The Agent Stack: Evaluation & Testing

12 Companies 2 Categories The Agent Stack

Infrastructure used before production to test whether AI agents can complete intended tasks reliably. It covers simulated environments and functional evaluation. It excludes runtime security, policy enforcement, adversarial security testing, production control and audit evidence.

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Category

Simulated Environments & Test Worlds

4 companies

Products that give agents realistic but non-production systems to act inside. They reproduce software state and workflows so teams can test agent behavior without touching live systems. General compute sandboxes and security red-teaming tools are excluded.

Era

console.era.eon.io

Era is a simulated enterprise environment for developing and evaluating AI agents. It generates coherent synthetic companies across business systems and exposes them through vendor-compatible APIs and MCP servers.

Unknown Employees Unknown Stage 2026 Founded
Trajectory Maturity Level Nascent

Confidence: Medium

Arga Labs

argalabs.com

Arga Labs builds real world sandboxes that let teams test and train AI agents inside realistic replicas of external services before they touch production.

2 to 10 employees Employees Seed Stage 2025 Founded
Trajectory Maturity Level Emerging

Confidence: Medium

Waylabs

waylabs.org

Waylabs builds synthetic enterprise environments that let teams train and test AI agents inside realistic ghost companies instead of production systems.

unknown Employees Pre Seed Stage Unknown Founded
Trajectory Maturity Level Nascent

Confidence: Low

Plato

plato.so

Plato builds simulated workplaces that let AI labs train and evaluate agents on realistic job tasks without using live systems.

Not disclosed Employees Series A Stage 2025 Founded
Trajectory Maturity Level Nascent

Confidence: Medium

Category

Agent Evaluation & Regression Testing

8 companies

Products that measure whether an agent completes its intended tasks correctly and whether a new version improves or degrades performance. They focus on functional quality across full agent runs. Security testing and production monitoring are excluded.

Braintrust

braintrust.dev

Braintrust provides an agent observability and evaluation platform that helps teams test AI agents, catch regressions, and improve quality before release.

51-200 Employees Series B Stage 2023 Founded
Trajectory Maturity Level Proven

Confidence: Medium

LangChain

langchain.com

LangChain builds software for developing and testing AI agents, including LangSmith for evaluation, debugging, monitoring, and testing of LLM and agent workflows.

201-500 Employees Series B Stage 2023 Founded
Trajectory Maturity Level Established

Confidence: High

Confident AI

confident-ai.com

Confident AI is an AI quality platform for testing, evaluating, and improving AI applications and agents before and after deployment.

11-50 Employees Seed Stage 2023 Founded
Trajectory Maturity Level Emerging

Confidence: Medium

Latitude

latitude.so

Latitude is an open source platform for AI agent observability and evaluation. It traces agent runs, surfaces failures, and turns real production issues into evals that can catch regressions before users see them. ([latitude.so](https://latitude.so/?utm_source=openai))

2-10 Employees Seed Stage 2022 Founded
Trajectory Maturity Level Emerging

Confidence: Medium

Maxim AI

getmaxim.ai

Maxim AI builds an enterprise AI evaluation, observability, and gateway platform that helps teams route, govern, test, and monitor production AI applications.

11-50 Employees Seed Stage 2023 Founded
Trajectory Maturity Level Emerging

Confidence: High

Patronus AI

patronus.ai

Patronus AI builds evaluation and testing software that helps teams measure whether AI systems and agents work correctly and safely, then catch regressions before deployment.

51-200 Employees Series B Stage 2023 Founded
Trajectory Maturity Level Proven

Confidence: Medium

Langfuse

langfuse.com

Langfuse is an open source AI engineering platform that helps teams trace, evaluate, and improve LLM applications and AI agents in production.

16+ Employees Acquired Stage 2023 Founded
Acquired

Crux Labs

crux-labs.ai

Crux Labs turns expert judgment into custom evaluations that test AI agents on real tasks and track whether their performance changes.

Not disclosed Employees Unknown Stage Unknown Founded
Trajectory Maturity Level Early

Confidence: Medium

Investors

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Funding & Exits

Oct 2026

Plato

Series A

$16M • Investors: Nava Ventures, Gradient Ventures, Transpose Platform, Mustafa Suleyman

PR Newswire
Aug 2026
Jun 2026

Patronus AI

Series B

$50M • Investors: Greenfield Partners, Lightspeed Venture Partners, Notable Capital, Datadog, Samsung, Factorial Capital, Gokul Rajaram, others

Patronus AI raises $50 million Series B
Feb 2026
Jan 2026

Langfuse

Acquisition

Acquirer: ClickHouse • Status: Completed

Langfuse
Oct 2025

LangChain

Series B

$125M • Investors: IVP, Sequoia, Benchmark, Amplify, CapitalG, Sapphire Ventures

LangChain Series B
Mar 2025

Confident AI

Seed

$2.2M • Investors: Y Combinator, Flex Capital, Oliver Jung, Vermilion Cliffs Ventures, Liquid 2 Ventures, January Capital, Rebel Fund

Confident AI blog
Oct 2024

Braintrust

Series A

$36M • Investors: Andreessen Horowitz, Elad Gil, Greylock, Basecase, Datadog, Databricks Ventures, Guillermo Rauch, Simon Last, Bryan Helmig, Greg Brockman, Arthur Mensch

Announcing our $36 million Series A
Jun 2024

Maxim AI

Seed

$3M • Investors: Elevation Capital, Undisclosed angel investors from Postman, Undisclosed angel investors from Chargebee, Undisclosed angel investors from Groww, Undisclosed angel investors from Razorpay, Undisclosed angel investors from Media.net

Maxim AI official blog
May 2024

Patronus AI

Series A

$17M • Investors: Notable Capital, Lightspeed Venture Partners, Datadog, Gokul Rajaram, Factorial Capital, Jonathan Frankle, Jason Warner, Tristan Handy, Michael Callahan, Barr Moses, Aparna Sinha, Nadim Hossain, others

Announcing our $17M Series A
Feb 2024
Dec 2023
Nov 2023

Langfuse

Seed

$4M • Investors: Lightspeed Venture Partners, La Famiglia, Y Combinator

Langfuse
Sep 2023

Patronus AI

Seed

$3M • Investors: Lightspeed Venture Partners, Factorial Capital, Amjad Masad, Gokul Rajaram, Michael Callahan, Prasanna Gopalakrishnan, Suja Chandrasekaran, others

Patronus AI launches out of stealth
Apr 2023
Aug 2022
Undated

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Activity

Recently added to this landscape

Last updated

Plato builds simulated workplaces that let AI labs train and evaluate agents on realistic job tasks without using live systems.

Simulated Environments & Test Worlds

Crux Labs turns expert judgment into custom evaluations that test AI agents on real tasks and track whether their performance changes.

Agent Evaluation & Regression Testing