- Documentation

- Better error handling in case could not deduce repo url

docs/docs/tools/help_docs.md

@@ -0,0 +1,25 @@
+## Overview
+
+The `help_docs` tool answers a question based on a given relative path of documentation, either from the repository of this merge request or from a given one.
+It can be invoked manually by commenting on any PR:
+```
+/help_docs "..."
+```
+
+## Example usage
+
+![TODO help_docs on the documentation of this repository](https://codium.ai/images/pr_agent/help_docs_comment.png){width=512}
+
+![TODO help_docs on the documentation of another repository](https://codium.ai/images/pr_agent/help_docs_comment_implicit_git.png){width=512}
+
+![TODO help_docs](https://codium.ai/images/pr_agent/help_docs_result.png){width=512}
+
+## Configuration options
+
+Under the section `--pr_help_docs`, the [configuration file](https://github.com/Codium-ai/pr-agent/blob/main/pr_agent/settings/configuration.toml#L50) contains options to customize the 'help docs' tool:
+
+- `repo_url`: If not overwritten, will use the repo from where the context came from (issue or PR), otherwise - use the given repo as context.
+- `repo_default_branch`: The branch to use in case repo_url overwritten, otherwise - has no effect.
+- `docs_path`: Relative path from root of repository (either the one this PR has been issued for, or above repo url).
+- `exclude_root_readme`:  Whether or not to exclude the root README file for querying the model.
+- `supported_doc_exts` : Which file extensions should be included for the purpose of querying the model.