Show HN: Kastor – Terraform-style specs for AI agents
Kastor is "Terraform for AI agents." Agents today are defined imperatively inside frameworks (LangGraph, CrewAI) or clicked together in platform UIs (OpenAI Assistants, Bedrock Agents) — there is no vendor-neutral, versionable, reviewable source of truth. Kastor provides one: a typed, declarative spec ( .agent , .tool , .prompt files in HCL) and a Go toolchain with two paths — kastor build generates runnable projects for target frameworks, and kastor plan / kastor apply reconcile agents as long-lived resources on hosted platforms, with state, diffs, and drift detection.
This is not another agent runtime/framework.
Install script (verifies the release checksum, installs to /usr/local/bin or ~/.local/bin , never sudo):
Or download an archive for your platform from the releases page , verify it against checksums.txt , and put the kastor binary on your PATH.
Prerequisites: Go 1.26+, Python 3.11+, an OpenAI API key, and a Tavily API key (the example's search tool runs against Tavily's hosted MCP server).
Compile the spec to a LangGraph project: