Add AI Instructions

.agents/skills/config-based-modularity

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+../../skills/config-based-modularity

AGENTS.md

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+# Agent Guidance
+
+This repository is `dhii/containers`, a PHP library of interoperable container utilities. Use `README.md` as the source of truth for package purpose, supported container types, and examples.
+
+## Project Context
+
+- For architecture involving service providers, keyed definitions, composition, overrides, extensions, scoped configuration, or modularity, use the local skill at `.agents/skills/config-based-modularity`.
+- The installable source for that skill is `skills/config-based-modularity`; `.agents/skills/config-based-modularity` is a symlink for local agent discovery.
+- Do not duplicate conceptual explanations from `README.md` or the skill. Refer to them and keep changes focused.
+
+## Development Checks
+
+Use the existing CI workflow as the authority for checks: `.github/workflows/ci.yml`.
+
+Relevant local commands are:
+
+```bash
+composer validate
+vendor/bin/phpunit
+./vendor/bin/phpcs -s --runtime-set ignore_warnings_on_exit 1
+vendor/bin/psalm
+```
+
+## Change Guidance
+
+- Preserve PHP 7.4 compatibility unless the project metadata changes.
+- Keep source changes aligned with the existing style rules in `phpcs.xml.dist` and type expectations in `psalm.xml.dist`.
+- When changing behavior, add or update tests under the appropriate suite from `phpunit.xml.dist`.
+- Avoid committing local opencode plan files under `.opencode/plans/`.