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README.md

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+# Codex Bot
+
+This is an automated code review bot for this Gitea instance.
+
+It watches pull request comments and can run an AI-assisted review when explicitly requested.
+
+## Usage
+
+Comment this on a pull request:
+
+```text
+@codex review
+````
+
+The bot will inspect the PR diff and reply with a review summary.
+
+## What it checks
+
+Codex focuses on practical review issues:
+
+* bugs introduced by the PR
+* security problems
+* missing validation or permission checks
+* risky logic changes
+* broken edge cases
+* missing or weak tests
+* possible regressions
+
+It does **not** replace human review. Treat its comments as suggestions.
+
+## Commands
+
+```text
+@codex review
+```
+
+Run a normal review.
+
+```text
+@codex review security
+```
+
+Focus more heavily on security issues.
+
+```text
+@codex review tests
+```
+
+Focus on missing or weak tests.
+
+## Behavior
+
+The bot only runs when mentioned directly.
+
+It ignores its own comments to avoid loops.
+
+Reviews may take a moment depending on PR size.
+
+Large diffs may be summarized or skipped if they exceed the configured limits.
+
+## Account
+
+This account is used only for automated PR review comments.
+
+Do not assign issues or normal work to this user.