AgentEval: Free vs Paid — Is the Free Plan Enough?

⚡ Quick Verdict

Stay free if you only need full access to all core evaluation features and fluent assertions, stochastic evaluation, model comparison. Upgrade if you need optional add-ons on top of mit core and not yet available — in planning phase. Most solo builders can start free.

Try Free Plan →Compare Plans ↓

Who Should Stay Free vs Who Should Upgrade

👤

Stay Free If You're...

✓Individual user
✓Basic needs only
✓Personal projects
✓Getting started
✓Budget-conscious

👤

Upgrade If You're...

✓Business professional
✓Advanced features needed
✓Team collaboration
✓Higher usage limits
✓Premium support

What Users Say About AgentEval

👍 What Users Love

✓Native .NET integration with full type safety and compile-time error checking, unlike Python alternatives that rely on runtime exceptions
✓Red Team module ships with 192 attack probes across 9 attack types covering 60% of OWASP LLM Top 10 2025 with MITRE ATLAS technique mapping
✓Stochastic evaluation asserts on pass rates across N runs (e.g., 10 runs at 85% threshold) for statistically meaningful results
✓Trace record/replay eliminates API costs in CI — record once with real API, replay infinitely for free with identical outputs
✓Model comparison generates markdown leaderboards with cost/1K-request rankings across GPT-4o, GPT-4o Mini, Claude, and other providers
✓MIT licensed with explicit public commitment to remain open source forever — no bait-and-switch license changes
✓27 detailed samples included from Hello World through Multi-Agent Workflows and Cross-Framework evaluation
✓First-class Microsoft Agent Framework (MAF) integration with automatic tool call tracking and token/cost telemetry

👎 Common Concerns

⚠.NET-only — Python, JavaScript, and Go teams cannot use it and must rely on DeepEval, PromptFoo, or LangSmith instead
⚠Red Team coverage is 60% of OWASP LLM Top 10, leaving 40% of categories uncovered compared to specialized security scanners
⚠Commercial/Enterprise add-ons are still in planning phase, so enterprises requiring vendor SLAs and paid support have no tier to purchase
⚠Small community relative to Python-era evaluation tools means fewer third-party integrations, tutorials, and Stack Overflow answers
⚠Stochastic evaluation can become expensive — 100 tests × 50 repetitions equals 5,000 LLM calls per run if trace replay is not used
⚠Tight coupling to Microsoft Agent Framework concepts means evolving with Microsoft's roadmap rather than remaining provider-neutral

🔒 What Free Doesn't Include

🎯 Optional add-ons on top of MIT core

Why it matters: .NET-only — Python, JavaScript, and Go teams cannot use it and must rely on DeepEval, PromptFoo, or LangSmith instead

Available from: Commercial & Enterprise (Planned)

🎯 Not yet available — in planning phase

Why it matters: Red Team coverage is 60% of OWASP LLM Top 10, leaving 40% of categories uncovered compared to specialized security scanners

Available from: Commercial & Enterprise (Planned)

🎯 Core will remain MIT and fully usable without these

Why it matters: Commercial/Enterprise add-ons are still in planning phase, so enterprises requiring vendor SLAs and paid support have no tier to purchase

Available from: Commercial & Enterprise (Planned)

🎯 Details to be announced

Why it matters: Small community relative to Python-era evaluation tools means fewer third-party integrations, tutorials, and Stack Overflow answers

Available from: Commercial & Enterprise (Planned)

Frequently Asked Questions

Can I use AgentEval with Python agents?

No. AgentEval is built exclusively for .NET and ships on NuGet (nuget.org/packages/AgentEval). Python teams should use DeepEval, PromptFoo, or LangSmith for equivalent AI agent evaluation capabilities. Based on our analysis of 870+ AI tools, AgentEval is one of the only mature agent evaluation frameworks targeting the Microsoft/.NET ecosystem specifically, which is precisely its positioning.

Does AgentEval work with agents not built on Microsoft Agent Framework?

Yes. Any .NET agent that implements IChatClient can be tested via the IChatClient.AsEvaluableAgent() one-liner extension method. A Semantic Kernel bridge is also included for SK-based agents. This cross-framework design means you are not locked into MAF, though MAF is where the deepest integration exists with automatic tool call tracking and token/cost telemetry.

How does AgentEval compare to DeepEval and RAGAS?

DeepEval and RAGAS are Python frameworks with larger communities and broader metric catalogs. AgentEval is their .NET counterpart, offering equivalent coverage for RAG metrics (Faithfulness, Relevance, Context Precision/Recall), plus unique additions like the 192-probe Red Team module and fluent tool-chain assertions. Choose based on language ecosystem — AgentEval for C#/.NET shops, DeepEval/RAGAS for Python. All three are open source.

How much does stochastic testing cost in LLM API fees?

It scales with repetition count: 100 tests × 50 repetitions equals 5,000 LLM calls, roughly $15–$30 per test suite at GPT-4 pricing. AgentEval's recommended pattern is to use live stochastic evaluation only for new scenarios and switch to trace record/replay for regression testing in CI, which eliminates API costs entirely. The comparer's RunsPerModel option (typically 5) gives statistical stability without runaway cost.

What security vulnerabilities does the Red Team module detect?

The Red Team module runs 192 attack probes across 9 attack types: Prompt Injection, Jailbreaks, PII Leakage, System Prompt Extraction, Indirect Injection, Excessive Agency, Insecure Output Handling, API Abuse, and Encoding Evasion. This covers 6 of the OWASP LLM Top 10 2025 vulnerabilities (60% coverage) with MITRE ATLAS technique mapping, and results can be exported directly to PDF for compliance reporting via result.ExportAsync("security-report.pdf", ExportFormat.Pdf).

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