HaystackFreemium
An open-source framework from deepset for building production LLM applications — RAG, search, and agents — built around composable pipelines.
Agent Development comparison
Haystack vs OpenAI AgentKit
Pricing, pros, cons, and ideal use cases — side by side.
OpenAI AgentKitFreemium
OpenAI first-party agent toolkit — a visual Agent Builder, embeddable ChatKit UI, a connector registry, and evals, billed at plain API rates.
At a glance
| Haystack | OpenAI AgentKit | |
|---|---|---|
| Pricing | FreemiumOpen-source framework is free. The deepset AI Platform is a paid, enterprise-oriented managed offering. | FreemiumNo separate platform fee. Agent Builder design is free; you pay standard OpenAI API model and storage rates for execution. As a reference point, GPT-5.2 runs roughly $1.75 per million input tokens and $14 per million output tokens, with GPT-5 mini at about $0.25 per million input tokens. |
| Category | Agent Development | Agent Development |
| Ideal for | Teams building production RAG and searchEngineering orgs that want inspectable pipelinesEnterprises evaluating managed LLM platforms | Product teams embedding agents into their own softwareEngineering teams already building on the OpenAI APIStartups that want agent scaffolding without a platform feeTeams standardizing evals alongside agent development |
Pros & cons
Haystack
Pros
- Explicit, testable pipeline architecture
- Mature retrieval and evaluation tooling
- Managed deepset platform for governed deployments
- Production-focused rather than demo-focused
Cons
- Pipeline model is less flexible than free-form agents
- Smaller community than LangChain or LlamaIndex
- Managed platform pricing requires a sales conversation
OpenAI AgentKit
Pros
- No platform fee on top of API usage
- Visual workflow builder with versioning
- ChatKit ships a production-ready chat UI
- Evals are first-class rather than an afterthought
- Cost model is the API cost model you already forecast
Cons
- Single-provider lock-in at the orchestration layer
- Agent Builder and Connector Registry have been in beta rather than fully GA
- Fewer enterprise governance controls than Copilot Studio or Agentforce
- No managed hosting story comparable to Bedrock AgentCore
Which should you choose?
Haystack is built around teams building production rag and search; OpenAI AgentKit leans more toward product teams embedding agents into their own software. Shortlist the one whose strengths line up with your biggest constraint.
Still deciding between Haystack and OpenAI AgentKit?
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