fspec CLI
A terminal environment and CLI for spec-driven development: Gherkin, a task board and several agents, written in Rust.
- 104 ★ on the repository
- Last commit
- MIT
Broad access
Why this level
- Built-in agents run commands and edit files with your account's rights.
- Daemon mode and the Telegram bridge open remote control of sessions.
Install
- Works in
Manual install
curl -fsSL https://raw.githubusercontent.com/sengac/fspec/main/scripts/install.sh | bashThe macOS and Linux script installs the binary into ~/.local/bin. Windows has install.ps1 and prebuilt binaries are on the releases page.
Access and checks
How we reviewBroad accessThe tool can change data, run commands or handle secrets.
- Built-in agents run commands and edit files with your account's rights.
- Daemon mode and the Telegram bridge open remote control of sessions.
This is third-party code. Review the repository files before installing.
What it does
fspec brings coding agents, a live task board and executable specifications into one terminal application. Requirements live beside the code: project foundations, work units, example maps, domain models and Gherkin scenarios linked to tests and implementation locations. Links can be audited and a task moves between stages through gates. You can run the whole application or use it as a command set for your own agent. `fspec init --agent=claude` or `--agent=codex` installs the workflow description and the `/fspec` command for Claude Code or `/prompts:fspec` for Codex, after which the agent manages specs through the CLI. It supports several sessions with separate Git worktrees, search of earlier conversations, command and file access rules, MCP connections, a daemon for long sessions and a separate Telegram bridge.
Who it is for. Teams writing code with agents who want requirements, tests and implementation linked inside the repository.
Good fit when
- A task starts from behavior examples that must become Gherkin scenarios.
- Several agents work on different tasks and each needs its own Git worktree.
- A Claude Code or Codex agent should manage specs through commands rather than by hand.
- You need to check that every scenario has a test and an implementation location.
Not a fit when
- The project is small and a process with stages and gates would slow it down.
- You need isolation: agents run with your account's rights and a sandbox must be set up separately.
- Installing through a `curl` script is unacceptable: use a prebuilt binary from the releases page.
Example request
Run `/fspec`, create a work unit for CSV export, write examples and Gherkin scenarios and link them to tests.Limitations
Agents run with the filesystem, shell and network rights of the account running fspec, so real isolation needs an OS or container sandbox. Command and file rules, checkpoints and worktrees help manage changes but do not replace backups and review. Full RPC access needs a matching daemon and connecting an MCP host has its own transport and authorization limits. The installer script downloads and runs code and should be inspected first. Building from source needs Rust, a compiler and `protoc`.
How to disable. Delete the fspec binary from `~/.local/bin` and the files `fspec init` created, including the `/fspec` command in the agent folder. Specs live in the repository and stay.
FAQ
How do I connect fspec to Claude Code?
In the project folder run `fspec init --agent=claude`, then call `/fspec` in Claude Code. The command loads `fspec bootstrap` and the agent can manage specs through the CLI.
How do I update fspec?
Run `fspec update --check` and then `fspec update`. The updater verifies the digest and replaces the binary in place.
Is there MCP access?
Yes, `fspec client --mcp` exposes service tools over stdio. Full RPC needs a matching daemon and the limits are in `docs/CLIENT_MCP.md`.
How do I restrict what agents do?
Configure block, allow and prompt rules for commands and files described in `docs/BLOCKLIST.md`. For real isolation use an OS or container sandbox.
Which platforms are supported?
There are prebuilt binaries and installers for macOS, Linux and Windows PowerShell. Building from source is only needed for development.
Discussion
No questions or reviews yet.
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README in short
The README covers features, installation, external agent mode, a safety section and building. Detailed topics sit in `docs/` and the Telegram bridge is in the `bridge` folder.