kestrel

kestrel

A terminal coding agent that plans, builds and heals. Streaming TUI, every major model behind one command, task-weight routing, self-healing verification loops, and a taste engine for frontends worth shipping.

Capabilities

Full TUI agent

An interactive terminal UI built on OpenTUI — the same stack as opencode. Streaming responses, live tool traces, session todos.

Multi-provider

Anthropic, OpenAI, Google, OpenRouter, Groq, xai, Z.ai GLM and local Ollama. Any provider/model id works.

Model routing

Prompts are classified by weight — fast, standard, heavy — and routed to the right model automatically. Switch instantly with /models.

Self-healing loops

After implementing, kestrel runs your typecheck, tests and build. Failures flow back into the loop until green, without weakening assertions.

Taste engine

A design critic reviews frontend changes — typography, spacing hierarchy, color discipline, interaction states — then repairs what fails.

Page mimicry

webfetch with format=scan audits any URL's structure and design tokens so kestrel can rebuild a site's frontend cleanly.

Fan-out fleet

The original harness lives on: dispatch one task to Claude Code, Cursor, Kimi and Codex in parallel worktrees, let a judge panel pick the winner.

Headless & SDK

kestrel serve exposes an HTTP+SSE API on localhost for scripts, editors and CI. One binary, no runtime required.

Install

# macOS / Linux — installs the agent CLI and the fleet harness
curl -fsSL https://raw.githubusercontent.com/velofy/kestrel/main/install.sh | bash

# or grab a single binary from Releases
kestrel --help

# store a provider key once
kestrel auth login anthropic

# go
kestrel                      # interactive TUI
kestrel run "build a landing page"   # one-shot, streams to stdout
kestrel serve                # headless HTTP+SSE on :4096