#+TITLE: forge-llm
#+AUTHOR: Roger Gonzalez
#+EMAIL: roger@rogs.me

* forge-llm
:PROPERTIES:
:ID:       81db1fd1-a5db-4201-9113-72889f7c7829
:END:

Generate Pull Request descriptions for Forge using LLM providers through the [[https://github.com/ahyatt/llm][llm]] package.

[[https://gitlab.com/uploads/-/system/project/avatar/67959042/logo.png]]

** Overview
:PROPERTIES:
:ID:       e5e5a1d0-cf5a-4f45-8d4c-f2f75339bf9a
:END:

~forge-llm~ is an Emacs package that integrates Large Language Models (LLMs) with Forge, a Magit interface to GitHub and GitLab forges. This package helps you generate high-quality Pull Request descriptions based on your git diff and repository PR templates.

Main features:
- Automatically finds and uses your repository's PR template
- Generates PR descriptions based on git diffs between branches
- Seamless integration with Forge's PR creation workflow
- Supports any LLM provider supported by the ~llm~ package
- Stream LLM responses in real-time

** Dependencies
:PROPERTIES:
:ID:       f30fedc1-a24a-4308-bc78-6f9c01857c18
:END:

- [[https://magit.vc/][Magit]] and [[https://github.com/magit/forge][Forge]]
- [[https://github.com/ahyatt/llm][llm]]
- Emacs 25.1+

** Installation
:PROPERTIES:
:ID:       a4cfca4c-6029-445a-9e1d-88293ddaaff7
:END:

*** Using straight.el with use-package
:PROPERTIES:
:ID:       0c4a74cd-f752-4b3f-a729-0cc5a34f3d38
:END:

#+begin_src emacs-lisp
(use-package forge-llm
  :straight (:host gitlab :repo "rogs/forge-llm")
  :after forge
  :config
  (forge-llm-setup))
#+end_src

*** Using MELPA (once available)
:PROPERTIES:
:ID:       0e561e53-10f6-4a0b-90e3-46094124aeb2
:END:

#+begin_src emacs-lisp
(use-package forge-llm
  :ensure t
  :after forge
  :config
  (forge-llm-setup))
#+end_src

*** Manual installation
:PROPERTIES:
:ID:       b91cfecf-04a3-43c8-96d3-dea082e5ed6e
:END:

Clone the repository:

#+begin_src shell
git clone https://gitlab.com/rogs/forge-llm.git ~/.emacs.d/site-lisp/forge-llm
#+end_src

Add to your Emacs configuration:

#+begin_src emacs-lisp
(add-to-list 'load-path "~/.emacs.d/site-lisp/forge-llm")
(require 'forge-llm)
(forge-llm-setup)
#+end_src

** Setting up LLM providers
:PROPERTIES:
:ID:       842282e1-4760-4687-96a1-4c15adb9a13d
:END:

~forge-llm~ depends on the [[https://github.com/ahyatt/llm][llm]] package for LLM integration. You'll need to set up at least one LLM provider. Please refer to the [[https://github.com/ahyatt/llm?tab=readme-ov-file#setting-up-providers][llm documentation]] for detailed instructions.

*** Example: OpenAI provider
:PROPERTIES:
:ID:       108c5560-65ad-49e1-8c02-d4c0493bb2b2
:END:

First, create an [[https://platform.openai.com/account/api-keys][OpenAI API key]]. Then configure the ~llm~ OpenAI provider:

#+begin_src emacs-lisp
(require 'llm-openai)
(setq forge-llm-llm-provider (make-llm-openai :key "YOUR-OPENAI-KEY"))
#+end_src

*** Example: Anthropic provider
:PROPERTIES:
:ID:       b9728ac5-f5c0-4d6b-8d3e-a4b7c3d9e1f0
:END:

To use Claude models from Anthropic:

#+begin_src emacs-lisp
(require 'llm-claude)
(setq forge-llm-llm-provider (make-llm-claude :key "YOUR-ANTHROPIC-KEY" :chat-model "claude-3-7-sonnet-20250219"))
#+end_src

*** Using auth-source for API keys (recommended)
:PROPERTIES:
:ID:       59f84b84-ce44-4208-8531-56992cae847e
:END:

For better security, use Emacs ~auth-source~ to store your API keys:

#+begin_src emacs-lisp
(use-package llm
  :ensure t
  :config
  (setq llm-warn-on-nonfree nil))

(require 'llm-openai)

(use-package forge-llm
  :ensure t
  :after (forge llm)
  :custom
  (forge-llm-llm-provider
   (make-llm-openai
    :key (auth-source-pick-first-password
           :host "api.openai.com"
           :user "apikey")))
  :config
  (forge-llm-setup))
#+end_src

Content of ~.authinfo~ or ~.authinfo.gpg~:
#+begin_src
machine api.openai.com login apikey password YOUR-API-KEY-HERE
#+end_src

** Usage
:PROPERTIES:
:ID:       e6753914-01ee-41e9-bcdf-f3d6e75ee451
:END:

After setting up ~forge-llm~, the following commands will be available in Forge's pull request creation buffer:

| Key binding | Command                                    | Description                                           |
|-------------+--------------------------------------------+-------------------------------------------------------|
| C-c C-g     | forge-llm-generate-pr-description          | Generate a PR description (output to separate buffer) |
| C-c C-p     | forge-llm-generate-pr-description-at-point | Generate a PR description at the current point        |
| C-c C-t     | forge-llm-insert-template-at-point         | Insert the PR template at the current point           |

