OpenAI Agents SDK vs Claude Agent SDK
OpenAI Agents SDK vs Claude Agent SDK: which official agent framework wins for your use case. Composable lightweight primitives vs computer-use environment primitives. Both work with self-hosted fine-tuned models.
Overview
_Updated 2026-05-10 — reflects OpenAI Agents SDK v0.17.0 (May 7) bumping the default RealtimeAgent model to `gpt-realtime-2`, and the May 8 Claude Agent SDK release adding a `defer` permission decision in PreToolUse hooks, a `strict` MCP option, batched/eager `session_store_flush` for live transcript tailing, and an `xhigh` effort level._
By 2026, both OpenAI and Anthropic have released official agent SDKs, and both have made deliberate choices about what their frameworks include. OpenAI's Agents SDK is intentionally minimal — a few core primitives (Agent, Tool, Handoff, Runner) that compose into arbitrarily complex workflows without the conceptual overhead of older frameworks. Claude's Agent SDK takes the opposite approach, including production-grade implementations of common environment primitives (computer-use, sandboxed code execution, file system access, web search) so the agent can take action in computer environments without each team building those layers from scratch.
Both SDKs are model-agnostic at the orchestration layer — neither locks you into the framework author's hosted models. The OpenAI Agents SDK accepts any OpenAI-compatible HTTP endpoint, which means Ollama, vLLM, LM Studio Server, and other self-hosted runtimes all work. The Claude Agent SDK provides a model-provider abstraction that supports the same range of backends. The choice between them is therefore not about API economics — both can run against fine-tuned local models — but about which framework's shape matches your problem.
This comparison helps you pick the right SDK based on your agent's environment requirements, then explains how an Ertas-trained model improves reliability under either framework.
Feature Comparison
| Feature | OpenAI Agents SDK | Claude Agent SDK |
|---|---|---|
| Released by | OpenAI | Anthropic |
| Released | 2024 (Swarm successor) | 2024–2025 |
| Languages | Python + TypeScript (@openai/agents) | Python (TS in development) |
| Design philosophy | Minimal composable primitives | Environment-rich primitives |
| Built-in computer-use | ||
| Built-in code execution sandbox | ||
| Built-in file system primitive | ||
| Built-in web search | ||
| Multi-agent handoffs | First-class | Manual composition |
| Tracing built in | ||
| Model-agnostic | ||
| Works with fine-tuned local models | ||
| License | MIT | MIT |
Strengths
OpenAI Agents SDK
- Lightweight, composable design — minimal conceptual overhead
- First-class TypeScript companion (@openai/agents) for JavaScript projects and mobile-app backends
- Multi-agent handoffs as a first-class primitive — easier than rolling your own coordination
- Built-in tracing system that works regardless of underlying model
- Designed deliberately to be model-agnostic — point at any endpoint and the SDK works
- Best developer experience among the official agent SDKs as of 2026
- Smaller surface area means fewer bugs and easier debugging
Claude Agent SDK
- Production-grade environment primitives — computer-use, code execution, file system, web search
- 'Give the agent a computer' design philosophy — agents reason at higher level, not micro-actions
- Sandboxed execution by default — built-in security primitives for risky operations
- Particularly strong for computer-use agents (Operator-style workflows)
- Built-in safety primitives — action permissions, audit trails, sandboxing
- Less work to ship environment-rich agents — battle-tested implementations rather than build-your-own
- Strong fit for internal-ops automation, screen-reading assistants, code-execution agents
Which Should You Choose?
OpenAI Agents SDK is the lighter-weight choice for agents that don't need a computer environment. Faster to ship, smaller code surface, easier to debug.
Claude Agent SDK's computer-use primitive is production-grade and battle-tested. Building this from scratch on top of the OpenAI Agents SDK is meaningful work.
Claude Agent SDK's sandboxed code execution primitive includes the safety filtering and resource limits that production code-running agents need.
OpenAI Agents SDK's TypeScript companion (@openai/agents) is a first-class peer to the Python version. Claude Agent SDK's TypeScript story is less mature in 2026.
OpenAI Agents SDK treats handoffs as a first-class primitive. Claude Agent SDK supports multi-agent through composition but doesn't have the same dedicated abstraction.
Claude Agent SDK's environment primitives (file system, code execution, computer-use) plus its sandboxing make it the natural fit. The framework gives you the operational guarantees you need.
Claude Agent SDK's web-search primitive plus the sandboxed code execution for synthesis matches this use case directly. OpenAI Agents SDK would require integrating these from scratch.
OpenAI Agents SDK's lightweight design and TypeScript companion fit the mobile-backend pattern naturally. Claude Agent SDK's computer-use primitives are unused weight for on-device agents.
Verdict
Pick OpenAI Agents SDK when your agent's actions are mostly tool calls — CRM lookups, API requests, structured outputs, multi-agent handoffs. The framework's minimal primitive set keeps the code surface small and the latency low, and the TypeScript companion makes it the right pick for mobile-app backends. Pick Claude Agent SDK when your agent needs to take action in a computer environment — browser automation, code execution, file system manipulation, web search. The framework's environment primitives are battle-tested and would be significant work to build yourself.
Neither framework requires you to use the developer's hosted model. Both accept self-hosted endpoints, which makes the API-economics question independent of the framework choice. For teams whose primary concern is per-token cost rather than environment-primitive complexity, both frameworks become equally attractive after the model is swapped to a fine-tuned local one.
How Ertas Fits In
Both SDKs work cleanly with fine-tuned models served via Ollama, vLLM, or Ertas Cloud. The OpenAI Agents SDK's `OpenAIChatCompletionsModel` configures with a base URL and a model name; the Claude Agent SDK's OpenAI-compatible provider does the same. Once configured, every agent — whether it's calling tools, executing code, or coordinating handoffs — runs against your fine-tuned model.
The combination is particularly relevant for the agentic cost cliff. Agents make many model calls per task (5–30, depending on workflow), so the per-token bill scales with the loop, not with user-facing turns. An app at 1K MAU paying $120/month on baseline cloud APIs is typically paying $3,000+/month at 40K MAU. Swapping the underlying model to an Ertas-trained local one — without changing the SDK code — flips the curve from variable to fixed. For mobile app builders shipping AI features, this is the difference between staying on the cliff and getting off it. The Ertas Deployment CLI bridges from the GGUF export to a working iOS, Android, Flutter, or React Native integration in minutes.
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