The `improve` tool scans the PR code changes, and automatically generates [meaningful](https://github.com/Codium-ai/pr-agent/blob/main/pr_agent/settings/pr_code_suggestions_prompts.toml#L41) suggestions for improving the PR code.
The tool can be triggered automatically every time a new PR is [opened](../usage-guide/automations_and_usage.md#github-app-automatic-tools-when-a-new-pr-is-opened), or it can be invoked manually by commenting on any PR:
Note that the `Apply this suggestion` checkbox, which interactively converts a suggestion into a commitable code comment, is available only for Qodo Merge💎 users.
To run the `improve` automatically when a PR is opened, define in a [configuration file](https://qodo-merge-docs.qodo.ai/usage-guide/configuration_options/#wiki-configuration-file):
- Indirect implementation - when the user implements the suggestion in their IDE environment. In this case, Qodo Merge will utilize, after each commit, a dedicated logic to identify if a suggestion was implemented, and will mark it as implemented.
In post-process, Qodo Merge counts the number of suggestions that were implemented, and provides general statistics and insights about the suggestions' impact on the PR process.
Qodo Merge employs an novel detection system to automatically [identify](https://qodo-merge-docs.qodo.ai/core-abilities/impact_evaluation/) AI code suggestions that PR authors have accepted and implemented.
Accepted suggestions are also automatically documented in a dedicated wiki page called `.pr_agent_accepted_suggestions`, allowing users to track historical changes, assess the tool's effectiveness, and learn from previously implemented recommendations in the repository.
An example [result](https://github.com/Codium-ai/pr-agent/wiki/.pr_agent_accepted_suggestions):
This dedicated wiki page will also serve as a foundation for future AI model improvements, allowing it to learn from historically implemented suggestions and generate more targeted, contextually relevant recommendations.
This feature is controlled by a boolean configuration parameter: `pr_code_suggestions.wiki_page_accepted_suggestions` (default is true).
!!! note "Wiki must be enabled"
While the aggregation process is automatic, GitHub repositories require a one-time manual wiki setup.
Instead, we leverage a dedicated private page, within your repository wiki, to track suggestions. This approach offers convenient secure suggestion tracking while avoiding pull requests or any noise to the main repository.
Another option to give additional guidance to the AI model is by creating a `best_practices.md` file, either in your repository's root directory or as a [**wiki page**](https://github.com/Codium-ai/pr-agent/wiki) (we recommend the wiki page, as editing and maintaining it over time is easier).
This page can contain a list of best practices, coding standards, and guidelines that are specific to your repo/organization.
The AI model will use this wiki page as a reference, and in case the PR code violates any of the guidelines, it will create additional suggestions, with a dedicated label: `Organization
- Keep the file relatively short, under 800 lines, since:
- AI models may not process effectively very long documents
- Long files tend to contain generic guidelines already known to AI
#### Local and global best practices
By default, Qodo Merge will look for a local `best_practices.md` wiki file in the root of the relevant local repo.
If you want to enable also a global `best_practices.md` wiki file, set first in the global configuration file:
```toml
[best_practices]
enable_global_best_practices = true
```
Then, create a `best_practices.md` wiki file in the root of [global](https://qodo-merge-docs.qodo.ai/usage-guide/configuration_options/#global-configuration-file) configuration repository, `pr-agent-settings`.
#### Best practices for multiple languages
For a git organization working with multiple programming languages, you can maintain a centralized global `best_practices.md` file containing language-specific guidelines.
When reviewing pull requests, Qodo Merge automatically identifies the programming language and applies the relevant best practices from this file.
### How to combine `extra instructions` and `best practices`
The `extra instructions` configuration is more related to the `improve` tool prompt. It can be used, for example, to avoid specific suggestions ("Don't suggest to add try-except block", "Ignore changes in toml files", ...) or to emphasize specific aspects or formats ("Answer in Japanese", "Give only short suggestions", ...)
In contrast, the `best_practices.md` file is a general guideline for the way code should be written in the repo.
Using a combination of both can help the AI model to provide relevant and tailored suggestions.
Each generated suggestion consists of three key elements:
1. A single-line summary of the proposed change
2. An expandable section containing a comprehensive description of the suggestion
3. A diff snippet showing the recommended code modification (before and after)
We advise users to apply critical analysis and judgment when implementing the proposed suggestions.
