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Google Antigravity

Google's agentic development platform

Google Antigravity is an agentic development platform with four parts. The App is a command center for running multiple local agents in parallel. The CLI is terminal-first, with background subagents. The IDE is agentic, with an agent manager and artifacts. The Python SDK is for prototyping custom agents on the Antigravity harness.

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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
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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
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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

Sources

  1. Website