# b612 A2A Agent

**Canonical:** https://apis.io/apis/hakuto-0209-com/b612-a2a-agent/  
**Provider:** HaneruTo — https://apis.io/providers/hakuto-0209-com/  
**Base URL:** https://mcp.hakuto-0209.com/a2a/v1  
**Documentation:** https://mcp.hakuto-0209.com/

b612 A2A Agent is one of 2 APIs that [HaneruTo](https://apis.io/providers/hakuto-0209-com/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include A2A, agent-native, and Code Review. The published artifact set on APIs.io includes API documentation.

Agent2Agent (A2A) protocol surface: an agent card served from https://mcp.hakuto-0209.com/.well-known/agent-card.json (protocolVersion 0.3, JSONRPC transport, version 0.1.0, provider.organization HaneruTo) advertising six skills — principles, review-checklist, patterns, domain-preset, scan-code and rules — invoked as plain-text messages at the JSON-RPC endpoint https://mcp.hakuto-0209.com/a2a/v1 under an x-b612-key licence header (unkeyed requests get a 401 `unauthenticated` envelope whose hint names principles and rules as keyless, 20 req/min per IP). The card carries an EdDSA JWS signature that verifies against the JWKS at /.well-known/jwks.json (kid b612-a2a-2026-09) and is also served unsigned at the legacy /.well-known/agent.json. Streaming and push notifications are declared unsupported.

## Machine-readable artifacts (3)

- **AgentCard** — https://raw.githubusercontent.com/api-evangelist/hakuto-0209-com/refs/heads/main/a2a/hakuto-0209-com-a2a.yml
- **AgentCard** — https://mcp.hakuto-0209.com/.well-known/agent-card.json
- **Documentation** — https://mcp.hakuto-0209.com/terms

## Other HaneruTo APIs (1)

- [b612 MCP Server](https://apis.io/apis/hakuto-0209-com/b612-mcp-server/)

## Tags

A2A, agent-native, Code Review

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/hakuto-0209-com/b612-a2a-agent/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/hakuto-0209-com/.