In addition to mistakes (which may happen, but are rare), sometimes the presented code modification may serve more as an _illustrative example_ than a direct applicable solution.
In such cases, we recommend prioritizing the suggestion's detailed description, using the diff snippet primarily as a supporting reference.
Our recommended approach for presenting code suggestions is through a [table](https://qodo-merge-docs.qodo.ai/tools/improve/#overview) (`--pr_code_suggestions.commitable_code_suggestions=false`).
We also offer a complementary **dual publishing mode**. When enabled, suggestions exceeding a certain score threshold are not only displayed in the table, but also presented as commitable PR comments.
Where x represents the minimum score threshold (>=) for suggestions to be presented as commitable PR comments in addition to the table. Default is -1 (disabled).
This reduces the visual footprint of the suggestions, and also indicates to the PR reviewer that the suggestions have been reviewed by the PR author, and don't require further attention.
!!! tip "Tip - Demanding self-review from the PR author 💎"
the tool can automatically add an approval when the PR author clicks the self-review checkbox.
- If you set the number of required reviewers for a PR to 2, this effectively means that the PR author must click the self-review checkbox before the PR can be merged (in addition to a human reviewer).
- If you keep the number of required reviewers for a PR to 1 and enable this configuration, this effectively means that the PR author can approve the PR by actively clicking the self-review checkbox.
To prevent unauthorized approvals, this configuration defaults to false, and cannot be altered through online comments; enabling requires a direct update to the configuration file and a commit to the repository. This ensures that utilizing the feature demands a deliberate documented decision by the repository owner.
Note: Chunking is primarily relevant for large PRs. For most PRs (up to 500 lines of code), Qodo Merge will be able to process the entire code in a single call.
<td>If set to true, suggestions will focus primarily on identifying and fixing code problems, and less on style considerations like best practices, maintainability, or readability. Default is true.</td>
<td>If set to true, the improve comment will be persistent, meaning that every new improve request will edit the previous one. Default is false.</td>
</tr>
<tr>
<td><b>suggestions_score_threshold</b></td>
<td> Any suggestion with importance score less than this threshold will be removed. Default is 0. Highly recommend not to set this value above 7-8, since above it may clip relevant suggestions that can be useful. </td>
</tr>
<tr>
<td><b>apply_suggestions_checkbox</b></td>
<td> Enable the checkbox to create a committable suggestion. Default is true.</td>
</tr>
<tr>
<td><b>enable_help_text</b></td>
<td>If set to true, the tool will display a help text in the comment. Default is true.</td>
</tr>
<tr>
<td><b>enable_chat_text</b></td>
<td>If set to true, the tool will display a reference to the PR chat in the comment. Default is true.</td>
<td>If set to true, the tool will automatically track accepted suggestions in a dedicated wiki page called `.pr_agent_accepted_suggestions`. Default is true.</td>
<td>If set to true, all code suggestions will have thumbs up and thumbs down buttons, to encourage users to provide feedback on the suggestions. Default is false.</td>
- AI models for code are getting better and better (Sonnet-3.5 and GPT-4), but they are not flawless. Not all the suggestions will be perfect, and a user should not accept all of them automatically. Critical reading and judgment are required.
- While mistakes of the AI are rare but can happen, a real benefit from the suggestions of the `improve` (and [`review`](https://qodo-merge-docs.qodo.ai/tools/review/)) tool is to catch, with high probability, **mistakes or bugs done by the PR author**, when they happen. So, it's a good practice to spend the needed ~30-60 seconds to review the suggestions, even if not all of them are always relevant.
- The hierarchical structure of the suggestions is designed to help the user to _quickly_ understand them, and to decide which ones are relevant and which are not:
- Only if the summarized suggestion description is relevant, the user should click on the collapsible, to read the full suggestion description with a code preview example.
- In addition, we recommend to use the [`extra_instructions`](https://qodo-merge-docs.qodo.ai/tools/improve/#extra-instructions-and-best-practices) field to guide the model to suggestions that are more relevant to the specific needs of the project.
- The interactive [PR chat](https://qodo-merge-docs.qodo.ai/chrome-extension/) also provides an easy way to get more tailored suggestions and feedback from the AI model.