generated: '2026-09-19'
method: probed
source: https://publicdata-agent.songt50.us/.well-known/agent.json
notes: >-
  sapjilcoding (삽질코딩 — the maker brand of Song Tae-Eun, GitHub SongT-50, MCPize handle higheun) serves TWO A2A
  Agent Cards from two subdomains of its own registrable domain songt50.us. Both are live, anonymous JSON-RPC
  agents: the Korean Public Data Agent (weather, air quality, apartment prices, Bank of Korea statistics, business
  registration checks) at publicdata-agent.songt50.us and the Korean News Agent (Korean and global tech news, keyword
  search, trending, daily briefing — "Powered by Korean News MCP") at news-agent.songt50.us. Each host serves the
  identical document at BOTH the canonical /.well-known/agent-card.json and the legacy /.well-known/agent.json;
  every other /.well-known/ path on those hosts returns a 9-byte text/plain "Not Found" 404, so the 200s are served
  documents and not a catch-all. The apex songt50.us answers Cloudflare 522 (origin unreachable) on every path and
  www.songt50.us does not resolve, so the agent subdomains are the provider's only reachable web surface. Ownership
  is not in question: provider.organization is "sapjilcoding" in both cards, provider.url is the serving host, the
  a2aregistry.org records name the author sapjilcoding, and the companion GitHub repositories carry LICENSE
  "Copyright (c) 2026 sapjil-coding" and credit the 삽질코딩 YouTube channel.
discovery:
  path: /.well-known/agent.json
  canonical: false
  host: publicdata-agent.songt50.us
  note: >-
    Recorded at the legacy path because that is the wellKnownURI the provider registered on a2aregistry.org (the
    lead this profile came from) and the first URL fetched; the canonical /.well-known/agent-card.json serves a
    byte-identical document on both hosts (2,284 and 2,007 bytes respectively).
card:
  name: Korean Public Data Agent
  url: https://publicdata-agent.songt50.us
  version: 1.0.0
  skills: 5
  file: songt50-us-agent-card.json
cards:
- file: songt50-us-agent-card.json
  primary: true
  host: publicdata-agent.songt50.us
  url: https://publicdata-agent.songt50.us/.well-known/agent.json
  canonical_url: https://publicdata-agent.songt50.us/.well-known/agent-card.json
  http_status: 200
  content_type: application/json
  body_bytes: 2284
  name: Korean Public Data Agent
  agent_url: https://publicdata-agent.songt50.us
  protocol_version: 0.3.0
  preferred_transport: JSONRPC
  version: 1.0.0
  grade: conformant
  checks:
    capabilities_is_object: true
    protocol_version_present: true
    skills_is_array: true
    preferred_transport_present: true
    default_input_modes_present: true
    default_output_modes_present: true
  capabilities:
    streaming: false
    pushNotifications: false
    stateTransitionHistory: false
  security: none declared (no securitySchemes / security in the card; JSON-RPC answered anonymously)
  skills:
  - {id: weather, name: Korea Weather Forecast, tags: [weather, forecast, korea, temperature]}
  - {id: air_quality, name: Korea Air Quality, tags: [air, quality, pm25, pollution, korea]}
  - {id: real_estate, name: Korea Apartment Prices, tags: [real-estate, apartment, price, korea, property]}
  - {id: economic_stats, name: Korea Economic Statistics, tags: [economy, statistics, interest-rate, exchange-rate, kospi]}
  - {id: business_check, name: Business Registration Check, tags: [business, registration, verification, korea]}
- file: songt50-us-news-agent-card.json
  primary: false
  host: news-agent.songt50.us
  url: https://news-agent.songt50.us/.well-known/agent.json
  canonical_url: https://news-agent.songt50.us/.well-known/agent-card.json
  http_status: 200
  content_type: application/json
  body_bytes: 2007
  name: Korean News Agent
  agent_url: https://news-agent.songt50.us
  protocol_version: 0.3.0
  preferred_transport: JSONRPC
  version: 1.0.0
  grade: conformant
  checks:
    capabilities_is_object: true
    protocol_version_present: true
    skills_is_array: true
    preferred_transport_present: true
    default_input_modes_present: true
    default_output_modes_present: true
  capabilities:
    streaming: false
    pushNotifications: false
    stateTransitionHistory: false
  security: none declared (no securitySchemes / security in the card; JSON-RPC answered anonymously)
  skills:
  - {id: korean_news, name: Korean News Search, tags: [news, korean, search, korea]}
  - {id: tech_news, name: Global Tech News, tags: [tech, ai, global, trends]}
  - {id: news_search, name: Keyword News Search, tags: [search, keyword, query]}
  - {id: trending, name: Trending Headlines, tags: [trending, headlines, breaking]}
  - {id: daily_briefing, name: Daily News Briefing, tags: [briefing, daily, summary]}
conformance:
  spec: A2A 1.0.0
  grade: conformant
  protocol_version: 0.3.0
  preferred_transport: JSONRPC
  hard_checks:
    capabilities_is_object: true
    protocol_version_present: true
    skills_is_array: true
  optional_fields:
    preferred_transport: true
    default_input_modes: true
    default_output_modes: true
  grade_basis: >-
    Both cards pass all three hard checks — capabilities is an OBJECT (streaming, pushNotifications,
    stateTransitionHistory), protocolVersion is present ("0.3.0"), skills is an ARRAY (5 fully populated skills each,
    with id, name, description, tags, examples, inputModes and outputModes) — and carry every optional field the
    grade looks for (preferredTransport JSONRPC, defaultInputModes and defaultOutputModes text/plain). Both hosts
    are live JSON-RPC 2.0 responders: tasks/get for an unknown id returns the A2A-defined -32001 "Task not found";
    agent/getAuthenticatedExtendedCard returns -32603 "Authenticated card not supported", consistent with no
    extended card being declared. a2aregistry.org's own validator also reports conformance true for both.
  deviations:
  - field: protocolVersion
    observed: '0.3.0'
    note: The card is written to the 0.3.x shape (top-level url + preferredTransport); it declares no additionalInterfaces and is not declared against A2A 1.0.0. No hard check fails.
