FACT COPY · EN
Fact copy: MCP glossary
Definitions for MCP, agents and travel integration.
Canonical source: https://travel-mcp.com/en/knowledge/glossary/
Factual summary
The glossary provides consistent definitions and links to deeper knowledge pages.
Protocol roles
A host is the AI application and policy boundary. It normally creates one MCP client for each server connection. A server exposes negotiated capabilities; it is not the language model or automatically the downstream system of record.
- Host — user-facing application and orchestration boundary
- Client — one stateful protocol relationship to one server
- Server — provider of tools, resources or prompts
- Capability negotiation — runtime agreement about optional features
Capability primitives
Tools are model-invoked operations, resources are application-controlled context addressed by URI, and prompts are user-selected templates. These interaction models have different control and security expectations.
- Tool — structured invocation that may have side effects
- Resource — readable context with read-time authorization
- Prompt — user-controlled reusable interaction template
- Schema — structural contract, not proof of business validity
Travel-domain terms
Offer, order, reservation, PNR, ticket, EMD and itinerary are not synonyms. Their precise meaning depends on the supplier and standard; a knowledge system must preserve namespace, source and version.
- Offer — time-bound commercial proposition
- Order — commercial record governed by the provider
- PNR — reservation record locator and associated data
- Ticket/EMD — fulfilment and service documents in airline processes
Security and operations
Authentication establishes a subject; authorization decides a permitted action on a specific object. Consent, idempotency, provenance and auditability address different risks and cannot replace one another.
- Audience — resource for which a token is intended
- Least privilege — minimum capability and data access
- Idempotency — protection against duplicate state changes
- Provenance — documented origin and retrieval context