KG-NINJA
KG-NINJA is the operator identity (GitHub user KG-NINJA, Osaka; Cloudflare Wallet handle @kgninja) behind Agent Verification Utility at agent-economy.kgninja.dev, a Cloudflare Workers service (v0.4.3) that runs bounded deterministic checks (SHA-256 equality, JSON Pointer existence/equality/type) over caller-supplied inline JSON and returns an Ed25519-signed execution record, sold to agents per call for 10000 atomic USDC ($0.01) on Base through x402 v2 with no account, API key or OAuth. One origin exposes the product three ways — a 44-operation OpenAPI 3.1.0 contract at /openapi.json, a remote Streamable HTTP MCP server at /mcp answering an anonymous tools/list (five tools, one paid), and an A2A 1.0 agent card at /.well-known/agent-card.json with JSON-RPC at /a2a — plus an RFC 9727 API catalog, an MCP Registry server.json, a provider-published Agent Skill, a JWKS, an x402 manifest, llms.txt and Content-Signal. The apex kgninja.dev has no A record; the subdomain is its only web presence.
KG-NINJA publishes 10 API contracts indexed on the APIs.io network, including A2a API, Decision Support API, Discovery API, and 7 more. Tagged areas include Agents, Agentic Commerce, A2A, MCP, and x402.
KG-NINJA’s developer surface includes authentication, documentation, getting-started guide, API reference, FAQ, pricing, sandbox, and 24 more developer resources.
What this lets a business do 1
Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →
Kin Score
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 |
|---|---|---|---|---|
| x402 Micropayments & Agentic Pay-per-Call | undeclared | - | 3 | 1 |
| Japan ISMAP Cloud Security Assessments (TISAX unreadable) | undeclared | - | 3 | 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 2
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.
APIs 10
Individual APIs this provider publishes, each with its own machine-readable definition.
Agent Verification Utility MCP Server
Remote Model Context Protocol server at https://agent-economy.kgninja.dev/mcp — stateless Streamable HTTP, POST only (GET returns 405), serverInfo dev.kgninja/agent-verification...
Agent Verification Utility A2A Agent
Agent2Agent (A2A) 1.0 surface: an agent card served from https://agent-economy.kgninja.dev/.well-known/agent-card.json (supportedInterfaces[] JSONRPC at https://agent-economy.kg...
KG-NINJA A2a API
Synchronous A2A 1.0 JSON-RPC quote preparation
KG-NINJA Decision Support API
Free use-case selection and request validation before payment
KG-NINJA Discovery API
Machine-readable service discovery
KG-NINJA Goals API
Goal-driven revenue measurement and improvement recommendations
KG-NINJA MCP API
Stateless MCP Streamable HTTP transport
KG-NINJA Operations API
Availability and operational status
KG-NINJA Purchase API
Quote and paid verification operations
KG-NINJA Registration API
Optional anonymous, short-lived agent registration
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MCP Servers 1
Model Context Protocol servers that expose these APIs to AI agents.
KG-NINJA MCP Server
KG-NINJA operates ONE remote MCP server at https://agent-economy.kgninja.dev/mcp — the same origin as its website, OpenAPI and A2A endpoint. It is stateless Streamable HTTP, POS...
MCP SERVERAgent Skills 1
Packaged agent skills for driving this provider's APIs from an AI assistant.
verify-json-evidence
AGENT SKILLPricing Plans 1
Published pricing tiers and plan structures.
Rate Limits 1
Documented rate limits and quota policies.
Kgninja Dev Rate Limits
RATE LIMITSOpenAPI 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.
Kgninja Dev Openapi Overlay
DERIVEDSecurity Posture 2
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Get Started 2
Portal, sign-up, and the first successful call
Documentation 2
Reference material describing how the API behaves
Agent Surfaces 7
MCP servers, agent skills, and machine-readable catalogs
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Design & Contract 6
Pagination, idempotency, versioning, errors, and events
Build 2
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 2
Pricing, plans, and the legal terms of use
Company 1
The organization behind the API
Other 5
Properties that don't map to a standard resource type
Source (apis.yml)
KG-NINJA API — frequently asked questions
Does KG-NINJA have an API?
Yes. APIs.io lists 10 APIs from KG-NINJA, including Agent Verification Utility MCP Server, Agent Verification Utility A2A Agent and KG-NINJA A2a API, and 7 more.
Is there an OpenAPI specification for the KG-NINJA API?
Yes. APIs.io indexes 8 OpenAPI specifications for KG-NINJA, each linked for download from this page.
How do I authenticate with the KG-NINJA API?
KG-NINJA uses bearer-token authentication (http · 1 scheme). The details are profiled on APIs.io as Kgninja Dev Authentication.
How much does the KG-NINJA API cost?
APIs.io lists 1 pricing plan for KG-NINJA, with each plan's price, limits and inclusions under Pricing Plans on this page.
Does KG-NINJA have an MCP server?
Yes. APIs.io lists 1 MCP server for KG-NINJA: KG-NINJA operates ONE remote MCP server at https://agent-economy.kgninja.dev/mcp — the same origin as its website, OpenAPI and A2A endpoint. It is stateless Streamable HTTP, POST only (GET returns 405
Is the KG-NINJA API ready for AI agents?
KG-NINJA has a Kin Score of 38.1 out of 100 (thin) and an Agent Readiness score of 53.9 (agent-native), scored by API Evangelist on 2026-10-31.
Work with this as data
Every provider here is available over the APIs.io API and to AI agents over MCP.