specification: API Evangelist Vocabulary
specificationVersion: '0.1'
provider: Arcade.dev
providerId: arcade-dev
created: '2026-05-25'
modified: '2026-05-25'
description: Vocabulary describing the Arcade.dev MCP / agent tool runtime surface — domain entities, operational
  axes, and AI-agent capabilities exposed by the Arcade Engine.
sources:
  - https://arcade.dev
  - https://docs.arcade.dev
  - https://api.arcade.dev/v1/swagger
domains:
  - id: agents-and-tools
    label: AI Agents and Tools
    description: Concepts related to AI agent tool calling, tool definition, and execution.
    terms:
      - id: tool
        label: Tool
        definition: A single named action that an AI agent can invoke, scoped to a toolkit and addressable by
          fully_qualified_name (Toolkit.Name@version).
        aliases: [agent-tool, mcp-tool]
        seeAlso:
          - https://docs.arcade.dev/home/tools
      - id: toolkit
        label: Toolkit
        definition: A versioned collection of related tools — usually mapped to one upstream SaaS provider
          (Google, Slack, Salesforce, GitHub, etc.).
      - id: tool-execution
        label: Tool Execution
        definition: A single invocation of a tool by user_id; the unit of metered usage in the Arcade billing
          model.
      - id: worker
        label: Worker
        definition: A process that hosts toolkits and is called by the Arcade Engine over HTTP (with shared
          secret) or via MCP transports.
      - id: gateway
        label: MCP Gateway
        definition: A scoped MCP endpoint, per organization and project, that exposes a curated catalog of
          tools to MCP clients (Cursor, Claude Desktop, VS Code).
  - id: identity-and-auth
    label: Identity and Authorization
    description: How Arcade ties tool invocations to specific end-users.
    terms:
      - id: user-id
        label: User ID
        definition: A stable identifier the caller supplies to indicate which end-user the tool call acts on
          behalf of. Required for any user-scoped tool.
      - id: authorization
        label: Authorization
        definition: A user-scoped grant tying user_id + provider_id + scopes to a live OAuth or API-key token
          managed by the Arcade Engine.
      - id: auth-provider
        label: Auth Provider
        definition: An external identity / OAuth provider that Arcade integrates with (Google, Microsoft,
          Slack, GitHub, Salesforce, HubSpot, and 40+ more).
      - id: user-challenge
        label: User Challenge
        definition: A prompt to an end-user to complete an OAuth or API-key grant. Used as a billing metric
          ($0.05 each above the included quota on the Growth plan).
  - id: governance
    label: Governance and Operations
    description: Operational, audit, and governance concepts.
    terms:
      - id: hook
        label: Hook
        definition: An HTTP destination that receives Arcade lifecycle events (tool_authorization,
          tool_execution, audit). Hooks are the primary integration point for SIEM and audit logging.
      - id: plugin
        label: Plugin
        definition: An extension that adds custom auth providers, transformers, or tool sources to the Arcade
          Engine.
      - id: scheduled-tool
        label: Scheduled Tool
        definition: A tool execution queued for a future run_at time.
      - id: audit-log
        label: Audit Log
        definition: A record of authorization grants and tool executions surfaced through hooks and the
          Arcade audit log feature.
  - id: deployment
    label: Deployment Topology
    description: Where the Arcade Engine and workers can run.
    terms:
      - id: arcade-cloud
        label: Arcade Cloud
        definition: Arcade-hosted SaaS deployment at api.arcade.dev.
      - id: arcade-vpc
        label: Arcade VPC
        definition: Single-tenant Arcade Engine deployed into a customer's cloud VPC.
      - id: arcade-on-prem
        label: Arcade On-Prem / Air-Gapped
        definition: Self-hosted Arcade Engine, including air-gapped installations.
      - id: hosted-mcp-server
        label: Hosted MCP Server
        definition: Arcade-managed MCP server running 24/7 ($0.05/hour above the Hobby allotment).
      - id: self-hosted-worker
        label: Self-Hosted Worker
        definition: Customer-run worker reached over HTTP with a shared secret, used to keep tool execution
          (and end-user tokens) inside the customer's perimeter.
tags:
  - AI
  - Agents
  - Tools
  - MCP
  - OAuth
  - Authorization
  - Identity
  - Governance