The foundation for
context-aware AI

Create and compare prompts, tools, and models.

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Powering applications built with

OpenAI
Anthropic
Google
Meta
Mistral
Cohere

Craft prompts that generate outcomes

Stop guessing. Start building with data-driven prompt engineering.

Real-time iteration

Chat with AI to refine your prompts instantly. See results as you type, test edge cases, and perfect your instructions.

Version control built-in

Track every change with automatic versioning. Compare performance across iterations and never lose a good prompt.

Test across models

Run evaluations on GPT-4, Claude, Gemini, and more. Find the perfect model for your use case with side-by-side comparisons.

Share and collaborate

Export prompts and tools to share with your team. Create public links to showcase your best work to the community.

Prompt Optimization
Before (Traditional) -156
Let's think step by step about this problem. First, we need to identify the key components. Then, we should analyze each part carefully...
After (Optimized) +42
Solve this optimization problem: [problem]
Requirements: Show mathematical steps, verify solution, explain assumptions.
+20% accuracy
3 tools active
Testing with GPT-4o, Sonnet 3.5 2 min ago
"Adding just three high-level instructions increased our internal SWE-bench Verified score by ≈ 20 percentage points."
OpenAI — OpenAI Engineering Team

Small prompt improvements create massive performance gains. PromptSlice helps you find and validate those improvements with data, not guesswork.

Define tools with AI assistance

Create and refine tool definitions alongside your prompts. Let AI help you craft optimal function schemas based on best practices.

"Optimised tool definitions cut required tool calls by up to 70% and eliminated 47% redundancies."

— Wu et al., Findings of ACL 2025

AI-powered tool creation

Chat with AI to generate optimal tool definitions. Get suggestions for parameter schemas, descriptions, and validation rules.

Version and test together

Tools are versioned just like prompts. Test different combinations of prompt and tool versions to find what works best.

Optimize with data

Monitor success rates and performance metrics. Refine definitions based on evaluation results and real-world testing.

Import and export

Import OpenAPI specs, export to standard formats. Share tool definitions with your team or the community.

Tool Builder
{
"name": "get_weather",
"description": "Get current weather for a location",
"parameters": {
"location": {
"type": "string",
"description": "City and state/country"
},
"units": {
"type": "string",
"enum": ["celsius", "fahrenheit"]
}
},
"required": ["location"]
}
Validated schema
AI optimized
Tested with GPT-4.1, Sonnet 4, Gemini 2.5 Pro 5 min ago

Test on every model

One prompt, infinite possibilities. Find the perfect model-prompt combination for your use case.

OpenAI GPT-4o
Accuracy 94%
Speed 1.2s
Cost $0.03
Anthropic Claude 3.5
Accuracy 96%
Speed 0.9s
Cost $0.02
Gemini Gemini Pro
Accuracy 89%
Speed 0.7s
Cost $0.01
Llama Llama 3
Accuracy 87%
Speed 0.5s
Cost $0.00
Best overall Based on 1,247 tests
Anthropic Claude 3.5 Sonnet
96% accuracy

Compare everything that matters

Run your prompts across all major models simultaneously. Track accuracy, latency, cost, and consistency to make data-driven decisions.

  • Test GPT-4, Claude, Gemini, Llama, Mistral, and more
  • Automated evaluation suites with custom metrics
  • Real-time cost tracking and optimization
  • Export results for deeper analysis

Deploy with confidence

Know exactly which model performs best for your specific use case before going to production.

Ready to build better prompts?

Join teams using PromptSlice to ship AI features with confidence.

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