  - field: securitySchemes / security
    observed: absent on both cards
    note: Anonymous access is the actual behaviour (probed), so the omission is accurate rather than misleading; an agent cannot learn any quota or abuse policy from the card because none is published.
  - field: documentationUrl / iconUrl
    observed: absent
    note: No human documentation is linked from either card; the nearest provider-authored documentation is the companion GitHub repository README for each data surface.
  - field: url
    observed: the host root (https://publicdata-agent.songt50.us, https://news-agent.songt50.us)
    note: The JSON-RPC endpoint is the origin itself; a GET on it returns 405 Method Not Allowed (text/plain).
  - field: message/send task conformance
    observed: not exercised by this pipeline; a2aregistry.org's task_conformance check on 2026-09-19 recorded category TIMEOUT (16.3 s) for both agents, while its maintainer note says "Verified working. Agent responds to message/send correctly via the A2A SDK."
    note: Third-party observation recorded because it bears on whether a stock client completes a task; the registry also reports 24-hour uptime of 39% for both agents on 2026-09-20. API Evangelist sent no message.
x-evidence:
  fetched: '2026-09-19'
  url: https://publicdata-agent.songt50.us/.well-known/agent.json
  http_status: 200
  content_type: application/json
  body_bytes: 2284
  body_parses_as: JSON object with AgentCard shape (capabilities, defaultInputModes, defaultOutputModes, description, name, preferredTransport, protocolVersion, provider, skills, url, version)
  corroborating_probes:
  - {url: https://publicdata-agent.songt50.us/.well-known/agent-card.json, http_status: 200, note: byte-identical to the legacy path}
  - {url: https://news-agent.songt50.us/.well-known/agent.json, http_status: 200, content_type: application/json, body_bytes: 2007}
  - {url: https://news-agent.songt50.us/.well-known/agent-card.json, http_status: 200, note: byte-identical to the legacy path}
  - {url: https://publicdata-agent.songt50.us/.well-known/security.txt, http_status: 404, note: 9-byte text/plain "Not Found" — the host's real 404, so the agent card 200 is a served document, not a catch-all}
  - {url: https://publicdata-agent.songt50.us/, method: GET, http_status: 405, note: Method Not Allowed; the JSON-RPC endpoint is POST-only}
  - {url: https://publicdata-agent.songt50.us/, method: POST, body: '{"jsonrpc":"2.0","id":1,"method":"tasks/get","params":{"id":"apievangelist-nonexistent-probe"}}', http_status: 200, response: '{"error":{"code":-32001,"message":"Task not found"},"id":1,"jsonrpc":"2.0"}', note: A real A2A JSON-RPC responder; no message was sent}
  - {url: https://publicdata-agent.songt50.us/, method: POST, body: '{"jsonrpc":"2.0","id":1,"method":"agent/getAuthenticatedExtendedCard"}', http_status: 200, response: '{"error":{"code":-32603,"message":"Authenticated card not supported"},"id":1,"jsonrpc":"2.0"}'}
  - {url: https://news-agent.songt50.us/, method: POST, body: '{"jsonrpc":"2.0","id":1,"method":"tasks/get","params":{"id":"apievangelist-nonexistent-probe"}}', http_status: 200, response: '{"error":{"code":-32001,"message":"Task not found"},"id":1,"jsonrpc":"2.0"}'}
  - {url: https://songt50.us/.well-known/agent-card.json, http_status: 522, note: Cloudflare 522 origin unreachable on every apex path across three retries; www.songt50.us has no DNS record}
  - {url: https://a2aregistry.org/api/agents/13b680b9-0053-4b51-8e21-7f19df99cafc, http_status: 200, note: registry record for the Korean Public Data Agent (created 2026-03-07, author sapjilcoding, wellKnownURI the legacy agent.json path, conformance true, uptime 39% / is_healthy true on 2026-09-20)}
  - {url: https://a2aregistry.org/api/agents/44041f0f-6d82-410c-bc9f-4e0755b123f4, http_status: 200, note: registry record for the Korean News Agent (created 2026-03-07, same author and health profile)}
surface_relationship:
  note: >-
    The two agents are conversational fronts over the same data the provider ships as four open-source MCP servers
    (github.com/SongT-50/korean-public-data-mcp, korean-news-mcp, korean-stock-mcp, korean-agriculture-mcp; see
    mcp/songt50-us-mcp.yml). The public-data agent's five skills map one-to-one onto the public-data MCP server's
    five data tools (weather, air quality, real-estate trades, economic stats, business registration), and the news
    agent's five skills onto five of the six news MCP tools (read_article has no A2A skill). The A2A hosts on
    songt50.us were live on 2026-09-19; the four hosted MCP endpoints on onrender.com were all suspended (503,
    x-render-routing: suspend). No OpenAPI, GraphQL, AsyncAPI, gRPC or SOAP contract is published anywhere.