HaneruTo

HaneruTo — trading as hakuto, brand B612 SHEEP — is a Japanese one-person, AI-assisted web and systems development studio founded in 2025 that also ships b612, a Japanese-market code-review agent for AI coding assistants: review checklists by target type, industry presets with mandatory Japanese legal checkpoints (景表法 / 特商法 / 薬機法 / インボイス / 電帳法 / 宅建業法 / 介護保険法), failure patterns and 31 deterministic detection rules — no LLM involved; the server has no input for customer source code. b612 is published two ways on mcp.hakuto-0209.com: a remote MCP server at /mcp (Streamable HTTP, protocol 2025-06-18, ten tools with real inputSchemas, anonymous tools/list, keyless principles/rules) and an A2A 0.3 agent whose EdDSA-signed card at /.well-known/agent-card.json declares six skills behind an x-b612-key licence header, with the signing key at /.well-known/jwks.json. No REST/OpenAPI surface, no SDK, no self-serve sign-up; agent access is a monthly flat-fee licence priced on contact.

HaneruTo is listed with 2 APIs on the APIs.io network. Tagged areas include Agents, MCP, A2A, Code Review, and Static Analysis.

HaneruTo’s developer surface includes documentation, pricing, support, authentication, and 18 more developer resources.

🌐 Visit website 📡 Source on GitHub
30.0/100 thin ▬ flat Agent 19/100 agent aware Front door AI 4/6 moderate Full breakdown ↓
scored 2026-10-09 · rubric v0.23.0
2 APIs 1 MCP Servers
AgentsMCPA2ACode ReviewStatic AnalysisDeveloper ToolsComplianceWeb DevelopmentJapanAgent-Native

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-10-09 · rubric v0.23.0
Composite quality — 30.0/100 · thin
Contract Quality 0.0 / 21
Developer Ergonomics 4.5 / 17
Access Clarity 8.9 / 17
Operational Transparency 2.3 / 11
Contract Governance 1.9 / 10
Discoverability 5.8 / 9
Regulatory Posture 4.9 / 15
Agent readiness — 19/100 · agent aware
Machine-Readable Contract 0 / 18
Agentic Access Contract 10 / 10
Documented Reversibility 0 / 6
MCP Server 12 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 8 / 8
Dry-Run / Simulate Mode 0 / 4
Delegated User Identity 0 / 6
Protected Resource Metadata 0 / 5
Registration Without a Human 0 / 6
Agentic Commerce Well-Known Document 0 / 5
Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.
Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.
The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/hakuto-0209-com: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 2

Individual APIs this provider publishes, each with its own machine-readable definition.

b612 MCP Server

Remote Model Context Protocol server at https://mcp.hakuto-0209.com/mcp (Streamable HTTP, POST only — GET returns 406 — protocol version 2025-06-18, serverInfo b612 0.1.0, hoste...

b612 A2A Agent

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, pro...

MCP Servers 1

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

HaneruTo MCP Server

HaneruTo operates ONE remote MCP server, b612, at https://mcp.hakuto-0209.com/mcp — the same host that serves its A2A agent card and JSON-RPC endpoint (Vercel origin b612-a2a.ve...

MCP SERVER

Pricing Plans 1

Published pricing tiers and plan structures.

Hakuto 0209 Com Plans Pricing

2 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Hakuto 0209 Com Rate Limits

1 limits

RATE LIMITS

Security Posture 2

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

Hakuto 0209 Com Authentication

apiKey · 1 scheme

SECURITY

Hakuto 0209 Com Domain Security

TLSv1.3 · HSTS

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Hakuto 0209 Com Agentic Access

16 operations

16 operations · 0 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

MCPServer
MCPServer
 WellKnown
WellKnown
 LLMsTxt
LLMsTxt
 AgenticAccess
AgenticAccess

Design & Contract 4

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 ErrorCatalog
ErrorCatalog
 Conformance
Conformance
 Lifecycle
Lifecycle

