Lightweight Devin CLI in Bash with fzf session selection

devin

#!/usr/bin/env bash
#
# Lightweight Devin CLI in Bash
#
# Usage:
#   devin new "<prompt>"
#   devin message <session_id> "<text>"
#   devin list [--all]
#

set -e

# Check for DEVIN_API_KEY
if [ -z "$DEVIN_API_KEY" ]; then
  echo "⚠️  Please set DEVIN_API_KEY in your environment." >&2
  exit 1
fi

# Base URL and headers
BASE_URL="https://api.devin.ai/v1"
AUTH_HEADER="Authorization: Bearer $DEVIN_API_KEY"
CONTENT_HEADER="Content-Type: application/json"

cmd="$1"; shift || true

case "$cmd" in
  new)
    # devin new "<prompt>"
    prompt="$*"
    if [ -z "$prompt" ]; then
      echo "Usage: devin new \"<prompt>\"" >&2
      exit 1
    fi

    # Safely build JSON payload via jq
    payload=$(jq -n --arg p "$prompt" '{prompt: $p}')

    # POST /sessions
    resp=$(curl -s -H "$AUTH_HEADER" -H "$CONTENT_HEADER" -d "$payload" "$BASE_URL/sessions")

    # Extract and print the URL
    url=$(echo "$resp" | jq -r .url)
    echo "$url"
    ;;

  message)
    # devin message [<session_id>] "<text>"
    
    # Check if first argument looks like a session ID (starts with "devin-")
    if [[ "$1" =~ ^devin- ]]; then
      sid="$1"
      shift
      message_text="$*"
    else
      sid=""
      message_text="$*"
    fi
    
    if [ -z "$message_text" ]; then
      echo "Usage: devin message [<session_id>] \"<text>\"" >&2
      exit 1
    fi
    
    # Auto-select session if not provided
    if [ -z "$sid" ]; then
      # Get running sessions first
      resp=$(curl -s -H "$AUTH_HEADER" "$BASE_URL/sessions")
      running_sessions=$(echo "$resp" | jq -r '.sessions[] | select(.status == "running") | "\(.session_id)\t\(.status)\t\(.title)"')
      
      if [ -z "$running_sessions" ]; then
        # No running sessions, get all sessions
        all_sessions=$(echo "$resp" | jq -r '.sessions[] | "\(.session_id)\t\(.status)\t\(.title)"')
        if [ -z "$all_sessions" ]; then
          echo "❌  No sessions found" >&2
          exit 1
        fi
        
        session_count=$(echo "$all_sessions" | wc -l)
        if [ "$session_count" -eq 1 ]; then
          sid=$(echo "$all_sessions" | cut -f1)
        else
          if ! command -v fzf >/dev/null 2>&1; then
            echo "❌  Multiple sessions found. Please install fzf or provide a session_id explicitly:" >&2
            echo "   brew install fzf  # or your package manager" >&2
            echo "   devin message <session_id> \"<text>\"" >&2
            exit 1
          fi
          echo "📋  No running sessions. Select from all sessions:"
          selected=$(echo "$all_sessions" | fzf --with-nth=2,3 --delimiter='\t' | cut -f1)
          if [ -z "$selected" ]; then
            echo "❌  No session selected" >&2
            exit 1
          fi
          sid="$selected"
        fi
      else
        session_count=$(echo "$running_sessions" | wc -l)
        if [ "$session_count" -eq 1 ]; then
          sid=$(echo "$running_sessions" | cut -f1)
        else
          if ! command -v fzf >/dev/null 2>&1; then
            echo "❌  Multiple running sessions found. Please install fzf or provide a session_id explicitly:" >&2
            echo "   brew install fzf  # or your package manager" >&2
            echo "   devin message <session_id> \"<text>\"" >&2
            exit 1
          fi
          echo "🏃  Select running session:"
          selected=$(echo "$running_sessions" | fzf --with-nth=2,3 --delimiter='\t' | cut -f1)
          if [ -z "$selected" ]; then
            echo "❌  No session selected" >&2
            exit 1
          fi
          sid="$selected"
        fi
      fi
    fi

    # Safely build JSON payload via jq
    payload=$(jq -n --arg m "$message_text" '{message: $m}')

    # POST /session/{id}/message
    http_code=$(curl -s -o /dev/null -w "%{http_code}" \
      -X POST \
      -H "$AUTH_HEADER" -H "$CONTENT_HEADER" \
      -d "$payload" \
      "$BASE_URL/session/$sid/message")

    if [[ "$http_code" =~ ^2 ]]; then
      echo "✅  message sent"
    else
      echo "❌  HTTP $http_code" >&2
      exit 1
    fi
    ;;

  view)
    # devin view [<session_id>] [--tail [n]] [--follow]
    tail_count=""
    session_id=""
    follow_mode=false
    
