feat(chore): Minimal github conventions (#1530)

ref: WEB-2430

Author: Marcosld

AGENTS.md

@@ -21,3 +21,10 @@ React component library for Telefonica's Design System.
 - If you create a new component always create a snippet for playroom.
 - If you add props to a component always update stories accordingly and add the new props to args and
   argTypes.
+
+---
+
+## GitHub conventions
+
+- Read [CONTRIBUTING](./CONTRIBUTING.md) before contributing to Mistica repo.
+- Always add the `AI` label to PRs where the code was written by an AI agent.

CONTRIBUTING.md

@@ -21,6 +21,13 @@ Don't hesitate to ask any questions and share your ideas
 We would love to accept your Pull Requests but please, before starting your development,
 [create an issue](https://github.com/Telefonica/mistica-web/issues/new/choose).
 
+- PR title must follow **conventional commits** format; the scope must be the affected **component name**
+  (e.g. `fix(TextField): ...`). If no component was affected but the change is internal you can use set
+  "Chore" as the component name. For allowed types check [lint action](./.github/workflows/lint-pr.yml).
+- PR description: concise summary of the problem and fix, ending with `Ref: <TICKET-ID>` (if there's a jira
+  ticket).
+- Always add reviewers `aweell`, `atabel`, `yceballost` and `Marcosld` to every PR.
+
 ## Bug reports
 
 If something is broken or not working as expected, let us know!