Access & Security 2

Authentication, authorization, and security posture

Authentication
Authentication
 DomainSecurity
DomainSecurity

Operate 2

Status, limits, changes, and where to get help

Support
Support
 RateLimits
RateLimits

Commercial 4

Pricing, plans, and the legal terms of use

Pricing
Pricing
 TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy
 Plans
Plans

Company 1

The organization behind the API

Website
Website

Other 4

Properties that don't map to a standard resource type

AgentCard
AgentCard
 AITransparency
AITransparency
 DataSubjectRequest
DataSubjectRequest
 Subprocessors
Subprocessors

Source (apis.yml)

apis.yml Raw ↑ 
aid: hakuto-0209-com
name: HaneruTo
description: 'HaneruTo — trading as hakuto, brand B612 SHEEP — is a Japanese one-person, AI-assisted web and systems development
  studio founded in 2025 that also ships b612, a Japanese-market code-review agent for AI coding assistants: review checklists
  by target type, industry presets with mandatory Japanese legal checkpoints (景表法 / 特商法 / 薬機法 / インボイス / 電帳法 / 宅建業法 / 介護保険法),
  failure patterns and 31 deterministic detection rules — no LLM involved; the server has no input for customer source code.
  b612 is published two ways on mcp.hakuto-0209.com: a remote MCP server at /mcp (Streamable HTTP, protocol 2025-06-18, ten
  tools with real inputSchemas, anonymous tools/list, keyless principles/rules) and an A2A 0.3 agent whose EdDSA-signed card
  at /.well-known/agent-card.json declares six skills behind an x-b612-key licence header, with the signing key at /.well-known/jwks.json.
  No REST/OpenAPI surface, no SDK, no self-serve sign-up; agent access is a monthly flat-fee licence priced on contact.'
image: https://hakuto-0209.com/assets/og.png
url: https://raw.githubusercontent.com/api-evangelist/hakuto-0209-com/refs/heads/main/apis.yml
x-type: company
x-source: harvest:a2a-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-09-19 (local-v3; was a2a-registry harvest stub)
specificationVersion: '0.20'
created: '2026-09-19'
modified: '2026-09-19'
tags:
- Agents
- MCP
- A2A
- Code Review
- Static Analysis
- Developer Tools
- Compliance
- Web Development
- Japan
- Agent-Native
tags_raw:
- Agents
- MCP
- A2A
- Code review
- Static analysis
- Developer tools
- Compliance
- Web development
- Japan
- Agent-native
- agent-native
apis:
- aid: hakuto-0209-com:b612-mcp-server
  name: b612 MCP Server
  description: 'Remote Model Context Protocol server at https://mcp.hakuto-0209.com/mcp (Streamable HTTP, POST only — GET
    returns 406 — protocol version 2025-06-18, serverInfo b612 0.1.0, hosted on Vercel). initialize and tools/list answer
    anonymously with ten tools, every one carrying a real inputSchema and execution.taskSupport "forbidden": b612_principles,
    b612_review_checklist, b612_patterns, b612_domain_preset, b612_rules, b612_design, b612_reference, b612_grow, b612_notes
    and b612_update. b612_principles was also callable without a key; the provider''s quickstart configures the connection
    with an x-b612-key licence header (`claude mcp add --transport http b612 https://mcp.hakuto-0209.com/mcp --header "x-b612-key:
    <your key>"`). resources/list and prompts/list return -32601. The initialize instructions tell the agent to apply checklists
    and rules to code locally — no source code is sent to the server.'
  humanURL: https://mcp.hakuto-0209.com/
  baseURL: https://mcp.hakuto-0209.com/mcp
  tags:
  - MCP
  - Agent-Native
  - Code Review
  tags_raw:
  - MCP
  - agent-native
  - Code Review
  properties:
  - type: MCPServer
    url: mcp/hakuto-0209-com-mcp.yml
