[plan] Add check-validator-sizes Makefile target to enforce 300-line limit #21481

Objective

Add a check-validator-sizes Makefile target that enforces the 300-line hard limit for validator files documented in AGENTS.md, and integrate it into the CI/lint chain.

Context

From discussion #21398 (Repository Quality Improvement Report - Validator File Size Compliance). The 300-line hard limit is documented in AGENTS.md but has no automated enforcement. A lightweight check in the Makefile would prevent future regressions after the current violations (Tasks 1–3) are fixed.

Approach

Add the following target to the Makefile:

## check-validator-sizes: Verify validator files do not exceed 300 lines (AGENTS.md hard limit)
check-validator-sizes:
	`@echo` "Checking validator file sizes..."
	`@violations`=$$(find ./pkg -type f -name "*valid*.go" ! -name "*_test.go" -exec wc -l {} \; | awk '$$1 > 300 {print $$1, $$2}' | sort -rn); \
	if [ -n "$$violations" ]; then \
		echo "❌ Validator files exceeding 300-line limit (AGENTS.md §Validation Complexity Guidelines):"; \
		echo "$$violations"; \
		exit 1; \
	else \
		echo "✅ All validator files within 300-line limit"; \
	fi

Then add check-validator-sizes to the lint target's dependencies (or to agent-finish) so it runs automatically.

Important: This task should be completed after the split tasks (Split expression_validation.go, Split strict_mode_validation.go, Split permissions_validation.go) have merged, so the check passes on the first run in CI.

Files to Modify

• Update: Makefile — add check-validator-sizes target and wire it into lint or agent-finish

Acceptance Criteria

• make check-validator-sizes target exists and works
• The target prints filename and line count for each violation
• The target exits with non-zero status when violations are found
• The target is included in make lint or make agent-finish
• A comment in the Makefile references the AGENTS.md guideline
• The CI passes (all current violations from the split tasks should be resolved first)

Generated by Plan Command for issue #discussion #21398 · ◷

• expires on Mar 19, 2026, 11:46 PM UTC