src/mcp/mcp_server_stdio.py

import sys
import os
sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

import spacy
import tiktoken
from lemminflect import getLemma
import re
from llm_optimizer import (
    optimize_with_llm, 
    optimize_with_agent, 
    get_accurate_token_count,
    PERSONAS
)
from fastmcp import FastMCP
from pydantic import Field

# ============================================================================
# spaCy Optimizer (kept separate as it's unique to this implementation)
# ============================================================================

class AdvancedPromptOptimizer:
    def __init__(self):
        self.nlp = spacy.load("en_core_web_sm")
        self.nlp.Defaults.stop_words -= {"not", "no", "never"}
        self.tokenizer = tiktoken.get_encoding("cl100k_base")
        self.negation_words = {"not", "no", "never", "without", "except"}

    def _mask_spans(self, s):
        masks = {}
        # triple backticks
        s, _ = re.subn(r"```.*?```", lambda m: masks.setdefault(f"<CODE{len(masks)}>", m.group(0)) or list(masks.keys())[-1], s, flags=re.S)
        # inline code
        s = re.sub(r"`[^`]+`", lambda m: masks.setdefault(f"<IC{len(masks)}>", m.group(0)) or list(masks.keys())[-1], s)
        # urls
        s = re.sub(r"https?://\S+", lambda m: masks.setdefault(f"<URL{len(masks)}>", m.group(0)) or list(masks.keys())[-1], s)
        # comparators
        s = re.sub(r"\b(less than|at least|no more than)\b", lambda m: masks.setdefault(f"<CMP{len(masks)}>", m.group(0)) or list(masks.keys())[-1], s, flags=re.I)
        return s, masks

    def _unmask_spans(self, s, masks):
        for k, v in masks.items():
            s = s.replace(k, v)
        return s

    def optimize(self, prompt: str, aggressiveness: float = 0.7) -> tuple:
        """Optimize prompt with token counting"""
        masked_prompt, masks = self._mask_spans(prompt)
        optimized = self._apply_rules(masked_prompt, aggressiveness)
        optimized = self._linguistic_optimize(optimized, aggressiveness)
        optimized = self._unmask_spans(optimized, masks)
        optimized = re.sub(r"\s+", " ", optimized).strip()

        try:
            orig_tokens = len(self.tokenizer.encode(prompt))
            new_tokens = len(self.tokenizer.encode(optimized))
        except:
            orig_tokens = len(prompt.split())
            new_tokens = len(optimized.split())

        return optimized, orig_tokens, new_tokens

    def _apply_rules(self, text: str, aggressiveness: float) -> str:
        rules = [
            (r"\s{2,}", " ", 0.0),
            (r"\b(\w+)\s+\1\b", r"\1", 0.0),
            (r"\b(advantages and disadvantages)\b", "pros/cons", 0.5),
            (r"\b(in a detailed manner|in a detailed way)\b", "", 0.7),
            (r"\b(I want to|I need to|I would like to)\b", "", 0.7),
            (r"\b(for example|e\.g\.|such as|i\.e\.)\b", "e.g.", 0.8),
            (r"\b(please\s+)?(kindly\s+)?(carefully|very|extremely|really|quite)\b", "", 0.8),
            (r"\b(can you|could you|would you)\b", "", 0.9),
            (r"\b(output|provide|give|return)\s+in\s+(JSON|json)\s+format\b", "JSON:", 1.0),
        ]
        for pattern, repl, priority in rules:
            if aggressiveness >= priority:
                text = re.sub(pattern, repl, text, flags=re.IGNORECASE)
        return text

    def _linguistic_optimize(self, text: str, aggressiveness: float) -> str:
        if not text.strip():
            return text
        doc = self.nlp(text)
        out = []
        for token in doc:
            if token.text.lower() in ["deliverables:", "constraints:", "metrics:"] and token.is_sent_start:
                out.append(token.text)
                continue

            if token.pos_ in ("PUNCT", "SPACE"): continue
            if token.like_num or token.ent_type_ or token.dep_ == "neg" or token.text.lower() in self.negation_words:
                out.append(token.text)
                continue
            if token.pos_ in ("PROPN", "NUM", "NOUN", "ADJ"):
                out.append(token.text)
                continue
            if token.pos_ == "VERB":
                if aggressiveness >= 0.8:
                    lemma = getLemma(token.text, upos="VERB") or [token.lemma_]
                    out.append(lemma[0])
                else:
                    out.append(token.text)
                continue
            if token.pos_ in ("ADV", "DET", "PRON"):
                if aggressiveness < 0.6:
                    out.append(token.text)
                continue
            out.append(token.text)
        return " ".join(out)

