Auto PR from Dev to Default Branch

Description

This GitHub Action automatically creates or updates a Pull Request from a development branch to the default branch, generates descriptive PR content with OpenAI, Claude or OpenRouter, and adds relevant reviewers.

Features

• 🔄 Automatically creates or updates a PR from dev to the default branch
• 🤖 Generates PR descriptions with OpenAI (default), Claude or OpenRouter — one script per provider in providers/
• 👥 Automatically adds relevant reviewers
• 📅 Sets PR title with current date (e.g., "Release v2023.05.25")

Inputs

Name	Description	Required	Default
provider	openai, claude or open-router (env AI_PROVIDER)	No	'openai'
model	Model for the provider (env AI_MODEL)	No	openai: 'gpt-6-luna', claude: 'claude-haiku-5-5', open-router: 'deepseek/deepseek-v4.1-flash'
openai_api_key	OpenAI API key (env OPENAI_API_KEY)	For openai	N/A
anthropic_api_key	Anthropic API key (env ANTHROPIC_API_KEY / CLAUDE_API_KEY)	For claude	N/A
anthropic_workspace_id	Only for Anthropic keys not scoped to a workspace (env ANTHROPIC_WORKSPACE_ID)	No	N/A
openrouter_api_key	OpenRouter API key (env OPENROUTER_API_KEY)	For open-router	N/A
openai_model	Deprecated alias of model for openai	No	N/A
github_token	GitHub Personal Access Token with repo permissions	Yes	N/A
dev_branch	Name of the development branch	No	'dev'
max_diff_bytes	Max size (bytes) of the diff payload sent to the model	No	'200000'

Outputs

Name	Description
pr_number	The number of the pull request created or updated

Usage

To use this action in your workflow, add the following step:

- name: Auto PR from Dev to Default
  uses: yuri-val/auto-pr-action@v1
  with:
    openai_api_key: ${{ secrets.OPENAI_API_KEY }}
    model: gpt-6-luna  # Optional, the openai default
    github_token: ${{ secrets.GITHUB_TOKEN }}
    dev_branch: dev  # Optional, defaults to 'dev'

Make sure to set up the secret for your provider (OPENAI_API_KEY, ANTHROPIC_API_KEY or OPENROUTER_API_KEY).

To use another provider, set it by input or once for the whole job by environment variable (inputs win):

    env:
      AI_PROVIDER: claude
      ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}

Which model writes best

Measured 2026-10-10 on three real PRs and one 5-commit release (all eight candidates followed the output rules; times and costs are per description):

Provider / model	Character	Avg time	Cost
openai / gpt-6-luna	shortest, accurate, fewest tokens	3.5 s	$0.0007
openai / gpt-5.6-luna	accurate, somewhat generic	4.7 s	$0.0016
claude / claude-haiku-5-5	most specific; the only model to catch every non-obvious change (e.g. a changed default with an upgrade note)	4.7 s	$0.0014
open-router / deepseek/deepseek-v4.1-flash	detailed and accurate	4.4 s	$0.0028
open-router / z-ai/glm-5.3-flash	detailed, occasional overstatement	13.9 s	$0.0012
open-router / xiaomi/mimo-v2.6-flash	detailed, slower	15.8 s	$0.0011
open-router / google/gemini-3.8-flash	concise, odd grouping, most expensive	4.6 s	$0.0067
open-router / qwen/qwen3.8-flash	long, very slow	57.9 s	$0.0025

Example Workflow Using Your Custom Action

Create a workflow file in your repository (e.g., .github/workflows/auto-pr.yml):

name: Auto PR from dev to default

on:
  push:
    branches:
      - dev

jobs:
  auto-pr:
    runs-on: ubuntu-latest
    # The PR is created with the PAT; the job token only needs to read the repo.
    permissions:
      contents: read
    steps:
      - name: Run Auto PR Action
        uses: yuri-val/auto-pr-action@v1
        with:
          openai_api_key: ${{ secrets.OPENAI_API_KEY }}
          github_token: ${{ secrets.PAT_TOKEN }}
          dev_branch: 'dev'  # Optional, defaults to 'dev'

How it works

1. Checks out the repository
2. Sets up Git configuration
3. Determines the default branch
4. Generates a diff between the dev and default branches
5. Uses the chosen provider (OpenAI, Claude or OpenRouter) to generate a descriptive PR content
6. Creates a new PR or updates an existing one
7. Adds relevant reviewers to the PR — the commit authors (real users only; bots and the organisation account are skipped), plus the repository owner for personal repositories

What is sent to the provider

The commit log, the per-file diffstat and the diff between the branches, capped at max_diff_bytes. The contents of secret-bearing files — .env*, *.pem, *.key, *.p12/*.pfx/*.jks, SSH keys, .npmrc/.netrc, credentials.yml*/secrets.yml* and similar — are excluded from the diff; they appear in the diffstat by name only. Generated files — dist/, *.min.js/*.min.css, source maps and lockfiles (package-lock.json, yarn.lock, Gemfile.lock, go.sum, ...) — are left out of the diff too, so a rebuilt bundle cannot push the real changes out of the max_diff_bytes budget; they also stay in the diffstat.

GitHub Workflow Description (Development Workflow)

Branch Structure

1. Default Branch: main or master
2. Development Branch: dev
3. Feature Branches: Multiple branches like feature/new_awesome_feature, feature/new_files, etc.

Workflow Steps

1. Branch Creation:

   • The dev branch is created from the default branch (main or master).
   • dev always contains all commits from the default branch.

2. Feature Development:

   • Multiple feature branches are created from dev.
   • Examples: feature/new_awesome_feature, feature/new_files, etc.
   • Developers work on these feature branches.

3. Feature Integration:

   • When a feature is complete, it is merged into the dev branch.

4. Automated Pull Request Creation/Update:

   • On every merge to dev (or any push to dev):
     • An automated process creates or updates a Pull Request from dev to the default branch (main or master).
     • The Pull Request description is automatically generated by the configured provider (OpenAI by default).
     • This ensures that the default branch is always aware of changes in dev.

5. Continuous Integration:

   • The dev branch continuously integrates new features.
   • The automated PR to the default branch is kept up-to-date with these changes.

6. Review and Merge:

   • The auto-generated PR can be reviewed and eventually merged into the default branch when ready.

This workflow allows for organized feature development, continuous integration into the dev branch, and an always up-to-date PR to the default branch with AI-generated descriptions for easy review and merging.

License

MIT License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

This README.md provides an overview of your GitHub Action, including its features, inputs, outputs, and usage instructions. It also briefly explains how the action works and includes sections for licensing and contributions.

You may want to adjust the "Usage" section to reflect the correct GitHub username or organization where this action will be published. Also, if you haven't already, you might want to add a LICENSE file to your repository.

Feel free to modify this README to better fit your project's specific needs or to add any additional information you think would be helpful for users of your GitHub Action.