# AI Apps That Work free tools

> These figures are automated measurements with timestamps. They are not a review, rating, grade, or recommendation.

Real cost per AI result, LLM prices, switch costs, shutdown dates, A/B test sizes and judge checks.

- Status: Up
- Checks passed: 13 of 22
- Uptime: Not measured
- Latency: 448 ms
- Tools: 8
- Last probe: 2026-11-12T13:03:07.395Z
- Publisher: aiappsthatwork.com (https://mcpheartbeat.com/p/com.aiappsthatwork)
- Endpoint: https://aiappsthatwork.com/mcp
- Transport: streamable-http

## Tools

Showing 8.

- **ab_test_sample_size**: Returns how many results each version of a prompt or model needs before a difference in how often results work first time is statistically real (two-proportion
- **build_judge_prompt**: Builds a pass/fail LLM-as-a-judge prompt for one kind of AI step (make, answer, transform, extract, judge, find, predict, plan, act or learn). Returns the promp
- **judge_agreement**: Compares a person's verdicts with an AI judge's verdicts on the same results. Returns the agreement rate, Cohen's kappa with confidence intervals, precision and
- **launch_checklist**: The 20 AI-specific launch checks for an AI app (spending caps, rate limits, server-side keys, credit charging, version tags, records of which results worked fir
- **model_prices**: Looks up list prices for LLMs (USD per million input, output and cached input tokens, and context size), image models (USD per image by quality and size) and vi
- **model_shutdowns**: Lists announced API shutdown dates for AI models from OpenAI, Anthropic, Google and other providers, with days left, the suggested replacement, the source page,
- **model_switch_cost**: Compares two priced LLMs on six common task shapes (support answer, invoice extraction, lead scoring, email draft, translation, search re-ranking). Returns list
- **real_cost_per_result**: Prices the AI steps behind one request from current list prices (LLM tokens, images, video seconds or a fixed amount) and returns the cost per request, the real

## Recent probes

- 2026-11-12T13:03:07.395Z: Connected, 448 ms, 8 tools

## Links

- HTML: https://mcpheartbeat.com/s/com.aiappsthatwork/tools/status
- Markdown: https://mcpheartbeat.com/s/com.aiappsthatwork/tools/status.md
- MCP: https://mcpheartbeat.com/mcp
- API: https://mcpheartbeat.com/api/v1/servers
- Tools API: https://mcpheartbeat.com/api/v1/tools
- Server API: https://mcpheartbeat.com/api/v1/health?server=com.aiappsthatwork%2Ftools