blackbox

Blackbox CLI

Delegate coding tasks to Blackbox AI via the Hermes terminal. Blackbox is a multi-model coding agent CLI that dispatches tasks to multiple LLMs (Claude, Codex, Gemini, Blackbox Pro) and uses a judge to select the best implementation.

The CLI (npm @blackbox_ai/blackbox-cli, binary blackbox) is a TypeScript coding agent (forked from Gemini CLI) and supports interactive sessions, non-interactive one-shots, checkpointing, MCP, and vision model switching.

Prerequisites

• Node.js 20+ installed
• Blackbox CLI installed: npm install -g @blackbox_ai/blackbox-cli (binary: blackbox)
• API key from app.blackbox.ai/dashboard
• Configured: run blackbox configure and enter your API key
• Use pty=true in terminal calls — Blackbox CLI is an interactive terminal app

One-Shot Tasks

terminal(command="blackbox --prompt 'Add JWT authentication with refresh tokens to the Express API'", workdir="/path/to/project", pty=true)

For quick scratch work:

terminal(command="cd $(mktemp -d) && git init && blackbox --prompt 'Build a REST API for todos with SQLite'", pty=true)

Background Mode (Long Tasks)

For tasks that take minutes, use background mode so you can monitor progress:

# Start in background with PTY
terminal(command="blackbox --prompt 'Refactor the auth module to use OAuth 2.0'", workdir="~/project", background=true, pty=true)
# Returns session_id

# Monitor progress
process(action="poll", session_id="<id>")
process(action="log", session_id="<id>")

# Send input if Blackbox asks a question
process(action="submit", session_id="<id>", data="yes")

# Kill if needed
process(action="kill", session_id="<id>")

Checkpoints & Resume

Blackbox CLI has built-in checkpoint support for pausing and resuming tasks:

# After a task completes, Blackbox shows a checkpoint tag
# Resume with a follow-up task:
terminal(command="blackbox --resume-checkpoint 'task-abc123-2026-03-06' --prompt 'Now add rate limiting to the endpoints'", workdir="~/project", pty=true)

Session Commands

During an interactive session, use these commands:

PR Reviews

Clone to a temp directory to avoid modifying the working tree:

terminal(command="REVIEW=$(mktemp -d) && git clone https://github.com/user/repo.git $REVIEW && cd $REVIEW && gh pr checkout 42 && blackbox --prompt 'Review this PR against main. Check for bugs, security issues, and code quality.'", pty=true)

Parallel Work

Spawn multiple Blackbox instances for independent tasks:

terminal(command="blackbox --prompt 'Fix the login bug'", workdir="~/.hermes/cache/scratch/issue-1", background=true, pty=true)
terminal(command="blackbox --prompt 'Add unit tests for auth'", workdir="~/.hermes/cache/scratch/issue-2", background=true, pty=true)

# Monitor all
process(action="list")

Multi-Model Mode

Blackbox's unique feature is running the same task through multiple models and judging the results. Configure which models to use via blackbox configure — select multiple providers to enable the Chairman/judge workflow where the CLI evaluates outputs from different models and picks the best one.

Key Flags

Vision Support

Blackbox automatically detects images in input and can switch to multimodal analysis. VLM modes:

• "once" — Switch model for current query only
• "session" — Switch for entire session
• "persist" — Stay on current model (no switch)

Token Limits

Control token usage via .blackboxcli/settings.json:

{
  "sessionTokenLimit": 32000
}

Rules

1. Always use `pty=true` — Blackbox CLI is an interactive terminal app and will hang without a PTY
2. Use `workdir` — keep the agent focused on the right directory
3. Background for long tasks — use background=true and monitor with process tool
4. Don't interfere — monitor with poll/log, don't kill sessions because they're slow
5. Report results — after completion, check what changed and summarize for the user
6. Credits cost money — Blackbox uses a credit-based system; multi-model mode consumes credits faster
7. Check prerequisites — verify blackbox CLI is installed before attempting delegation