Show HN: Askance, a human-in-the-loop GUI for agentic coding

Askance, a new human-in-the-loop GUI for agentic coding, lets developers answer questions from AI coding agents like Claude Code via a local server and CLI, with support for Markdown, Mermaid diagrams, diffs, and push notifications. The tool, distributed as a single binary for Linux, Mac, and Windows via WSL, can be installed via a Nix flake or run manually, and includes setup instructions for systemd and launchd.

Askance is a simple and beautiful human-in-the-loop GUI for answering questions from an AI coding agent such as Claude Code, either in the browser or on the go with your phone. It works by combining a server which you run locally with a self-documenting command-line utility which your agent uses to put questions to you. The CLI blocks on your answer so your agent waits for you, you answer whenever you're ready. - 📊 See agent feedback in richly formatted Markdown with Mermaid diagrams. - ✅ Answer questions with a single click, and attach free text to any answer. - 📋 Decide on multi-factor tradeoffs by picking from a table. - 🔍 View diffs of uncommitted code right next to agent feedback. - 📱 Respond from your desktop or your phone. - 🔔 Get notified when an agent is waiting on you with push notifications. Add the following to your nix flake to install fully on nix. Imports the latest version as a nix flake inputs.askance = { url = "github:tobico/askance"; inputs.nixpkgs.follows = "nixpkgs"; }; The module comes from the input rather than from pkgs, so it has to be imported before it can be enabled. In your host's module list: modules = askance.nixosModules.askance { services.askance.enable = true; } ; This runs the server daemon under its own user, and adds the Askance CLI to every user's PATH . Askance is distributed as a single binary, which you download and run from your home folder. It runs on Linux, Mac, and Windows via WSL. mkdir -p ~/.local/bin && curl -fsSL -o ~/.local/bin/askance \ "https://github.com/tobico/askance/releases/latest/download/askance-$ uname -s | tr ' :upper: ' ' :lower: ' | sed s/darwin/macos/ -$ uname -m | sed -e s/x86 64/x64/ -e s/aarch64/arm64/ " \ && chmod +x ~/.local/bin/askance ~/.local/bin needs to be on your PATH , which on most systems it already is. You can run the server manually with askance serve ; by default it will listen on 127.0.0.1:8422 . Open http://127.0.0.1:8422/ http://127.0.0.1:8422/ and you'll find the pending list, which is where your agent's questions turn up. Askance server works fine when run manually, but for convenience you can add a systemd user unit to have it start automatically with your machine. ~/.config/systemd/user/askance.service : Unit Description=Askance — questions from coding agents to a human After=network.target Service ExecStart=%h/.local/bin/askance serve --listen 127.0.0.1:8422 \ --database %S/askance/askance.db StateDirectory=askance Restart=always RestartSec=5s NoNewPrivileges=true RestrictSUIDSGID=true UMask=0077 Install WantedBy=default.target Then start it: systemctl --user daemon-reload systemctl --user enable --now askance macOS doesn't have systemd; its equivalent is launchd. Create a per-user agent, running as you, in ~/Library/LaunchAgents/net.tobico.askance.plist . launchd doesn't expand ~ , so the paths are spelled out — replace you with your username: <?xml version="1.0" encoding="UTF-8"? < DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd" <plist version="1.0" <dict <key Label</key <string net.tobico.askance</string <key ProgramArguments</key <array <string /Users/you/.local/bin/askance</string <string serve</string <string --listen</string <string 127.0.0.1:8422</string <string --database</string <string /Users/you/Library/Application Support/askance/askance.db</string </array < -- Start at login, and come back if it dies — an agent is blocked on an answer for as long as the server is down. -- <key RunAtLoad</key <true/ <key KeepAlive</key <true/ </dict </plist launchctl bootstrap gui/$ id -u ~/Library/LaunchAgents/net.tobico.askance.plist launchctl print gui/$ id -u /net.tobico.askance The database's parent directory is created for you, so there's nothing to set up before the first start. Add the following to your ~/.claude/CLAUDE.md file or equivalent: Never use the AskUserQuestion tool. Put all questions and approvals to me through askance: run askance once per session for the guide and follow it, including the topic guides it requires. The askance CLI is self-documenting and will guide your agent with built-in guides on how to use it effectively as needed. Askance is designed to be especially useful in two situations: - When your agent asks you a lot of questions - When your agent leaves code uncommitted as an acceptance gate, asking your permission before committing it. In order to benefit from this, you need to actually have skills or prompts which instruct your agent to do those things. Two such skills are included as examples, but feel free to use whichever skills or prompting approach you prefer; Askance will adapt to it. Grilling — interviews you about a plan by asking a series of questions until a shared understanding is reached. Inspired by the Matt Pocock grilling skill https://github.com/mattpocock/skills Acceptance gate — puts a gate before committing code changes. The agent waits for your feedback and addresses it, only proceeding to commit the code with your express approval. When running Askance, it's vital to understand the security implications. It runs as a server on your machine, with no authentication system, and accepts text input which is passed directly to your agent without sanitization. What keeps it safe is making sure that your server is never made available to others. By default it runs bound to 127.0.0.1, meaning it can't be accessed from other machines. If you do want to access it from another machine your phone for example , the recommended approach is to proxy that connection through tailscale serve , which lets you use Tailscale's authentication to control access, and adds TLS encryption provided by Tailscale which is itself a requirement if you want to enable push notifications . With Tailscale installed, run the following to set up a Tailscale proxy to your Askance server. The --bg option makes it persistent across reboots. tailscale serve --bg 8422 Note: To receive notifications on iOS, you'll need to add the site to your home screen. On Mobile Safari, tap "...", "Share", "View More", then "Add to Home Screen". To check the current version, run askance --version . Installed with curl: run the install command again, which overwrites the binary in place, then restart the server — systemctl --user restart askance on Linux, or launchctl kickstart -k gui/$ id -u /net.tobico.askance on a Mac. Installed from the flake: Run nix flake update askance in your host configuration, then rebuild — the rebuild restarts the service for you. The database is untouched either way, so the Archive and your phone's push subscription come back with the new binary. The server also asks GitHub once a day whether a newer release exists, and puts a banner above the pending list when there is one; it never installs anything itself, and ASKANCE NO UPDATE CHECK turns the check off. Askance can be configured by environment variables or CLI options: | Variable | CLI Option | Used by | Default | What it is | |---|---|---|---|---| ASKANCE SERVER | --server | CLI | http://127.0.0.1:8422 | Base URL the CLI submits to and waits on. | ASKANCE LISTEN | --listen | server | 127.0.0.1:8422 | Address and port to bind. | ASKANCE DATABASE | --database | server | askance.db | SQLite database for Askance data. | ASKANCE NO UPDATE CHECK | --no-update-check | server | unset | Disables the automated daily check to GitHub to notify you of a new Askance release. | Deployment — running the server as a service, in full: the NixOS module this flake carries, and a systemd unit for a host that isn't NixOS. On your phone — tailscale serve , adding the site to your home screen, turning notifications on per device, and how the long waits behave through the proxy. Development — the dev shell, building the viewer, and the loop for working on Askance itself. Releasing — how a tag becomes the binaries the install command above fetches. CONTEXT.md — the project's vocabulary. Question Set, Preface, Answer, Response and the rest, defined once. MIT — see LICENSE /tobico/askance/blob/main/LICENSE .