# KG-NINJA

**Canonical:** https://apis.io/providers/kgninja-dev/  
**Website:** https://agent-economy.kgninja.dev/  
**APIs profiled:** 2

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.

## Kin Score — 37.7 / 100 (thin)

Scored 2026-10-09 under rubric 0.23.0. Trend: flat (+0.0 from 37.7).

| Facet | Score |
|---|---|
| Discoverability | 75.0 |
| Contract Quality | 42.2 |
| Contract Governance | 18.2 |
| Operational Transparency | 5.3 |
| Developer Ergonomics | 54.8 |
| Access Clarity | 31.6 |

Regulatory layer — **Horizontal (data, software, accessibility, platform)**: 16.7 (matched via fallback).

## Agent readiness — 54.9 (agent-native)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | documented |
| Auth Clarity | bearer |
| Idempotency | verified |
| Error Semantics | verified |
| OpenAPI Examples | partial |
| Rate Limit Signal | verified |
| Event Surface Described | no |
| Agent Skills | yes |
| Well Known Catalog | yes |
| Consent Identity | yes |
| Agent Card | conformant |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |

## APIs (10)

- **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

## MCP servers (1)

- **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...

## Agentic access (1)

- **Kgninja Dev Agentic Access** — 44 operations · 6 acting

## Security (2)

- **Kgninja Dev Authentication** — http · 1 scheme
- **Kgninja Dev Domain Security** — TLSv1.3 · HSTS · DNSSEC

## Plans (1)

- **Kgninja Dev Plans Pricing**

## Tags

Agents, Agentic Commerce, A2A, MCP, x402, Verification, JSON, Cryptography, Cloudflare Workers, Agent-Native, Japan

---

Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/kgninja-dev/). Scores are computed from the provider's own public artifacts under a published rubric.