    # Parse arguments
    while [ $# -gt 0 ]; do
      case "$1" in
        --tail)
          if [[ "$2" =~ ^[0-9]+$ ]]; then
            tail_count="$2"
            shift 2
          else
            tail_count="10"
            shift
          fi
          ;;
        --follow|-f)
          follow_mode=true
          # If --follow is used without --tail, default to showing last 10
          if [ -z "$tail_count" ]; then
            tail_count="10"
          fi
          shift
          ;;
        *)
          if [[ "$1" =~ ^devin- ]]; then
            session_id="$1"
          else
            echo "❌  Invalid session ID: $1" >&2
            echo "Usage: devin view [<session_id>] [--tail [n]] [--follow]" >&2
            exit 1
          fi
          shift
          ;;
      esac
    done
    
    # Auto-select session if not provided (optimized for view command)
    if [ -z "$session_id" ]; then
      echo "🔍  Fetching recent sessions..." >&2
      resp=$(curl -s --max-time 5 -H "$AUTH_HEADER" "$BASE_URL/sessions?limit=20")
      if [ $? -ne 0 ]; then
        echo "❌  Failed to fetch sessions (timeout or network error)" >&2
        echo "💡  Try specifying a session ID explicitly: devin view <session_id>" >&2
        exit 1
      fi
      running_sessions=$(echo "$resp" | jq -r '.sessions[] | select(.status == "running") | "\(.session_id)\t\(.status)\t\(.title)"')
      
      if [ -z "$running_sessions" ]; then
        all_sessions=$(echo "$resp" | jq -r '.sessions[] | "\(.session_id)\t\(.status)\t\(.title)"')
        if [ -z "$all_sessions" ]; then
          echo "❌  No sessions found" >&2
          exit 1
        fi
        
        session_count=$(echo "$all_sessions" | wc -l)
        if [ "$session_count" -eq 1 ]; then
          session_id=$(echo "$all_sessions" | cut -f1)
        else
          if ! command -v fzf >/dev/null 2>&1; then
            echo "❌  Multiple sessions found. Please install fzf or provide a session_id explicitly:" >&2
            echo "   brew install fzf  # or your package manager" >&2
            echo "   devin view <session_id> [--tail [n]]" >&2
            exit 1
          fi
          echo "📋  No running sessions. Select from all sessions:"
          selected=$(echo "$all_sessions" | fzf --with-nth=2,3 --delimiter='\t' | cut -f1)
          if [ -z "$selected" ]; then
            echo "❌  No session selected" >&2
            exit 1
          fi
          session_id="$selected"
        fi
      else
        session_count=$(echo "$running_sessions" | wc -l)
        if [ "$session_count" -eq 1 ]; then
          session_id=$(echo "$running_sessions" | cut -f1)
        else
          if ! command -v fzf >/dev/null 2>&1; then
            echo "❌  Multiple running sessions found. Please install fzf or provide a session_id explicitly:" >&2
            echo "   brew install fzf  # or your package manager" >&2
            echo "   devin view <session_id> [--tail [n]]" >&2
            exit 1
          fi
          echo "🏃  Select running session:"
          selected=$(echo "$running_sessions" | fzf --with-nth=2,3 --delimiter='\t' | cut -f1)
          if [ -z "$selected" ]; then
            echo "❌  No session selected" >&2
            exit 1
          fi
          session_id="$selected"
        fi
      fi
    fi
    
    # GET /session/{id}
    session_resp=$(curl -s -H "$AUTH_HEADER" "$BASE_URL/session/$session_id")
    
    # Check if response is valid JSON
    if ! echo "$session_resp" | jq . >/dev/null 2>&1; then
      echo "❌  API Error: $session_resp" >&2
      exit 1
    fi
    
    # Function to display session info and messages
    display_session() {
      local session_data="$1"
      local is_update="$2"
      
      if [ "$is_update" != "true" ]; then
        echo "📋  Session: $(echo "$session_data" | jq -r .title)"
        echo "🔗  Status: $(echo "$session_data" | jq -r .status)"
        if [ "$(echo "$session_data" | jq -r '.pull_request.url // empty')" != "" ]; then
          echo "🔗  PR: $(echo "$session_data" | jq -r .pull_request.url)"
        fi
        echo ""
      fi
      
