cake

cake is a headless AI coding assistant for the terminal. It behaves like a Unix filter: provide a task, let the model inspect and modify the working tree, receive the result, and exit.

Cake supports OpenAI-compatible Chat Completions and Responses APIs, sandboxed tool execution, persisted conversations, machine-readable output, project instructions, hooks, skills, and user-defined tools.

Install

Cake requires a current Rust toolchain:

git clone https://github.com/travisennis/cake.git
cd cake
cargo build --release

The binary is written to target/release/cake. Contributors should follow CONTRIBUTING.md instead.

Configure a model

Create $XDG_CONFIG_HOME/cake/settings.toml, or ~/.config/cake/settings.toml when XDG_CONFIG_HOME is unset:

default_model = "openrouter"

[[models]]
name = "openrouter"
model = "openai/gpt-5"
base_url = "https://openrouter.ai/api/v1/"
api_key_env = "OPENROUTER_API_KEY"
api_type = "chat_completions"

Then export the API key named by api_key_env:

export OPENROUTER_API_KEY="..."

Project settings may be placed in .cake/settings.toml. See Configuration for model fields, precedence, profiles, skills, prompts, hooks, and toolbox tools.

Use cake

# Prompt argument
cake "Explain the architecture"

# Pipe context while keeping the task separate
git diff --staged | cake "Review this change"

# Read the complete prompt from stdin
cake - < prompt.md

# Select a configured model
cake --model openrouter "Fix the failing test"

Run cake --help for the authoritative flag list.

Sessions

Runs are persisted by default:

cake "Start the refactor"
cake --continue "Finish it"
cake --resume <UUID> "Try another approach"
cake --fork <UUID> "Explore this without changing the original session"

Use --no-session for an ephemeral run. Session and output compatibility contracts are documented in Integrations.

Worktrees

--worktree [NAME] runs the task in an isolated Git worktree. Files matching patterns in a repository-root .worktreeinclude are copied into a newly created worktree. Symlinks are never followed: symlinked directories and files are skipped, which bounds traversal against symlink cycles and keeps collection inside the repository.

cake --worktree experiment "Implement the change"

Cake removes an unchanged worktree when the task finishes and retains one with uncommitted changes or new commits.

Machine-readable output

cake --output-format json "Summarize this repository" | jq '.result'
cake --output-format stream-json "Run the tests" | jq -c '.type'
cake --output-schema result.schema.json "Return structured findings"

json emits one completion object. stream-json emits newline-delimited task events as they happen. --output-schema constrains only the final model response.

Sandboxing

Model-generated Bash commands use workspace-write sandboxing by default. Select read-only, workspace-write, or danger-full-access with --sandbox.

The sandbox is a filesystem boundary, not a network boundary. Hooks and toolbox executables are trusted extensions and run outside the Bash sandbox. Read Security before changing permissions or enabling extensions.

Project instructions and extensions

• AGENTS.md supplies project-specific agent instructions.
• SKILL.md files provide instructions loaded on demand.
• hooks.json files run local commands at lifecycle events.
• Toolbox executables register additional tb__* tools.
• system.md can replace the built-in system prompt.

Configuration and precedence are in Configuration; extension protocols are in Integrations.

Documentation

Need	Authority
Configure and operate cake	Configuration
Consume sessions, JSON output, hooks, or toolbox protocols	Integrations
Understand permissions and trust boundaries	Security
Understand durable system boundaries	Architecture
Contribute changes	Contributing
Understand past decisions	ADR archive

Platform support

Cake is developed and primarily validated on macOS. Linux builds include Landlock support, but CI provides less runtime coverage than on macOS.

License

Cake is licensed under the MIT License.