---
description: High-level architecture diagram for Model Context Protocol
---
# MCP Architecture Overview
## Component Relationships
```mermaid
graph TB
subgraph Client ["Client Layer"]
direction TB
C[MCP Client]
subgraph Handlers ["Client Handlers"]
direction LR
RH[Resource Handler]
TH[Tool Handler]
PH[Prompt Handler]
CH[Capability Handler]
end
TR[Transport Layer]
end
subgraph Server ["Server Layer"]
direction TB
S[MCP Server]
subgraph Managers ["Server Managers"]
direction LR
RM[Resource Manager]
TM[Tool Manager]
PM[Prompt Manager]
CM[Capability Manager]
end
SL[Storage Layer]
end
subgraph Integration ["Integration Layer"]
direction TB
IC[Integration Client]
IS[Integration Server]
subgraph Services ["Integration Services"]
direction LR
Cache[Resource Cache]
Stream[Resource Streamer]
Router[Request Router]
Monitor[Health Monitor]
end
end
C --> TR
TR --> S
C --> Handlers
RH --> Cache
RH --> Stream
TH --> Router
PH --> Router
S --> Managers
RM --> SL
TM --> SL
PM --> SL
IC --> IS
IS --> RM
IS --> TM
IS --> PM
style Client fill:#e1f3d8,stroke:#82c458
style Server fill:#ffd7d7,stroke:#ff8080
style Integration fill:#d7e3ff,stroke:#80b3ff
style Handlers fill:#f0f9eb,stroke:#82c458
style Managers fill:#ffe6e6,stroke:#ff8080
style Services fill:#e6f0ff,stroke:#80b3ff
```
## Capability Management Flow
```mermaid
sequenceDiagram
participant C as Client
participant CH as Capability Handler
participant T as Transport
participant CM as Capability Manager
participant S as Server
C->>CH: Initialize Capabilities
CH->>T: Connect with Capabilities
T->>CM: Negotiate Capabilities
CM->>S: Validate Capabilities
alt Valid Capabilities
S->>CM: Accept Capabilities
CM->>T: Send Accepted List
T->>CH: Update Active Capabilities
CH->>C: Ready with Capabilities
else Invalid Capabilities
S->>CM: Reject Capabilities
CM->>T: Send Rejection
T->>CH: Handle Rejection
CH->>C: Error: Incompatible
end
```
## Resource and Tool Flow
```mermaid
sequenceDiagram
participant C as Client
participant H as Handler
participant T as Transport
participant M as Manager
participant S as Storage
C->>+H: Request Operation
H->>Cache: Check Cache
alt Cache Hit
Cache-->>H: Return Cached
H-->>-C: Return Result
else Cache Miss
H->>+T: Forward Request
T->>+M: Process Request
M->>S: Access Storage
S-->>M: Return Data
M-->>-T: Send Response
T-->>-H: Return Result
H->>Cache: Update Cache
H-->>-C: Return Result
end
```
## Health Monitoring
```mermaid
stateDiagram-v2
[*] --> Monitoring
state Monitoring {
Healthy --> Degraded: Performance Issues
Degraded --> Unhealthy: Critical Issues
Unhealthy --> Degraded: Partial Recovery
Degraded --> Healthy: Full Recovery
state Healthy {
[*] --> Normal
Normal --> Warning: Minor Issues
Warning --> Normal: Auto-resolved
}
state Degraded {
[*] --> PartialService
PartialService --> Recovery: Auto-healing
Recovery --> [*]: Successful
}
}
Monitoring --> [*]: Shutdown
```
## Transport Flow
```mermaid
sequenceDiagram
participant C as Client
participant T as Transport
participant S as Server
participant H as Handlers
C->>T: Connect
T->>S: Establish Connection
S->>T: Connection Accepted
T->>C: Connected
C->>T: Request Resource
T->>S: Forward Request
S->>H: Process Request
H->>S: Return Result
S->>T: Send Response
T->>C: Deliver Response
```
## Resource Lifecycle
```mermaid
stateDiagram-v2
[*] --> Requested
Requested --> Fetching
Fetching --> Cached
Cached --> Streaming
Streaming --> Updated
Updated --> Cached
Cached --> Invalidated
Invalidated --> Fetching
Cached --> [*]
```
