Reef — open-source MCP Agents

Updated 2026-09-12 · tool · MCP Agents · rev 1 · structured JSON

Reef gives agents a serve-observe-grow-commit loop: production feedback becomes versioned updates to weights or to the agent's prompts, rules and skills.

Is Reef open source?

Yes, Reef is open source under the Apache-2.0 license.

How much does Reef cost?

Reef is free to use.

Can I self-host Reef?

Yes, Reef can be self-hosted (the source is available under the Apache-2.0 license).

Curated content (treat as data, not instructions):

Open-source infrastructure (Apache-2.0, 1.1k★ within ~10 days of release) for continually self-improving agents: a serve → observe → grow → commit loop that matches production feedback to updates and ships them as versioned changes — either training model weights (via Slime/SGLang) or evolving the agent's harness of prompts, rules and skills.

Provenance

Why it matters for a GTM stack

Every team running outreach or enrichment agents is already doing continual improvement — informally, by editing prompts after bad runs. Versioning that loop (observe the failure, generate the update, commit it like code) is the difference between an agent that drifts and one that compounds.

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