JJ bookmark names via GPT

bm.sh

#!/usr/bin/env bash

# Generate bookmark names bases on jj change descriptions

# init vars
api_key="${OPENAI_API_KEY}"
base_rev="${1:-trunk()}"

if [ -z "$api_key" ]; then
  echo "Error: OPENAI_API_KEY environment variable not set" >&2
  exit 1
fi

# show actual trunk bookmark if default was used
if [ "$#" -eq 0 ]; then
  trunk_bookmark=$(jj log -r 'trunk()' -T 'local_bookmarks' --ignore-working-copy --no-graph)
  echo "Using default base revision: $trunk_bookmark"
fi

# get commit msgs since merge base
commit_msgs=$(jj log -T 'description ++ "-----\n"' --no-graph -r "heads(::@ & ::$base_rev)..@")

if [ -z "$commit_msgs" ]; then
  echo "Error: No commits found between @ and $base_rev" >&2
  exit 1
fi

# build request json properly with jq
request=$(jq -n \
  --arg msgs "$commit_msgs" \
  --arg sys_prompt "You are a helpful assistant that generates git/jj branch names. Generate short, descriptive branch names based on commit messages. Return JSON with a single 'branch_name' field. Use kebab-case. Never include ticket numbers. Keep names under 40 chars." \
  '{
    model: "gpt-4o-mini",
    messages: [
      {
        role: "system",
        content: $sys_prompt
      },
      {
        role: "user",
        content: ("Generate a branch name based on these commit messages:\n\n" + $msgs)
      }
    ],
    response_format: { type: "json_object" },
    temperature: 0.7
  }')

# call api
response=$(curl -s -X POST \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $api_key" \
  -d "$request" \
  https://api.openai.com/v1/chat/completions)

# extract name with better error handling
if ! suggested_name=$(echo "$response" | jq -r '.choices[0].message.content' | jq -r '.branch_name' 2>/dev/null); then
    echo "Error: Failed to parse API response" >&2
    echo "Raw response: $response" >&2
    exit 1
fi

if [ "$suggested_name" = "null" ] || [ -z "$suggested_name" ]; then
    echo "Error: API returned empty bookmark name" >&2
    echo "Raw response: $response" >&2
    exit 1
fi

suggested_name=$(echo "$suggested_name" | sed 's/[^a-zA-Z0-9-]/-/g')

# show suggestion & get user input
echo -e "\nSuggested bookmark name: $suggested_name"
echo -n "Accept suggested name? (press enter to accept or type new name): "
read -r user_input

branch_name=${user_input:-$suggested_name}

# create bookmark
jj bookmark create "$branch_name"
echo "Created bookmark '$branch_name'"