Perplexity AI Search (Safe Edition)

Overview

This skill provides access to the Perplexity API for web-grounded AI search. It combines large language models with real-time web search, providing accurate, up-to-date answers with source citations.

This is a security-hardened version that fixes command injection vulnerabilities found in the original perplexity-bash skill.

When to Use Perplexity vs. Built-in Search

Use Perplexity when:

• You need current information (news, prices, events, recent developments)
• The user asks for source citations or references
• The user specifically mentions Perplexity or wants research-style answers

Use built-in web search when:

• Simple factual queries
• Quick information lookup
• Basic URL or content retrieval

Model Selection Guide

Quick Start

Basic Search

# Simple query (uses sonar by default)
scripts/perplexity_search.sh "What is the capital of Germany?"

# With a different model
scripts/perplexity_search.sh -m sonar-pro "Latest AI developments"

# Markdown format with citations
scripts/perplexity_search.sh -f markdown "Tesla stock analysis"

Advanced Usage

# High context for comprehensive results
scripts/perplexity_search.sh -m sonar-reasoning -c high -f markdown \
  "Compare AI models performance benchmarks"

# With custom system prompt
scripts/perplexity_search.sh -s "You are a technology analyst." \
  "Analyze current tech trends"

Options

Search Context Size

• low - Faster, fewer sources. Good for simple queries.
• medium (default) - Balanced for most use cases.
• high - Most comprehensive. Best for research.

Setup Requirements

API Key Configuration

Option 1: Config file (recommended)

Create config.json in the skill directory:

{
  "apiKey": "pplx-your-key-here"
}

Option 2: Environment variable

export PERPLEXITY_API_KEY="your-key-here"

Priority: Config file > environment variable.

Dependencies

• bash (4.0+)
• curl
• python3 (for JSON construction only - no user input is eval'd)

Security Notes

This version addresses the following vulnerabilities found in the original:

1. No command injection - User input is passed to Python via environment variables, never interpolated into code strings
2. Input validation - All parameters are validated (numeric ranges, allowed model names, allowed context values)
3. API key protection - The Authorization header is passed to curl via a temporary config file (curl -K, mode 600) and the request body via stdin (--data @-), so neither the API key nor the body appear in process listings (ps aux)
4. Query length limit - Queries are capped at 8000 characters to prevent denial-of-wallet attacks
5. Strict model allowlist - Only known valid models are accepted

Cost Awareness

Perplexity API is not free. Be mindful of usage:

• Simple queries: ~$0.005-$0.015 per query
• Deep research: ~$0.015-$0.03+ per query
• Default to sonar for most queries to keep costs low.

Troubleshooting

• Error: No API key found - Set up API key as described above
• Error: curl not found - Install curl for your system
• Error: Invalid model - Use --list-models to see available models