Both are open source harness options with comparable terms, so the choice comes down to which model of the problem you prefer — compare the descriptions below rather than the licence.
Prime Intellect's recursive-language-model harness — a persistent IPython kernel is the only tool, sub-agents are function calls.
Drops fixed tool schemas and context compaction: the agent writes programs over its own context, and can CRUD its own prompts, skills and sub-agents mid-run.
Stateful agent server where memory is the primary abstraction.
| Prime Agent | Letta | |
|---|---|---|
| Licence | Open source | Open source |
| Pricing | open source | freemium |
| Self-hostable | Yes | Yes |
| Languages | Any language | Python, TypeScript |
| Install | curl -fsSL https://app.primeintellect.ai/prime-agent/install.sh | sh | pip install letta |
| Keys required | None | None |
Both are open source harness options with comparable terms, so the choice comes down to which model of the problem you prefer — compare the descriptions below rather than the licence. Prime Agent: Prime Intellect's recursive-language-model harness — a persistent IPython kernel is the only tool, sub-agents are function calls. Letta: Stateful agent server where memory is the primary abstraction.
Prime Agent can run on your own infrastructure. Letta can run on your own infrastructure.
Prime Agent is open source (open source). Letta is open source (freemium).
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/prime-agent-vs-letta