Find 18 Best AI Agent Observability with Agent Evaluation in November 2026

What is Langfuse?

Langfuse is an open-source LLM engineering platform for tracing, evaluation, prompt management, and metrics. It provides detailed traces of LLM application executions — capturing every LLM call, tool use, retrieval step, and agent action — and links traces to user sessions for production ...

What is LangSmith?

LangSmith is the LLMOps observability and evaluation platform built by LangChain for teams developing production LLM applications. It provides tracing, debugging, and evaluation for any LLM application — not just LangChain ones. Developers use LangSmith to trace every LLM call and tool ...

What is Laminar?

Laminar is an Apache 2.0 agent observability platform that records every run and then groups the failures it finds across all of them. Laminar Signals reads each run, extracts the task the agent was given, and reports the distribution of behaviours and failure modes rather than one trace at a ...

What is Pydantic Logfire?

Pydantic Logfire records agent runs as OpenTelemetry spans and keeps them beside the traces from the rest of the application, so an agent step and the database query it triggered sit in the same timeline. It reads instrumentation from 26 or more agent frameworks, and because the query language ...

What is Okareo?

Okareo tests voice, text and headless agents by driving simulated users at them and grading what the agent did. Voice agents are exercised the way a real call arrives, with a set of simulation drivers per run, and the trace and the transcript are shown together so a bad turn can be traced to ...

What is OpenLIT?

OpenLIT is an open-source platform for watching the whole harness an agent runs inside: the agent framework, the models it calls, the MCP servers it reaches, the vector databases it reads and the GPUs underneath. Everything is emitted as OpenTelemetry, so the same traces can be read in OpenLIT ...

What is Coval?

Coval puts a voice agent through simulated calls before real callers reach it, then keeps scoring the calls it takes in production. Agents built on Vapi, Retell, ElevenLabs and other platforms connect over SIP or an API, and the behaviours you care about are defined as metrics applied per call. ...

What is Judgment Labs?

Judgment is built for agents whose runs are long rather than short, where a single task can span hundreds of steps and the stored trace runs to a very large amount of text. Storage and indexing are shaped around that, so a billion tokens of agent data stay searchable. Background agents read the ...

What is Scorecard?

Scorecard runs an agent through large numbers of realistic scenarios and returns scores in minutes, so a prompt, model or logic change is judged on measured results rather than a few manual checks. Test sets are managed in the platform and prompts can be edited and compared in a playground, ...

What is AgentOps?

AgentOps records what an agent did on every run and lets an engineer rewind through it afterwards. Each model call, each action the agent took and each handoff between agents is captured as an event with its input, its output and its cost, so a run that went wrong can be opened and read back in ...

What is LangWatch?

LangWatch provides testing, evaluation and monitoring for LLM agents, with tracing across agent steps, automated evaluation including scenario-based agent testing, and prompt optimisation using DSPy. It is open-source with a self-hosted option and is framework-agnostic across common agent ...

What is Maxim AI?

Maxim AI covers the agent lifecycle from prompt experimentation through simulation and evaluation to production observability. Its simulation capability runs agents against generated user personas and scenarios to surface multi-turn failures that single-prompt evaluation misses — an agent can ...

What is HoneyHive?

HoneyHive provides observability and evaluation for production AI applications, combining distributed tracing across agent steps, online and offline evaluation, dataset curation from real traffic, and prompt management in one platform. Curating evaluation datasets directly from production ...

What is Opik?

Opik is Comet's open-source platform for tracing, evaluating and monitoring LLM applications, covering development-time experimentation and production monitoring in one tool. It records traces across chains and agents, supports LLM-as-judge and heuristic evaluators, and can gate CI on ...

What is Arize Phoenix?

Phoenix is Arize's open-source observability and evaluation tool for LLM applications, built on OpenTelemetry so traces are portable rather than locked to one vendor. It runs locally in a notebook or as a self-hosted service, capturing spans across retrieval, prompting and tool calls, and ...

What is Braintrust (AI Observability)?

Braintrust is an evaluation and observability platform for teams building production LLM applications and agents. It lets engineers log and trace LLM calls with latency, token, and cost metrics, run structured evals against datasets to score output quality, and replay logged production traces ...

What is Hamming AI?

Hamming enhances trust in AI voice agents by allowing customers to create and test thousands of adversarial voice agents. These voice agents can be tailored with various accents, objectives, and personalities to thoroughly evaluate the performance of the primary voice agents. For each call, ...

What is Arize AI?

Arize AI is a revolutionary Machine Learning Observability Platform to quickly identify and address model and data issues. With a comprehensive analytics suite and no restrictions on model framework, platform, or environment, Arize ensures companies can monitor the performance of their products ...