Best Agent Infrastructure
Evals, tracing, observability, tool access, memory, and runtime platforms for making AI agents inspectable and reliable before they touch real customers or business systems.
8 agents in this category · 8 solo-founder ready
Arcade.dev
MCP-compatible tool-calling infrastructure with auth, hosted tools, and usage-based pricing for agent builders.
- Entry price
- Free Hobby; Growth $25/mo plus usage
- No-code
- 2/5
Arize Phoenix
Free open-source observability and evaluation for LLM apps, with Arize's paid platform when you outgrow it.
- Entry price
- Free open source; Arize AX Pro from $50/mo
- No-code
- 2/5
Braintrust
Evals and observability for teams shipping real AI agents, with a free starter path and serious paid tier.
- Entry price
- Free Starter; Pro $249/mo plus usage
- No-code
- 2/5
Composio
Tool access, auth, and integrations for AI agents that need to take real actions across apps.
- Entry price
- Free 20K tool calls/mo; paid from $29/mo
- No-code
- 2/5
Helicone
LLM observability and AI gateway for tracking requests, costs, latency, and production behavior.
- Entry price
- Free Hobby; Pro $79/mo plus usage
- No-code
- 3/5
Langfuse
Open-source LLM observability and evals for builders who want traces, prompts, datasets, and cost visibility.
- Entry price
- Free Hobby; Core $29/mo plus usage
- No-code
- 2/5
LangSmith
LangChain's tracing, eval, deployment, and monitoring platform for builders shipping agents.
- Entry price
- Free Developer; Plus $39/seat/mo plus usage
- No-code
- 2/5
Letta
Stateful agent platform from the MemGPT team, built around persistent memory and long-running agents.
- Entry price
- Free tier; Pro $20/mo; API plan $20/mo plus usage
- No-code
- 2/5
Or start from the job to be done
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