Pre-commit checks

dim check moves verification earlier — instead of noticing a problem after code lands, it scans your staged changes against active memory and guardrails before the commit.

Run it manually

dim check

It looks at git diff --cached and, for the files you changed:

• re-runs STATIC_CHECK evidence — a now-failing check means your change contradicts a claim;
• matches never guardrails against the added lines — flags a change that does what a guardrail forbids;
• reminds you about in-scope invariants/conventions that don't have an automated check.

Example output:

✗ [GUARDRAIL] 🚫 NEVER guardrail: the staged change appears to do exactly what this forbids
    "Never call the production payments API from src; use the sandbox client..."
~ [CONVENTION] CONVENTION covers a file you changed — make sure it still holds (no automated check attached)
    "Handlers never touch the DB directly"

✗ is a hard violation; ~ is an advisory reminder.

Warn vs block

By default dim check only warns (exit 0). To make hard violations fail:

dim check --block      # exit 1 on a hard violation

Check against a ref instead of the staged index:

dim check -r HEAD~1

Turn it into a pre-commit hook

aiDimag installs a pre-commit hook (additively) that runs dim check --pre-commit. It's a no-op until you opt in via the preCommitCheck setting in .aidimag/config.json:

preCommitCheck	Behavior on commit
unset / false	Hook does nothing
"warn" / true	Prints violations, allows the commit
"block"	Prints violations and blocks the commit on a hard violation

Set it:

{ "preCommitCheck": "block" }

Now a commit that trips a never guardrail is stopped:

✗ [GUARDRAIL] 🚫 NEVER guardrail: the staged change appears to do exactly what this forbids
dim check: 1 blocking violation(s). Resolve them or commit with --no-verify.

You can always bypass in a pinch with git commit --no-verify.

How it compares to dim verify

	dim verify	dim check
When	After code lands (and on hooks)	Before a commit, on staged changes
Scope	Whole store	Only memories touching changed files
Effect	Updates statuses	Reports/blocks; doesn't change statuses

Think of dim check as the shift-left companion to dim verify: catch the contradiction at author time, not after.

Next: Session briefings.