# ============================================================================
# FastMCP Server
# ============================================================================

mcp = FastMCP("PromptOptimizer")

@mcp.tool
def optimize_prompt(
    prompt: str = Field(description="The prompt to optimize"),
    method: str = Field(default="simple", description="The optimization method to use. Can be 'simple', 'agent', or 'spacy'"),
    persona: str = Field(default="Default", description="The persona to use for LLM-based optimization"),
    aggressiveness: float = Field(default=0.7, description="The aggressiveness level for spaCy-based optimization"),
) -> str:
    """Optimizes a given prompt using various methods to reduce token count while preserving meaning."""
    # Get API keys from environment variables (passed by MCP client)
    aimlapi_key = os.getenv("AIMLAPI_API_KEY")
    tavily_key = os.getenv("TAVILY_API_KEY")
    
    if method == "simple":
        if not aimlapi_key:
            return "Error: AIMLAPI_API_KEY environment variable is required for simple optimization"
        result = optimize_with_llm(prompt, aimlapi_key, persona)
        return result
    elif method == "agent":
        if not aimlapi_key or not tavily_key:
            return "Error: Both AIMLAPI_API_KEY and TAVILY_API_KEY environment variables are required for agent-based optimization"
        result = optimize_with_agent(prompt, aimlapi_key, persona, tavily_key)
        return result
    elif method == "spacy":
        optimizer = AdvancedPromptOptimizer()
        optimized, orig_tokens, new_tokens = optimizer.optimize(prompt, aggressiveness)
        result = f"Original tokens: {orig_tokens}\nOptimized tokens: {new_tokens}\nSavings: {orig_tokens - new_tokens} tokens\n\nOptimized prompt:\n{optimized}"
        return result
    else:
        return "Error: Invalid method. Use 'simple', 'agent', or 'spacy'"

@mcp.tool
def get_available_personas() -> str:
    """Get list of available optimization personas and their descriptions."""
    return "\n".join([f"- {persona}: {desc.split('.')[0]}..." for persona, desc in PERSONAS.items()])

@mcp.tool
def count_tokens(
    text: str = Field(description="The text to count tokens for"),
    model: str = Field(default="gpt-4", description="The model to use for tokenization"),
) -> str:
    """Count tokens in text using specified model tokenizer."""
    count = get_accurate_token_count(text, model)
    return f"Token count: {count}"

@mcp.resource("config://optimization-methods")
def list_optimization_methods() -> list[str]:
    """List available optimization methods."""
    return ["simple", "agent", "spacy"]

@mcp.resource("config://personas")
def list_personas() -> list[str]:
    """List available personas for optimization."""
    return list(PERSONAS.keys())

@mcp.resource("config://persona/{persona_id}")
def fetch_persona_details(persona_id: str) -> str:
    """Get details for a specific persona."""
    if persona_id not in PERSONAS:
        raise ValueError(f"Persona with id {persona_id} not found")
    return PERSONAS[persona_id]

@mcp.prompt
def optimize_for_persona(
    text: str = Field(description="Text to optimize"),
    persona: str = Field(description="Persona to optimize for"),
) -> str:
    """Creates an optimization prompt tailored to a specific persona."""
    if persona not in PERSONAS:
        persona = "Default"
    
    return f"""
Your goal is to optimize the following text for the {persona} persona.

The text to optimize is:
<text>
{text}
</text>

Persona guidelines:
{PERSONAS[persona]}

Use the 'optimize_prompt' tool with method='simple' to optimize the text.
After optimization, respond with the optimized version and explain what changes were made.
"""

if __name__ == "__main__":
    # Run with stdio transport (default for FastMCP)
    mcp.run()