FACT COPY · EN
Fact copy: API and MCP: systematic comparison
Compares REST, GraphQL, SOAP and MCP across semantics, discovery, interaction, authorization, state and operations.
Canonical source: https://travel-mcp.com/en/research/api-mcp-comparison/
Factual summary
MCP is not an alternative to every API. Reliable architectures often place MCP over existing APIs as a standardized interaction layer for AI applications.
Specifications and core data
- REST
- Architekturstil
- GraphQL
- Abfragesprache und Laufzeit
- SOAP
- XML-Nachrichtenprotokoll
- MCP
- zustandsbehaftetes Capability-Protokoll auf JSON-RPC
- Kernergebnis
- komplementär statt pauschal ersetzend
Comparison matrix
| Criterion | REST | GraphQL | SOAP | MCP |
|---|---|---|---|---|
| Primary purpose | resource interaction | typed query/mutation | contractual XML messaging | AI capability/context access |
| Travel semantics | Requires a domain model; none is supplied automatically | |||
These technologies occupy different abstraction levels and are frequently complementary.
Decision boundary
Direct APIs may remain simpler for deterministic system-to-system integration. MCP is most plausible where AI hosts need reusable capability discovery and controlled invocation.
Research question and boundary
API and MCP: systematic comparison examines compares REST, GraphQL, SOAP and MCP across semantics, discovery, interaction, authorization, state and operations. The module distinguishes normative MCP requirements from editorial travel-architecture patterns. A pattern is not presented as protocol behaviour unless the versioned specification supports that claim.
The analysis also separates interoperability from suitability. A server may exchange valid MCP messages and still be unsafe, semantically ambiguous or unusable for a production travel process.
Travel-domain validity
Travel evidence must preserve the authoritative source, retrieval time, identifier namespace, currency, conditions and validity window. Offer, order, reservation, PNR, ticket, EMD and itinerary describe different states and must not be collapsed into a generic booking object.
For write operations, the test model includes repricing or state revalidation, object-level authorization, approval bound to the exact material terms, idempotency and recovery after a partial downstream failure. MCP supplies none of these domain guarantees automatically.
Method, falsification and evidence
The recorded indicators for this module include REST: Architekturstil; GraphQL: Abfragesprache und Laufzeit; SOAP: XML-Nachrichtenprotokoll; MCP: zustandsbehaftetes Capability-Protokoll auf JSON-RPC; Kernergebnis: komplementär statt pauschal ersetzend. Each claim should identify its observation date and primary source. Release candidates, experimental capabilities and editorial inferences are labelled separately from the current protocol baseline.
A useful result must survive counterexamples: unsupported client capabilities, malformed or adversarial content, stale supplier state, denied authorization, timeout and duplicate execution. The evidence package combines contract tests, negative tests, trace correlation and a documented owner for corrections.
Interpretation for decision-makers
The module is not a product ranking or an assurance certificate. Registry presence, repository activity or a successful demonstration cannot prove security, legal authority, commercial access or operational maturity.
A decision should state which uncertainty the module reduced, which assumptions remain open and what would falsify the conclusion. This prevents an interactive graphic or catalogue entry from being mistaken for production due diligence.