[MyPrototypeWhat]

Summary

AGENTS.md only covered adding a package; updating a package got a single sentence. This adds two branches agents already take here:

• Updating a package (step 1): keep the plugin ID, raise version, and call out a newly declared field that raises the minimum client version, since it drops older clients.
• New section "Change the checks or the docs", limited to conventions not visible from the files themselves:
  • a minimum version is the first released client that accepts the field. cq-viewer 1.4.0: white-model render, conversation folders, orbit around the pressed point #59 recorded 3.1.4 from a preview build, but the released 3.1.4 rejects session.read; Sync the package checks and docs with the MiniMax Code 3.1.5 Mini App contract #81 fixed it;
  • contract, rule, test, and docs change together, and the Verified against lines are updated;
  • the checker stays dependency-free, as stated in its first commit ("zero-dependency check toolchain");
  • CI validates every package, so a new error must keep existing packages at zero errors, otherwise ship it as a warning first;
  • contract changes go in their own PR.

The opening line now points to the new section.

Left out on purpose:

• the directory layout, which ls shows;
• the per-package size limits, which npm run check enforces and docs/package-contract.md documents.

Verification

• Every path and name in the new section exists:
  • each scripts/lib/rules/*.mjs has a test/<rule>.test.mjs;
  • all six docs/*.md carry a Verified against line;
  • package.json has no dependencies.
• npm run check: 87 tests pass, including the wording test, which scans AGENTS.md.

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