Jetpack Sync: Add AGENTS.md

[coder-karen]

Fixes SYNC-245

Proposed changes:

• This PR creates an initial AGENTS.md file for the Sync package, as well as a CLAUDE.md file with symlink.
• See the Linear issue for more background information.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

n/a

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

• This is mainly a case of reviewing the information added.
• However it can be tested, if you are using Claude code in your local development environment. With this PR applied you can make some asks to Claude to see if it can make a specified change to the Sync package - one that ideally requires some knowledge of what happens on WPcom as well. A simple example is 'I need to add a new option to the sync whitelist. Where should I add it? '. Claude should read the AGENTS.md file (you should see that it is doing this) - if not, ask it to. It should clarify that changes are needed on WPcom. It should also attempt to add tests by default for changes you make.

Changelog

• Generate changelog entries for this PR (using AI).

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ Add a "[Status]" label (In Progress, Needs Review, ...).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

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Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Make sure to test your changes on all platforms that it applies to. You're responsible for the quality of the code you ship.
3. You can use GitHub's Reviewers functionality to request a review.
4. When it's reviewed and merged, you will be pinged in Slack to deploy the changes to WordPress.com simple once the build is done.

If you have questions about anything, reach out in #jetpack-developers for guidance!

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack or WordPress.com Site Helper), and enable the add/sync-package-agents-md branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/sync-package-agents-md

bin/jetpack-downloader test jetpack-mu-wpcom-plugin add/sync-package-agents-md

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[jp-launch-control]

Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/packages/jetpack-mu-wpcom/src/features/agents-manager/class-agents-manager.php	233/346 (67.34%)	-0.58%	2 ❤️‍🩹

Full summary · PHP report · JS report

[Copilot]

Pull request overview

Adds initial AI-agent guidance documentation for the Sync package and ensures it’s excluded from production builds.

Changes:

• Added AGENTS.md with Sync architecture, testing, and WPcom interaction guidance.
• Added CLAUDE.MD pointer intended to reference AGENTS.md.
• Added changelog entry and marked agent docs as production-exclude.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
projects/packages/sync/changelog/pr-47304	Changelog entry describing internal documentation addition.
projects/packages/sync/CLAUDE.MD	Adds a single-line pointer to the agent guidance file.
projects/packages/sync/AGENTS.md	Introduces the agent guidance document for Sync.
projects/packages/sync/.gitattributes	Excludes agent docs from production artifacts.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

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