      # Extract and display messages
      if [ -n "$tail_count" ]; then
        # Show only last n messages
        echo "$session_data" | jq -r ".messages | .[-$tail_count:] | .[] | \"\(.timestamp | split(\"T\")[1] | split(\":\")[0:2] | join(\":\")) [\(if (.type == \"user_message\" or .type == \"initial_user_message\") then \"👤 \" + (.username // \"User\") else \"🤖 Devin\" end)] \(.message)\""
      else
        # Show all messages
        echo "$session_data" | jq -r '.messages[] | "\(.timestamp | split("T")[1] | split(":")[0:2] | join(":")) [\(if (.type == "user_message" or .type == "initial_user_message") then "👤 " + (.username // "User") else "🤖 Devin" end)] \(.message)"'
      fi
    }
    
    # Display initial session info and messages
    display_session "$session_resp" false
    
    # Follow mode: continuously poll for new messages
    if [ "$follow_mode" = true ]; then
      echo ""
      echo "👀  Following session (Ctrl+C to stop)..."
      last_message_count=$(echo "$session_resp" | jq '.messages | length')
      
      while true; do
        sleep 3
        new_session_resp=$(curl -s --max-time 5 -H "$AUTH_HEADER" "$BASE_URL/session/$session_id" 2>/dev/null)
        
        if [ $? -eq 0 ] && echo "$new_session_resp" | jq . >/dev/null 2>&1; then
          new_message_count=$(echo "$new_session_resp" | jq '.messages | length')
          
          if [ "$new_message_count" -gt "$last_message_count" ]; then
            # New messages found, show only the new ones
            messages_to_show=$((new_message_count - last_message_count))
            echo "$new_session_resp" | jq -r ".messages | .[-$messages_to_show:] | .[] | \"\(.timestamp | split(\"T\")[1] | split(\":\")[0:2] | join(\":\")) [\(if (.type == \"user_message\" or .type == \"initial_user_message\") then \"👤 \" + (.username // \"User\") else \"🤖 Devin\" end)] \(.message)\""
            last_message_count="$new_message_count"
          fi
        fi
      done
    fi
    ;;

  list)
    # devin list [--all]
    show_all=false
    if [ "$1" == "--all" ]; then
      show_all=true
    fi

    # GET /sessions
    resp=$(curl -s -H "$AUTH_HEADER" "$BASE_URL/sessions")

    # Check if response is valid JSON
    if ! echo "$resp" | jq . >/dev/null 2>&1; then
      echo "❌  API Error: $resp" >&2
      exit 1
    fi

    if [ "$show_all" = true ]; then
      # Print every session
      echo "$resp" | jq -r '.sessions[] | "\(.session_id)\t\(.status)\t\(.title)"'
    else
      # Only show running sessions
      echo "$resp" | jq -r '.sessions[] | select(.status == "running") | "\(.session_id)\t\(.status)\t\(.title)"'
    fi
    ;;

  *)
    echo "Usage: devin {new \"<prompt>\" | message [<session_id>] \"<text>\" | view [<session_id>] [--tail [n]] [--follow] | list [--all]}" >&2
    exit 1
    ;;
esac

Lightweight Devin CLI in Bash

A comprehensive Bash script for interacting with the Devin API, featuring smart session management and real-time session viewing.

Features

• Smart Session Selection: Automatically selects single sessions or uses fzf for interactive selection
• Session Management: Create new sessions, send messages, list sessions
• Real-time Viewing: View session messages with optional tail and follow modes
• Error Handling: Robust error checking and user-friendly messages
• Auto-discovery: Prioritizes running sessions for better UX

Setup

1. Set your API key:

   export DEVIN_API_KEY="your-api-key-here"

2. Optional: Install fzf for interactive session selection:

   brew install fzf  # macOS
   # or your package manager

Usage

# Create a new session
devin new "implement user authentication system"

# Send message to auto-selected session
devin message "add unit tests for the auth module"

# Send message to specific session
devin message devin-abc123 "deploy to staging"

# View session messages (last 10 by default)
devin view --tail 20

# Follow a session in real-time
devin view --follow

# View specific session with follow mode
devin view devin-abc123 --tail 5 --follow

# List running sessions
devin list

# List all sessions
devin list --all

Commands

• new "<prompt>" - Create a new session with initial prompt
• message [session_id] "<text>" - Send message to session (auto-selects if no ID provided)
• view [session_id] [--tail [n]] [--follow] - View session messages with optional tailing and following
• list [--all] - List sessions (running only by default, --all for all sessions)

The script intelligently handles session selection, preferring running sessions and falling back to fzf selection when multiple options exist.