CtxCtl

Your coding agent pays for every byte of context.

A stateless context layer for coding agents: AST symbol slices instead of whole-file dumps, exec output compression instead of raw log walls — byte-stable output that keeps provider prompt caches hot. Optional ctxctl mcp adapter.

Read the docs

$ ctxctl outline src/server.rs

# src/server.rs [12 symbols, ~2.1 KB -> ~410 tokens, saved ~80%]

fn handle_request L:42-58 pub async fn handle_request(&self, id: u64)

struct Config L:60-71 pub struct Config {

fn validate L:73-88 fn validate(cfg: &Config) -> Result<(), Error> {

$ ctxctl symbol src/server.rs --name handle_request --compact

# handle_request src/server.rs:42-58 (58 tokens, saved ~85%)

pub async fn handle_request(&self, id: u64) -> Result<String, Error> { ... }

$ ctxctl exec "cargo build"

error[E0308]: mismatched types --> src/main.rs:12

... [34 lines omitted]

Saved ~70% (1,240 -> 372 tokens)

−33%session cost −84%log-analysis cost 91–95%smaller outlines

Scripted-agent benchmark, deepseek-v4-flash via OpenRouter, single run per arm.

Six commands, one job

Read only the symbol you need, compress what your commands print, never re-send a byte you already paid for.

outline

Symbol map of any file — names, kinds, line ranges, signatures — with token-savings stats.

ctxctl outline src/server.rs

symbol

One symbol’s verbatim slice from the original source by AST byte range. --compact folds the body.

ctxctl symbol src/server.rs --name handle_request --compact

read

Raw line-range slices when you know exactly which lines you want. No AST needed.

ctxctl read src/main.rs --lines 40-80

deps

Import/module dependency graph of a file, split into local and external targets.

ctxctl deps src/main.rs

exec

Run a command, collapse its output to key lines plus head/tail summary. The least conditional win.

ctxctl exec "cargo test" --keep "FAILED|passed"

mcp

Serve the same five commands as MCP tools over stdio for MCP-native agents.

ctxctl mcp

14 language backends via tree-sitter

.rs.ts.tsx.js.jsx.py.go.c.h.cpp.java.cs.rb.lua.html/.htm.css/.scss.md

Install

cargo install ctxctl

npm install -g ctxctl
# or
bun add -g ctxctl

Download the prebuilt binary for your platform from the releases page — also ships .deb, .rpm, .apk, and Arch packages.