The deciding difference is operational: Hermes Agent can run on infrastructure you control, Claude Agent SDK cannot. If that constraint is real for you, it settles the choice before anything else is considered.
The Claude Code loop as a library, for agents that are not about code.
Same harness as Claude Code, but you own the entrypoint and the tool surface.
Self-improving agent from Nous Research — writes its own skills from experience and carries them forward.
The learning loop is the point: it creates skills after complex tasks and searches its own past sessions. Runs anywhere from a $5 VPS to Modal or Vercel Sandbox.
| Claude Agent SDK | Hermes Agent | |
|---|---|---|
| Licence | Proprietary | Open source |
| Pricing | usage based | open source |
| Self-hostable | No | Yes |
| Languages | TypeScript, Python | Any language |
| Install | npm install @anthropic-ai/claude-agent-sdk | curl -fsSL https://hermes-agent.nousresearch.com/install.sh | bash |
| Keys required | ANTHROPIC_API_KEY | None |
The deciding difference is operational: Hermes Agent can run on infrastructure you control, Claude Agent SDK cannot. If that constraint is real for you, it settles the choice before anything else is considered. Claude Agent SDK: The Claude Code loop as a library, for agents that are not about code. Hermes Agent: Self-improving agent from Nous Research — writes its own skills from experience and carries them forward.
Claude Agent SDK is a hosted service only. Hermes Agent can run on your own infrastructure.
Claude Agent SDK is proprietary (usage based). Hermes Agent is open source (open source).
Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.
curl -s -H "Accept: text/markdown" https://newagent.build/compare/claude-agent-sdk-vs-hermes-agent