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Codebuff / Freebuff

The free coding agent, built on the open Codebuff multi-agent framework

Codebuff is a YC-backed terminal coding agent, installed with `npm install -g codebuff`. Its open repo now ships as Freebuff, built on Codebuff, which the README calls the open multi-agent framework behind its orchestration, tools and SDK (@codebuff/sdk). Specialized agents find files, implement, review, research docs and test in a browser, and can run in parallel in isolated workspaces.

Their open-source work

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The de-facto standard toolkit for building LLM applications and agents.

LangChain makes the LangChain framework and LangGraph, the low-level orchestration standard for stateful, controllable agents, plus the LangSmith platform for tracing, evaluating and monitoring them in production.

~$75M raised

4 pros · 4 cons
Featured

Devin, the AI software engineer, and the Windsurf IDE.

Cognition builds Devin, an autonomous AI software engineer that plans and executes engineering tasks end-to-end, and acquired the Windsurf agentic IDE in 2025. One of the defining startups of the coding-agent wave.

~$10.2B valuation (Sep 2025)

3 pros · 4 cons
Featured

Conversational AI agents for customer experience.

Sierra, co-founded by Bret Taylor and Clay Bavor, builds production conversational agents that resolve real customer issues with guardrails, evaluation and human escalation — a template for deploying vertical agents at the enterprise edge.

~$10B valuation (Oct 2025)

4 pros · 4 cons

Connections

Relations from the Harness Hub knowledge graph, as charted in the State of Harness reports.

Maintains · 1

Similar entries · 2

Sources

  1. Website
  2. GitHub