[Workers AI] Restrict select models to Workers Paid plan

[mchenco]

Summary

Kimi K2.6, Kimi K2.7 Code, and GLM-5.2 are no longer available on the Workers Free plan and now require the Workers Paid plan. On the Free plan, requests to these models return a 403 (internal error 5035) prompting an upgrade.

This PR documents that change:

• Changelog entry announcing the restriction, the rationale (prioritizing capacity, fewer 429/3040 errors), and Free-plan alternatives.
• Errors page — new 5035 / 403 row.
• Pricing page — note listing the paid-only models.
• Model detail pages — a caution Aside (via a new reusable partial) on the three affected models, wired in through ModelDetailPage.astro.

Documentation checklist

• Is there a changelog entry (guidelines)? If you don't add one for something awesome and new (however small) — how will our customers find out? Changelogs are automatically posted to RSS feeds, the Discord, and X.
• The change adheres to the documentation style guide.

[github-actions]

This pull request requires reviews from CODEOWNERS as it changes files that match the following patterns:

Pattern	Owners
*.astro	@cloudflare/content-engineering, @kodster28
/src/content/changelog/	@cloudflare/pm-changelogs, @cloudflare/product-owners, @hoan-pom
/src/content/docs/workers-ai/	@rita3ko, @craigsdennis, @mchenco, @zeke, @superhighfives, @mattrothenberg, @ethulia, @aninibread, @kflansburg, @cloudflare/product-owners
*	@cloudflare/product-owners

[github-actions]

Preview URL: https://438efc57.preview.developers.cloudflare.com
Preview Branch URL: https://mchen-wai-workers-free.preview.developers.cloudflare.com

Files with changes (up to 15)

Original Link	Updated Link
https://developers.cloudflare.com/changelog/post/2026-07-28-models-require-workers-paid/	https://mchen-wai-workers-free.preview.developers.cloudflare.com/changelog/post/2026-07-28-models-require-workers-paid/
https://developers.cloudflare.com/workers-ai/platform/pricing/	https://mchen-wai-workers-free.preview.developers.cloudflare.com/workers-ai/platform/pricing/
https://developers.cloudflare.com/workers-ai/platform/errors/	https://mchen-wai-workers-free.preview.developers.cloudflare.com/workers-ai/platform/errors/

[cloudflare-docs-bot]

Review

⚠️ Part of the review could not complete in commit 438efc5 — it will retry on the next push.

Code Review

This code review is in beta and may not always be helpful — use your judgment.

_{No code review issues found.}

Conventions

❌ This review could not complete this run; results may be incomplete. It will retry on the next push.

Style Guide Review

_{No style-guide issues found.}

Commands

Only codeowners can run commands. Post a comment with the command to trigger it.

Command	Description
/review	Runs a review now. Incremental if a prior review exists, full if not.
/full-review	Re-reviews the entire PR diff from scratch, ignoring incremental history. Useful after a rebase, when you want a fresh review, or if the bot gets out of sync and reports issues that no longer exist.
/ignore-review-limit	Permanently lifts the 2-review automatic limit for this PR. Future pushes will trigger reviews as normal.
/disable-auto-review	Stops automatic reviews from triggering on future pushes to this PR. Codeowners can still run /review or /full-review manually.
/rebase	Rebases the PR branch against production. On conflict, attempts to resolve automatically using AI. Stops with an explanation if confidence is not high enough.