  - type: MCPServer
    name: b612 MCP endpoint (Streamable HTTP)
    url: https://mcp.hakuto-0209.com/mcp
  - type: Documentation
    url: https://mcp.hakuto-0209.com/
- aid: hakuto-0209-com:b612-a2a-agent
  name: b612 A2A Agent
  description: '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.'
  humanURL: https://mcp.hakuto-0209.com/
  baseURL: https://mcp.hakuto-0209.com/a2a/v1
  tags:
  - A2A
  - Agent-Native
  - Code Review
  tags_raw:
  - A2A
  - agent-native
  - Code Review
  properties:
  - type: AgentCard
    url: a2a/hakuto-0209-com-a2a.yml
  - type: AgentCard
    name: A2A Agent Card (provider-hosted, signed)
    url: https://mcp.hakuto-0209.com/.well-known/agent-card.json
  - type: Documentation
    url: https://mcp.hakuto-0209.com/terms
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: https://hakuto-0209.com/
- type: Documentation
  url: https://mcp.hakuto-0209.com/
- type: Pricing
  name: Company information and 特定商取引法 price disclosure (development service; agent licence priced on contact)
  url: https://hakuto-0209.com/legal/hakuto-company.html
- type: TermsOfService
  url: https://hakuto-0209.com/legal/hakuto-terms.html
- type: PrivacyPolicy
  url: https://hakuto-0209.com/legal/hakuto-privacy.html
- type: Support
  url: https://hakuto-0209.com/#contact
- type: AgentCard
  url: a2a/hakuto-0209-com-a2a.yml
- type: MCPServer
  url: mcp/hakuto-0209-com-mcp.yml
- type: WellKnown
  url: well-known/hakuto-0209-com-well-known.yml
- type: LLMsTxt
  url: llms/hakuto-0209-com-llms.txt
- type: Authentication
  url: authentication/hakuto-0209-com-authentication.yml
- type: Conventions
  url: conventions/hakuto-0209-com-conventions.yml
- type: ErrorCatalog
  url: errors/hakuto-0209-com-problem-types.yml
- type: RateLimits
  url: rate-limits/hakuto-0209-com-rate-limits.yml
- type: Plans
  url: plans/hakuto-0209-com-plans-pricing.yml
- type: Conformance
  url: conformance/hakuto-0209-com-conformance.yml
- type: Lifecycle
  url: lifecycle/hakuto-0209-com-lifecycle.yml
- type: AgenticAccess
  url: agentic-access/hakuto-0209-com-agentic-access.yml
- type: DomainSecurity
  url: security/hakuto-0209-com-domain-security.yml
- type: AITransparency
  url: https://mcp.hakuto-0209.com/terms
- type: DataSubjectRequest
  url: https://mcp.hakuto-0209.com/terms
- type: Subprocessors
  url: https://mcp.hakuto-0209.com/terms
x-enrichment:
  date: '2026-09-19'
  status: enriched
  artifacts_added: 18
  pass: local-v3
x-a2a:
  verified: true
  probed: '2026-09-26'
  url: https://mcp.hakuto-0209.com/.well-known/agent-card.json
  grade: conformant
  protocol_version: '0.3'
  control: 404

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for providers

9 MCP tools reach this
  • find_providersBrowse and filter every provider in the catalog.
  • get_provider_artifactsEvery artifact this provider publishes, grouped by type.
  • get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
  • get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
  • get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
  • get_provider_ratingPRO — composite, band, trend and facet scores.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools →

Call it yourself

curl for this page
This provider 
curl "https://apis.io/api/v1/providers/hakuto-0209-com"
All providers 
curl "https://apis.io/api/v1/providers?limit=25"
Every operation they expose 
curl "https://apis.io/api/v1/providers/hakuto-0209-com/operations?limit=25"
How their score was established 
curl "https://apis.io/api/v1/providers/hakuto-0209-com/evidence"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.