# Agent Verification Utility API

**Canonical:** https://apis.io/apis/kgninja-dev/agent-verification-utility-api/  
**Provider:** KG-NINJA — https://apis.io/providers/kgninja-dev/  
**Base URL:** /  
**Documentation:** https://agent-economy.kgninja.dev/

Agent Verification Utility API is one of 3 APIs that [KG-NINJA](https://apis.io/providers/kgninja-dev/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include Verification, JSON, x402, Agentic Commerce, and Agent-Native. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, an API reference, and a getting-started guide.

REST contract for the Agent Verification Utility: a free precheck (POST /validate-request) that binds a verification request and an explicit spend policy into an unsigned receipt, a free quote (POST /quote, Idempotency-Key required), and the paid execution route (POST /verify-evidence) that answers HTTP 402 with an x402 v2 PaymentRequired document and, on the paid retry, returns the deterministic result, Ed25519-signed evidence, a delivery receipt and a fulfillment proof. The remaining operations are discovery and operations surfaces — agent manifest, x402 manifest, RFC 9727 API catalog, AI catalog, MCP server card and registry document, Agent Skills index, JWKS, health, public stats, revenue goal — plus optional 15-minute anonymous agent registration. 44 operations, 47 component schemas, OpenAPI 3.1.0, served at https://agent-economy.kgninja.dev/openapi.json with servers[] "/" (relative to the deployment origin).

## Operations (44)

| Method | Path | Summary |
|---|---|---|
| GET | `/` | Get the human- and agent-readable service index |
| GET | `/auth.md` | Get agent registration, anonymous-access, and x402 guidance |
| POST | `/agent/register` | Provision an optional anonymous agent registration |
| GET | `/agent/registration` | Inspect the caller's anonymous registration claim |
| GET | `/.well-known/agent-card.json` | Get the A2A 1.0 Agent Card |
| POST | `/a2a` | Use the A2A 1.0 JSON-RPC interface |
| GET | `/.well-known/openapi.json` | Get the OpenAPI document from a well-known alias |
| GET | `/server.json` | Get the official MCP Registry publication document |
| GET | `/mcp/server.json` | Get the MCP Registry publication document beside the MCP endpoint |
| GET | `/.well-known/mcp-registry-auth` | Get the optional MCP Registry HTTP domain-ownership proof |
| GET | `/docs/deterministic-json-verification` | Read the deterministic JSON verification guide |
| GET | `/docs/reproducible-x402-receipts` | Read the x402 receipt and signed-evidence guide |
| GET | `/docs/mcp-x402-interoperability` | Read the MCP and x402 interoperability guide |
| GET | `/docs/security-and-trust` | Read the security, privacy, and trust-boundary guide |
| GET | `/faq` | Read machine-indexable answers about scope, payment, and trust |
| GET | `/webmcp.js` | Get the feature-detected browser WebMCP bridge |
| GET | `/12ffcf699b4a1cecdfe4f30a0bc795705169b8c87d475a49.txt` | Get the IndexNow host-ownership key |
| GET | `/verification-recipes.json` | Get deterministic verification use-case recipes |
| GET | `/.well-known/verification-recipes.json` | Get verification recipes from the well-known alias |
| POST | `/validate-request` | Validate a verification request for free without executing it |
| POST | `/quote` | Validate a request and quote deterministic verification |
| POST | `/verify-evidence` | Purchase and execute deterministic evidence verification |
| GET | `/health` | Get service liveness and availability |
| GET | `/stats` | Get privacy-safe service activity and readiness metrics |
| GET | `/goal` | Get the active revenue goal and next improvement |
| GET | `/.well-known/revenue-goal.json` | Get the revenue goal status from a well-known alias |
| GET | `/agent.json` | Get the product-specific agent service manifest |
| GET | `/.well-known/x402` | Get the self-hosted x402 convenience manifest |
| GET | `/.well-known/api-catalog` | Get the RFC 9727 API catalog |
| GET | `/.well-known/ai-catalog.json` | Discover the service and its decision-support entry points |
| GET | `/mcp/server-card` | Get the current experimental MCP Server Card |
| GET | `/.well-known/mcp/server-card.json` | Get the Cloudflare Agent Readiness MCP card |
| GET | `/.well-known/mcp.json` | Get the draft MCP Server Card compatibility alias |
| GET | `/.well-known/agent-skills/index.json` | Discover published Agent Skills |
| GET | `/.well-known/agent-skills/verify-json-evidence/SKILL.md` | Get the verify-json-evidence Agent Skill |
| GET | `/.well-known/jwks.json` | Get public keys for verification evidence |
| GET | `/llms.txt` | Get the compact LLM-oriented service index |
| GET | `/llms-full.txt` | Get complete LLM-oriented usage guidance |
| GET | `/index.md` | Get the canonical Markdown service guide |
| GET | `/icon.svg` | Get the service icon referenced by the MCP Server Card |
| GET | `/robots.txt` | Get crawler access policy and discovery hints |
| GET | `/sitemap.xml` | Get the public service discovery sitemap |
| GET | `/openapi.json` | Get this OpenAPI document |
| POST | `/mcp` | Stateless MCP SDK v2 Streamable HTTP endpoint |

## Machine-readable artifacts (10)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/openapi/kgninja-dev-openapi.json
- **OpenAPI** — https://agent-economy.kgninja.dev/openapi.json
- **Documentation** — https://agent-economy.kgninja.dev/docs/deterministic-json-verification
- **APIReference** — https://agent-economy.kgninja.dev/openapi.json
- **GettingStarted** — https://agent-economy.kgninja.dev/index.md
- **Overlay** — https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/overlays/kgninja-dev-openapi-overlay.yaml
- **Conventions** — https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/conventions/kgninja-dev-conventions.yml
- **ErrorCatalog** — https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/errors/kgninja-dev-problem-types.yml
- **DataModel** — https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/data-model/kgninja-dev-data-model.yml
- **APIsJSON** — https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/apis.yml

## Other KG-NINJA APIs (2)

- [Agent Verification Utility MCP Server](https://apis.io/apis/kgninja-dev/agent-verification-utility-mcp-server/)
- [Agent Verification Utility A2A Agent](https://apis.io/apis/kgninja-dev/agent-verification-utility-a2a-agent/)

## Tags

Verification, JSON, x402, Agentic Commerce, Agent-Native

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/kgninja-dev/agent-verification-utility-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/kgninja-dev/.