 Compliance
Compliance
 SecurityTxt
SecurityTxt
 Security
Security
 VulnerabilityDisclosure
VulnerabilityDisclosure
 DomainSecurity
DomainSecurity
 TrustCenter
TrustCenter

Scroll for all 7

Operate 1

Status, limits, changes, and where to get help

RateLimits
RateLimits

Commercial 2

Pricing, plans, and the legal terms of use

TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Company 2

The organization behind the API

Website
Website
 Blog
Blog

Other 1

Properties that don't map to a standard resource type

Overlay
Overlay

Source (apis.yml)

apis.yml Raw ↑ 
aid: gray-swan
name: Gray Swan
description: Gray Swan AI is an AI security company that helps enterprises deploy AI with confidence. Its Cygnal product is
  a real-time, drop-in secure proxy that fronts LLM providers (OpenAI, Anthropic, and Gemini request formats) with input/output
  filtering and threat monitoring for jailbreaks and prompt injection, governed by versioned enforcement Policies managed
  over a REST API. Gray Swan also operates Shade (an adversarial red-teaming platform), Arena (a global adversarial red-teaming
  network), and adversarial model evaluations that frontier AI labs run before shipping. The company is SOC 2 Type 2 and Cyber
  Essentials certified.
url: https://raw.githubusercontent.com/api-evangelist/gray-swan/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- wing-venture-capital
x-tier: enriched
x-tier-reason: portfolio-lead
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:
  - authentication
  - rate-limits
  - security
  generated: '2026-09-03'
  method: derived
image: https://cdn.prod.website-files.com/6614467b00e631b0f073e2b7/66886e33ca0b8f284d3b3b40_ca18847e7b3f6e2e7038dac7bd3846ce_Gray%20Swan%3DWhite%20Horizontal.svg
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Artificial Intelligence
- AI Security
- LLM Security
- Guardrails
- Red Teaming
- AI Governance
- Prompt Injection
- Model Safety
- API Security
tags_raw:
- Company
- Ai
- AI Security
- LLM Security
- Guardrails
- Red Teaming
- AI Governance
- Prompt Injection
- Model Safety
- API Security
apis:
- aid: gray-swan:gray-swan-activity-api
  name: Gray Swan Activity API
  description: The Activity API from Gray Swan — 1 operation(s) for activity.
  humanURL: https://docs.grayswan.ai/api-reference
  baseURL: https://api.grayswan.ai
  tags:
  - Activity
  properties:
  - type: OpenAPI
    url: openapi/gray-swan-activity-api-openapi.yml
  - type: Documentation
    url: https://docs.grayswan.ai/
  - type: APIReference
    url: https://docs.grayswan.ai/api-reference
- aid: gray-swan:gray-swan-cygnal-api
  name: Gray Swan Cygnal API
  description: The Cygnal API from Gray Swan — 7 operation(s) for cygnal.
  humanURL: https://docs.grayswan.ai/api-reference
  baseURL: https://api.grayswan.ai
  tags:
  - Cygnal
  properties:
  - type: OpenAPI
    url: openapi/gray-swan-cygnal-api-openapi.yml
  - type: Documentation
    url: https://docs.grayswan.ai/
  - type: APIReference
    url: https://docs.grayswan.ai/api-reference
- aid: gray-swan:gray-swan-policies-api
  name: Gray Swan Policies API
  description: The Policies API from Gray Swan — 8 operation(s) for policies.
  humanURL: https://docs.grayswan.ai/api-reference
  baseURL: https://api.grayswan.ai
  tags:
  - Policies
  properties:
  - type: OpenAPI
    url: openapi/gray-swan-policies-api-openapi.yml
  - type: Documentation
    url: https://docs.grayswan.ai/
  - type: APIReference
    url: https://docs.grayswan.ai/api-reference
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: X-MCPServerCandidate
  url: mcp/gray-swan-mcp.yml
  note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list derived
    from the published API contracts, not an existing server. The scorer already read the manifest and reported mcp_server
    correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- type: Overlay
  url: overlays/gray-swan-cygnal-overlay.yaml
- type: Website
  url: https://www.grayswan.ai/
- type: DeveloperPortal
  url: https://docs.grayswan.ai/
- type: Documentation
  url: https://docs.grayswan.ai/
- type: APIReference
  url: https://docs.grayswan.ai/api-reference
- type: Quickstart
  url: https://docs.grayswan.ai/cygnal/creating-completions
- type: SignUp
  url: https://platform.grayswan.ai
- type: Blog
  url: https://www.grayswan.ai/blog
- type: GitHubOrganization
  url: https://github.com/GraySwanAI
- type: TermsOfService
  url: https://www.grayswan.ai/terms-of-service
- type: PrivacyPolicy
  url: https://www.grayswan.ai/privacy-policy
- type: Authentication
  url: authentication/gray-swan-authentication.yml
- type: ErrorCatalog
  url: errors/gray-swan-problem-types.yml
- type: RateLimits
  url: rate-limits/gray-swan-rate-limits.yml
- type: Conventions
  url: conventions/gray-swan-conventions.yml
- type: DataModel
  url: data-model/gray-swan-data-model.yml
- type: Lifecycle
  url: lifecycle/gray-swan-lifecycle.yml
- type: Conformance
  url: conformance/gray-swan-conformance.yml
- type: Compliance
  url: conformance/gray-swan-conformance.yml
- type: LLMsTxt
  url: llms/gray-swan-llms.txt
- type: AgentSkill
  url: skills/_index.yml
- type: WellKnown
  url: well-known/gray-swan-well-known.yml
- type: SecurityTxt
  url: well-known/gray-swan-security.txt
- type: Security
  url: https://grayswan.ai/security
- type: VulnerabilityDisclosure
  url: security/gray-swan-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/gray-swan-domain-security.yml
- type: TrustCenter
  url: security/gray-swan-trust-center.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

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