Pyke MCP Server

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>=1.2.0
• pyke>=1.1.1 (Install from source by pip install git+https://github.com/evertrol/pyke3 but the package name is pyke not pyke3)

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 human
• Parent(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 mortal
• Parent($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

1. Facts: Ground assertions without variables

   • Human(Socrates, True)
   • Age(John, 30)

2. Rules: Implications with variables (prefixed with $)

   • Human($x, True) >>> Mortal($x, True)
   • Multiple premises joined with &&

3. Variables: Prefixed with $

   • $x, $person, $value

4. Values: Can be boolean (True/False) or strings

   • True, 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 Handl