*** Workflow:
:PROPERTIES:
:ID:       d745d788-793a-4847-95d7-4f5105bc654d
:END:
1. Create a PR using Forge as normal (~forge-create-pullreq~)
2. In the PR creation buffer, position your cursor where you want to insert the PR description
3. Press ~C-c C-p~ to generate and insert a PR description based on your changes
4. Edit the description as needed and submit the PR

*** Canceling Generation:
:PROPERTIES:
:ID:       7ddfeaab-31a3-4476-b770-7c9751566d88
:END:
If you need to cancel an in-progress LLM request:
- ~M-x forge-llm-cancel-request~

** Customization
:PROPERTIES:
:ID:       baff250b-65a2-48cf-ace8-af38996bd865
:END:

You can customize various aspects of ~forge-llm~ through the following variables:

*** PR Template Configuration
:PROPERTIES:
:ID:       ccb75625-c64d-47ad-adbe-77862b4ebbb5
:END:

- ~forge-llm-pr-template-paths~ - List of possible paths for PR/MR templates relative to repo root
  #+begin_src emacs-lisp
  (setq forge-llm-pr-template-paths
        '(".github/PULL_REQUEST_TEMPLATE.md"
          ".github/pull_request_template.md"
          "docs/pull_request_template.md"
          ".gitlab/merge_request_templates/default.md"))
  #+end_src

- ~forge-llm-default-pr-template~ - Default PR template to use when no template is found in the repository

*** LLM Provider Configuration
:PROPERTIES:
:ID:       8c3c77fb-a6ae-47bb-8c2b-2b82c2364d81
:END:

- ~forge-llm-llm-provider~ - LLM provider to use. Can be a provider object or a function that returns a provider object
  #+begin_src emacs-lisp
  (setq forge-llm-llm-provider (make-llm-openai :key "YOUR-API-KEY"))
  #+end_src

- ~forge-llm-temperature~ - Temperature for LLM responses (nil for provider default)
  #+begin_src emacs-lisp
  (setq forge-llm-temperature 0.7)
  #+end_src

- ~forge-llm-max-tokens~ - Maximum number of tokens for LLM responses (nil for provider default)
  #+begin_src emacs-lisp
  (setq forge-llm-max-tokens 1024)
  #+end_src

*** Prompt Configuration
:PROPERTIES:
:ID:       f0cb4a2b-d919-4fe0-b286-317b93084174
:END:

- ~forge-llm-pr-description-prompt~ - Prompt used to generate a PR description with the LLM. This prompt is formatted with the PR template and git diff.

  You can customize this prompt to match your project's PR description style:

  #+begin_src emacs-lisp
  (setq forge-llm-pr-description-prompt
        "Generate a PR description for the following changes.
  PR template:
  %s

  Git diff:
  ```
  %s
  ```

  Please generate a PR description that follows our team's style.")
  #+end_src

** Integration with Doom Emacs
:PROPERTIES:
:ID:       6c2a34d5-8e1a-4f7e-9c2b-1d9e7b8f3a1d
:END:

Add the following to your ~packages.el~:

#+begin_src emacs-lisp
(package! forge-llm)
#+end_src

And in your ~config.el~:

#+begin_src emacs-lisp
(require 'forge-llm)
(require 'llm-openai)
(setq forge-llm-llm-provider (make-llm-openai :key "OPENAI_KEY"))
#+end_src

Or any other LLM available in the [[https://github.com/ahyatt/llm][llm]] package.

** Troubleshooting
:PROPERTIES:
:ID:       30489ac7-98ed-4820-a780-83c239e427f6
:END:

- If you're having issues with the LLM provider, you can enable debug logging for ~llm~ by setting ~llm-log~ to ~t~.
- Check the ~*forge-llm-debug-prompt*~ buffer to see the exact prompt being sent to the LLM.
- Check the ~*forge-llm-output*~ buffer to see the raw output from the LLM.

*** Common Issues:
:PROPERTIES:
:ID:       4b2fd630-290e-4a95-8315-e8db4b6f4217
:END:

- *Error: "No LLM provider configured"*
  - Make sure you've set ~forge-llm-llm-provider~ to a valid provider object.
  - Ensure your API key is correct.

- *Error: "Failed to generate git diff"*
  - Ensure you're in a repository with valid head and base branches.
  - Check if the current directory is within a git repository.

- *PR Generation is too slow*
  - Consider using a faster model (like GPT-3.5-turbo instead of GPT-4).
  - Reduce ~forge-llm-max-tokens~ to limit the response size.

- *PR template not found*
  - Check if your PR template is in one of the paths listed in ~forge-llm-pr-template-paths~.
  - Add your custom template path if needed.

** Contributing
:PROPERTIES:
:ID:       398ecc9e-30c2-4af4-afc5-c793ab3bedaa
:END:

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

*** Development Setup
:PROPERTIES:
:ID:       237ac5d2-d323-4b7d-9c51-54760a3ccc53
:END:

1. Clone the repository:
   #+begin_src shell
   git clone https://gitlab.com/rogs/forge-llm.git
   cd forge-llm
   #+end_src

2. Install dependencies for development:
   - Ensure you have forge and llm packages

** Changelog
:PROPERTIES:
:ID:       a4c3b2d1-e9f8-4d2a-8c7b-1e9d8c7b1e9d
:END:

*** 0.1.0 (Initial Release)
:PROPERTIES:
:ID:       a061d47e-e8cd-42ea-8403-d7e15f8c1478
:END:
- Initial functionality for PR description generation
- Template detection for GitHub and GitLab repositories
- LLM integration via the ~llm~ package
- Commands for generating PR descriptions
- Customization options for templates and LLM providers

** License
:PROPERTIES:
:ID:       14189649-a22f-4cf8-9850-9a8bb62456d3
:END:

This project is licensed under the GNU General Public License version 3 - see the LICENSE file for details.