generated: '2026-08-22'
method: probed
source: https://mcp.oe.horizon.auto/mcp
name: Open Explorer MCP Server
description: >-
  Horizon Robotics' hosted Model Context Protocol server for the OpenExplorer (OE)
  toolchain. It gives a coding agent semantic retrieval over Horizon's indexed
  codebases (Milvus-backed) and the Horizon documentation library, so an agent can
  locate an implementation, a configuration entry point or a manual passage before
  it acts. Advertised by Horizon Robotics in the install instructions of its own
  OE-Skills repository.
status: live
deployment:
  mode: remote
  endpoint: https://mcp.oe.horizon.auto/mcp
  transport: streamable-http
  auth: none
  verified: probed
protocol:
  spec: Model Context Protocol
  version: '2025-06-18'
  server_info:
    name: Open Explorer MCP Server
    version: 3.9.0
  capabilities:
    tools: true
    resources: true
    prompts: false            # prompts/list returns JSON-RPC -32601 Method not found
tool_count: 4
tools:
- name: list_codebases
  summary: List the codebases / Milvus collections currently indexed and available as search scope.
  read_only: true
  idempotent: true
  required_params: []
- name: search_code
  summary: Semantic natural-language search across indexed Horizon codebases, optionally scoped to named collections.
  read_only: true
  idempotent: true
  required_params: [query]
- name: search_doc
  summary: Semantic search of Horizon document snippets — manuals, guides, references. Defaults to the `oe_doc` library.
  read_only: true
  idempotent: true
  required_params: [query]
- name: get_doc
  summary: Read the full content overview of a document by docId, normally after search_doc returns one.
  read_only: true
  idempotent: true
  required_params: [path, docId]
resource_count: 3
resources:
- uri: openexplorer://mcp/overview
  name: openexplorer_overview
  mime: text/markdown
- uri: openexplorer://mcp/tools
  name: openexplorer_tool_catalog
  mime: text/markdown
- uri: openexplorer://mcp/agent-guide
  name: openexplorer_agent_guide
  mime: text/markdown
install:
  claude_code: claude mcp add --transport http oe-mcp https://mcp.oe.horizon.auto/mcp
  codex: codex mcp add oe-mcp --url https://mcp.oe.horizon.auto/mcp
  generic_config: |
    {"mcpServers": {"oe-mcp": {"type": "http", "url": "https://mcp.oe.horizon.auto/mcp"}}}
  documented_at: https://github.com/HorizonRobotics/OE-Skills/blob/main/README.en.md
files:
- horizon-robotics-mcp-tools.json      # verbatim tools/list result
- horizon-robotics-mcp-resources.json  # verbatim resources/list result
x-evidence:
  fetched: '2026-08-22'
  probes:
  - method: initialize
    url: https://mcp.oe.horizon.auto/mcp
    http_status: 200
    content_type: text/event-stream
    result: protocolVersion 2025-06-18, serverInfo "Open Explorer MCP Server" 3.9.0
  - method: tools/list
    url: https://mcp.oe.horizon.auto/mcp
    http_status: 200
    result: 4 tools with full inputSchema, saved verbatim
  - method: resources/list
    url: https://mcp.oe.horizon.auto/mcp
    http_status: 200
    result: 3 resources
  - method: prompts/list
    url: https://mcp.oe.horizon.auto/mcp
    http_status: 200
    result: 'JSON-RPC error -32601 Method not found'
  - url: https://mcp.oe.horizon.auto/.well-known/oauth-protected-resource
    http_status: 404
  notes: >-
    No Authorization header, session id or client registration was needed; the server
    answered anonymous POSTs from a plain curl. Every tool carries MCP annotations
    readOnlyHint:true, destructiveHint:false, idempotentHint:true — the server exposes
    no write surface.