Memory MCP Server
A Model Context Protocol (MCP) server that provides knowledge graph functionality for managing entities, relations, and observations in memory, with strict validation rules to maintain data consistency.
Installation
Install the server in Claude Desktop:
Data Validation Rules
Entity Names
- Must start with a lowercase letter
- Can contain lowercase letters, numbers, and hyphens
- Maximum length of 100 characters
- Must be unique within the graph
- Example valid names:
python-project,meeting-notes-2024,user-john
Entity Types
The following entity types are supported:
person: Human entities
concept: Abstract ideas or principles
project: Work initiatives or tasks
document: Any form of documentation
tool: Software tools or utilities
organization: Companies or groups
location: Physical or virtual places
event: Time-bound occurrences
Observations
- Non-empty strings
- Maximum length of 500 characters
- Must be unique per entity
- Should be factual and objective statements
- Include timestamp when relevant
Relations
The following relation types are supported:
knows: Person to person connection
contains: Parent/child relationship
uses: Entity utilizing another entity
created: Authorship/creation relationship
belongs-to: Membership/ownership
depends-on: Dependency relationship
related-to: Generic relationship
Additional relation rules:
- Both source and target entities must exist
- Self-referential relations not allowed
- No circular dependencies allowed
- Must use predefined relation types
Usage
The server provides tools for managing a knowledge graph:
Get Entity
Get Graph
Create Entities
Add Observation
Create Relation
Search Memory
The search functionality supports:
- Temporal queries (e.g., "most recent", "last", "latest")
- Activity queries (e.g., "workout", "exercise")
- General entity searches
- Fuzzy matching with 80% similarity threshold
- Weighted search across:
Delete Entities
Delete Relation
Flush Memory
Error Types
The server uses the following error types:
NOT_FOUND: Entity or resource not found
VALIDATION_ERROR: Invalid input data
INTERNAL_ERROR: Server-side error
ALREADY_EXISTS: Resource already exists
INVALID_RELATION: Invalid relation between entities
Response Models
All tools return typed responses using these models:
EntityResponse
GraphResponse
OperationResponse
Development
Running Tests
Adding New Features
- Update validation rules in
validation.py
- Add tests in
tests/test_validation.py
- Implement changes in
knowledge_graph_manager.py
Memory MCP Server
A Model Context Protocol (MCP) server that provides knowledge graph functionality for managing entities, relations, and observations in memory, with strict validation rules to maintain data consistency.
Installation
Install the server in Claude Desktop:
Data Validation Rules
Entity Names
- Must start with a lowercase letter
- Can contain lowercase letters, numbers, and hyphens
- Maximum length of 100 characters
- Must be unique within the graph
- Example valid names:
python-project,meeting-notes-2024,user-john
Entity Types
The following entity types are supported:
person: Human entities
concept: Abstract ideas or principles
project: Work initiatives or tasks
document: Any form of documentation
tool: Software tools or utilities
organization: Companies or groups
location: Physical or virtual places
event: Time-bound occurrences
Observations
- Non-empty strings
- Maximum length of 500 characters
- Must be unique per entity
- Should be factual and objective statements
- Include timestamp when relevant
Relations
The following relation types are supported:
knows: Person to person connection
contains: Parent/child relationship
uses: Entity utilizing another entity
created: Authorship/creation relationship
belongs-to: Membership/ownership
depends-on: Dependency relationship
related-to: Generic relationship
Additional relation rules:
- Both source and target entities must exist
- Self-referential relations not allowed
- No circular dependencies allowed
- Must use predefined relation types
Usage
The server provides tools for managing a knowledge graph:
Get Entity
Get Graph
Create Entities
Add Observation
Create Relation
Search Memory
The search functionality supports:
- Temporal queries (e.g., "most recent", "last", "latest")
- Activity queries (e.g., "workout", "exercise")
- General entity searches
- Fuzzy matching with 80% similarity threshold
- Weighted search across:
Delete Entities
Delete Relation
Flush Memory
Error Types
The server uses the following error types:
NOT_FOUND: Entity or resource not found
VALIDATION_ERROR: Invalid input data
INTERNAL_ERROR: Server-side error
ALREADY_EXISTS: Resource already exists
INVALID_RELATION: Invalid relation between entities
Response Models
All tools return typed responses using these models:
EntityResponse
GraphResponse
OperationResponse
Development
Running Tests
Adding New Features
- Update validation rules in
validation.py
- Add tests in
tests/test_validation.py
- Implement changes in
knowledge_graph_manager.py