validate/lint have no check for "declared but never read" metadata — three instances found in one app in a day #4698

Reported from HotCRM, where a backlog sweep turned up the same failure shape five times in one day. Each instance passed os validate, os lint, tsc, and a full test suite. Filing the pattern rather than the instances, because the instances are app-side and the blind spot is not.

The shape

A key is authored, is schema-valid, reads as meaningful to anyone opening the file — and is never consumed by the runtime. The declaration and the behaviour disagree, and nothing in the toolchain notices, because every check verifies that what is declared is well-formed, never that it is read.

Three measured instances

1. decision node config.condition (singular). Every one of HotCRM's 24 flows spells a decision node's test as config.condition. The builtin decision executor reads config.conditions — plural array — and the edges. So the singular key is inert on all of them; branching happens to be correct only because the same expression is duplicated on the outgoing edges. Passes validate and lint. (hotcrm#642)

2. Table-level { fields: ['name'], unique: true } on a tenant-scoped object. normalizeDeclaredIndex() keeps declared-index columns verbatim, so this emits a platform-wide UNIQUE (name); only field-level unique: true gets the (organization_id, …) composite. The result is that two organizations cannot both have an account named "Acme Corp" — a multi-tenancy defect authored in one line that looks identical to the correct spelling. The existing unique/double-declaration lint fires only when both forms are present, so an object carrying only the table-level form gets no diagnostic at all. (hotcrm#625)

3. has(...) inside a sharing-rule condition. Sharing conditions are compiled to pushdown filters via compileCelToFilter; function calls are outside the translatable subset, so a guarded rule becomes untranslatable and the seeder skips it — the rule exists in metadata, is absent from sys_sharing_rule, and the only signal is one WARN line at boot. An author following the guidance that is correct for object validations produces silently inert security metadata. (hotcrm#621, #633)

Two more from the same sweep, same shape, different mechanism: a validation predicate that aborts is skipped rather than failed (objectstack#4649), and a flow variable that is declared is not thereby bound (objectstack#4697).

Why this is a platform concern

The app-side fixes are all in. What is not fixed is that the next app — or the next agent writing metadata for this one — will author the same shapes and get the same silence. These are exactly the errors generated metadata is most prone to: each is a plausible-looking key that a model would produce by analogy from a neighbouring declaration.

Suggested direction

A conservative "unread key" diagnostic would have caught instances 1 and 3 outright: for each metadata node type, the set of keys the runtime actually consumes is knowable from the executors, and a key outside that set is either a typo or a misconception. Instance 2 wants a narrower rule — a declared unique index on a tenant-scoped object whose columns do not lead with the tenant field is almost certainly a mistake, and the existing lint already knows the concept, it just only fires in the two-declaration case.

Whatever the mechanism, the useful invariant is the one the ledger discipline already applies to spec properties: a key that nothing reads should not validate clean.