Pyke MCP Server
An MCP (Model Context Protocol) server for the Pyke logic programming inference engine. This server enables LLMs to perform logical reasoning through knowledge bases with facts, rules, and queries.
Features
- Fact Management: Add ground truth facts to the knowledge base
- Rule Definition: Define inference rules using forward chaining
- Query Execution: Check if facts can be derived from the knowledge base
- Goal Proving: Find all variable bindings that satisfy a goal
- Session Management: Support multiple independent knowledge bases
- Logic-LLM Compatible: Load programs in Logic-LLM format
Installation
Using pip
pip install git+https://github.com/evertrol/pyke3 pyke-mcp
From source
git clone https://github.com/NewJerseyStyle/pyke-mcp.git
cd pyke-mcp
pip install -e .
Dependencies
- Python 3.10+
mcp>=1.2.0pyke>=1.1.1(Install from source bypip install git+https://github.com/evertrol/pyke3but the package name ispykenotpyke3)
Quick Start
Running the Server
# Using the installed command
pyke-mcp
# Or using Python
python -m pyke_mcp.server
Configuration for Claude Desktop
Add to your claude_desktop_config.json:
macOS/Linux:
{
"mcpServers": {
"pyke": {
"command": "pyke-mcp"
}
}
}
Windows:
{
"mcpServers": {
"pyke": {
"command": "pyke-mcp"
}
}
}
Or with explicit Python path:
{
"mcpServers": {
"pyke": {
"command": "python",
"args": ["-m", "pyke_mcp.server"]
}
}
}
Available Tools
add_fact
Add a fact to the knowledge base.
Predicate(arg1, arg2, ...)
Examples:
Human(Socrates, True)- Socrates is humanParent(John, Mary)- John is a parent of Mary
add_rule
Add an inference rule using forward chaining.
Premise >>> Conclusion
Premise1 && Premise2 >>> Conclusion
Examples:
Human($x, True) >>> Mortal($x, True)- All humans are mortalParent($x, $y) && Parent($y, $z) >>> Grandparent($x, $z)- Grandparent relationship
add_facts_and_rules
Bulk add multiple facts and rules at once.
query
Check if a specific fact can be derived.
Predicate(Subject, ExpectedValue)
Example:
Mortal(Socrates, True)- "Is Socrates mortal?"
prove_goal
Find all variable bindings that satisfy a goal.
Examples:
Mortal($who, True)- "Who is mortal?"Parent($parent, Mary)- "Who are Mary's parents?"
get_program
Display the current knowledge base contents.
clear_program
Clear all facts and rules from the session.
load_logic_program
Load a complete logic program from formatted text (Logic-LLM compatible).
list_sessions
List all active sessions.
delete_session
Delete a specific session.
Usage Examples
Classic Syllogism
# Add facts
add_fact("Human(Socrates, True)")
add_fact("Human(Plato, True)")
# Add rule
add_rule("Human($x, True) >>> Mortal($x, True)")
# Query
query("Mortal(Socrates, True)")
# Result: True, Match: True
# Find all mortals
prove_goal("Mortal($who, True)")
# Bindings: who=Socrates, who=Plato
Family Relationships
# Facts
add_fact("Parent(Alice, Bob)")
add_fact("Parent(Bob, Charlie)")
add_fact("Parent(Bob, Diana)")
# Rules
add_rule("Parent($x, $y) && Parent($y, $z) >>> Grandparent($x, $z)")
# Find Alice's grandchildren
prove_goal("Grandparent(Alice, $grandchild)")
# Bindings: grandchild=Charlie, grandchild=Diana
Loading a Complete Program
program = """
Predicates:
Human(x, bool)
Mortal(x, bool)
Facts:
Human(Socrates, True)
Human(Aristotle, True)
Rules:
Human($x, True) >>> Mortal($x, True)
Query:
Mortal(Socrates, True)
"""
load_logic_program(program)
Logic Program Format
The server accepts programs in the Logic-LLM format:
Predicates:
PredicateName(arg1_type, arg2_type, ...)
Facts:
PredicateName(value1, value2, ...)
Rules:
Premise($var, value) >>> Conclusion($var, value)
Premise1($x, val) && Premise2($x, val) >>> Conclusion($x, val)
Query:
PredicateName(subject, expected_value)
Syntax Rules
-
Facts: Ground assertions without variables
Human(Socrates, True)Age(John, 30)
-
Rules: Implications with variables (prefixed with
$)Human($x, True) >>> Mortal($x, True)- Multiple premises joined with
&&
-
Variables: Prefixed with
$$x,$person,$value
-
Values: Can be boolean (
True/False) or stringsTrue,False,Socrates,Blue
Session Management
The server supports multiple independent sessions:
# Create/use a session
add_fact("Human(Socrates, True)", session_id="philosophy")
# Use a different session
add_fact("Cat(Whiskers, True)", session_id="animals")
# List sessions
list_sessions()
# Delete a session
delete_session("philosophy")
Error Handling
The server provides clear error messages for:
- Invalid fact/rule syntax
- Query execution failures
- Missing Pyke installation
- Session not found
Based On
- Pyke Knowledge Engine
- Logic-LLM - Pyke solver implementation
- clingo-mcp - MCP server interface reference
License
MIT License
