c/side website screenshot

c/side

c/side (cside) is a client-side security platform that detects script attacks, AI agents, account takeover, and fraud at the browser layer. It provides active runtime detection that watches what third-party scripts, users, and agents actually do as they execute in the live browser session, in real time, rather than relying on static scans or block-lists, and it automates PCI DSS 4.0.1 requirements 6.4.3 and 11.6.1 (validated by a VikingCloud QSA). cside deploys as a single JavaScript snippet with no proxy and no DNS changes, and was the first client-side security product with integrated AI analysis. The platform protects websites from malicious third-party scripts, e-skimming, Magecart, and supply chain attacks, and adds device fingerprinting (102+ signals), VPN/bot/AI-agent detection, chargeback evidence, and privacy monitoring for GDPR, CCPA, and HIPAA. Founded in 2024 and backed by Uncork Capital, cside integrates via a CLI, Next.js and Vite plugins, a manual script tag, and Salesforce Lightning, and sends security alerts through webhook, S3, and Jira/Linear notification endpoints. cside publishes an llms.txt, a public read-only MCP server, and a Trust Center covering SOC 2 Type II, PCI SAQ-D, and ISO 27001.

c/side is profiled on the APIs.io network. Tagged areas include Company, Security, Client-Side Security, Application Security, and Fraud Prevention.

The c/side catalog on APIs.io includes 1 event-driven AsyncAPI specification.

c/side’s developer surface includes documentation, getting-started guide, engineering blog, pricing, signup flow, CLI, changelog, and 21 more developer resources.

40.9/100 thin ▬ flat Agent 24/100 agent aware Full breakdown ↓
scored 2026-07-27 · rubric v0.5
0 APIs 1 MCP Servers
CompanySecurityClient-Side SecurityApplication SecurityFraud PreventionPCI DSS ComplianceDevice FingerprintingBot DetectionWeb SecurityScript Monitoring

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 40.9/100 · thin
Contract Quality 5.7 / 25
Developer Ergonomics 11.3 / 20
Commercial Clarity 10.0 / 20
Operational Transparency 7.2 / 13
Governance 0.0 / 12
Discoverability 6.8 / 10
Agent readiness — 24/100 · agent aware
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 15
MCP Server 12 / 12
Machine-Readable Auth 0 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 4 / 4
Consent & Bot Identity 3 / 3
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/c-side: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

c-side-mcp.yml

MCP SERVER

Event Specifications 1

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

C Side Webhooks

ASYNCAPI

Security Posture 3

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

C Side Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

C Side Vulnerability Disclosure

security.txt · contact published

SECURITY

C Side Trust Center

SOC 2 Type II, PCI DSS (SAQ-D AOC), ISO 27001 (in progress), GDPR

SECURITY

Resources

Get Started 3

Portal, sign-up, and the first successful call

Documentation 1

Reference material describing how the API behaves

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

Design & Contract 4

Pagination, idempotency, versioning, errors, and events

Build 4

SDKs, sample code, and the tooling you integrate with

Access & Security 6

Authentication, authorization, and security posture

Operate 3

Status, limits, changes, and where to get help

Commercial 2

Pricing, plans, and the legal terms of use

Company 2

The organization behind the API

Source (apis.yml)

apis.yml Raw ↑
aid: c-side
name: c/side
description: c/side (cside) is a client-side security platform that detects script attacks, AI agents, account takeover, and
  fraud at the browser layer. It provides active runtime detection that watches what third-party scripts, users, and agents
  actually do as they execute in the live browser session, in real time, rather than relying on static scans or block-lists,
  and it automates PCI DSS 4.0.1 requirements 6.4.3 and 11.6.1 (validated by a VikingCloud QSA). cside deploys as a single
  JavaScript snippet with no proxy and no DNS changes, and was the first client-side security product with integrated AI analysis.
  The platform protects websites from malicious third-party scripts, e-skimming, Magecart, and supply chain attacks, and adds
  device fingerprinting (102+ signals), VPN/bot/AI-agent detection, chargeback evidence, and privacy monitoring for GDPR,
  CCPA, and HIPAA. Founded in 2024 and backed by Uncork Capital, cside integrates via a CLI, Next.js and Vite plugins, a manual
  script tag, and Salesforce Lightning, and sends security alerts through webhook, S3, and Jira/Linear notification endpoints.
  cside publishes an llms.txt, a public read-only MCP server, and a Trust Center covering SOC 2 Type II, PCI SAQ-D, and ISO
  27001.
url: https://raw.githubusercontent.com/api-evangelist/c-side/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- uncork-capital
x-tier: stub
x-tier-reason: portfolio-lead
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-18'
image: https://og.cside.com/?title=cside%2C%20Client-Side%20Security%20%26%20Browser%20Fraud%20Prevention
tags:
- Company
- Security
- Client-Side Security
- Application Security
- Fraud Prevention
- PCI DSS Compliance
- Device Fingerprinting
- Bot Detection
- Web Security
- Script Monitoring
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: https://cside.com
- type: DeveloperPortal
  url: https://docs.cside.com
- type: Documentation
  url: https://docs.cside.com
- type: GettingStarted
  url: https://docs.cside.com/quickstart
- type: Blog
  url: https://cside.com/blog
- type: Pricing
  url: https://cside.com/pricing
- type: SignUp
  url: https://dash.cside.com/auth/signup
- type: PrivacyPolicy
  url: https://cside.com/privacy-policy
- type: HelpCenter
  url: https://cside.com/faq
- type: GitHubOrganization
  url: https://github.com/client-side-dev
- type: MCPServer
  url: mcp/c-side-mcp.yml
- type: LLMsTxt
  url: llms/c-side-llms.txt
- type: Packages
  url: packages/c-side-packages.yml
- type: SDKs
  url: packages/c-side-packages.yml
- type: CLI
  url: cli/c-side-cli.yml
- type: Components
  url: components/c-side-components.yml
- type: WellKnown
  url: well-known/c-side-well-known.yml
- type: SecurityTxt
  url: well-known/c-side-security.txt
- type: Webhooks
  url: asyncapi/c-side-webhooks.yml
- type: ChangeLog
  url: changelog/c-side-changelog.yml
- type: Lifecycle
  url: lifecycle/c-side-lifecycle.yml
- type: StatusPage
  url: https://status.cside.com
- type: Conformance
  url: conformance/c-side-conformance.yml
- type: Compliance
  url: https://trust.cside.com
- type: TrustCenter
  url: security/c-side-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/c-side-vulnerability-disclosure.yml
- type: Security
  url: https://cside.com/security
- type: DomainSecurity
  url: security/c-side-domain-security.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence