All four suppressed comments from Copilot's third pass of #1962. Each was
correct.
The candidate boundary omitted `vitest.shared.mts` — root-owned, imported by
every client's vitest config, and already treated as shared non-client source
by `verify:typecheck-coverage`. It imports only Node built-ins today, which
is exactly why the omission would have gone unnoticed until a third-party
import appeared there, resolved from the root, and skewed. Shared *files* are
now a first-class list beside the shared dirs.
The allowlist was a blanket exemption by name. Each entry's rationale
establishes that a patch/minor difference is benign, which is no evidence
that a React 18-vs-19 or Hono 4-vs-5 split would be — that is a different
type surface. Being listed now tolerates skew only *within a major version*;
a cross-major skew fails like anything else. Deriving the major from the
lockfile version keeps this automatic, with no per-package range to maintain
and bump. A version that can't be parsed is treated as "cannot prove same
major" and fails rather than passes.
`verify-format-coverage.mjs`'s comment overstated the vouching graph: the
three guards do not each check the others. This one checks both siblings;
each sibling checks only this one. Described as it actually works.
The AGENTS.md rule said to bump a shared dependency in "root + all four
clients", but launcher declares no zod and `findSkew` ignores installs where
a package is absent — so the rule as written asked for spurious dependencies.
Reworded to every install that *declares* it, and mirrored in
`.github/copilot-instructions.md`.
The failure output follows: it no longer advises adding a package that is
already allowlisted, saying "MAJOR skew" instead, and it names all three
shared sources rather than the two dirs.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3
From the suppressed comment on Copilot's second pass of #1962. Under-
approximating is the dangerous direction here: a package the scan misses
never enters the candidate set, so its skew passes the guard silently.
Three forms went unmatched. `import x = require("pkg")` and a bare
`require("pkg")` are the ordinary import syntax in `.cts` — which the
previous commit just admitted to the scan, so leaving them out would have
been an inconsistency introduced by that widening. A dynamic import carrying
import attributes (`import("pkg", { with: … })`) was missed because the
pattern required the closing paren. A static template literal
(`import(\`pkg\`)`) was missed for want of a backtick in the quote class.
Backticks are accepted only in the *call* forms. A `from` clause requires a
string literal, so allowing them there would buy nothing while reopening the
prose hazard the anchored specifier pattern closes: inline code in comments
is written with backticks throughout this codebase, and admitting it inflated
the derived set from 18 names to 41 with prose fragments (`tools`,
`connect()`, `messages`). Inert today, since a name absent from every
lockfile contributes nothing — but a prose word colliding with a real package
name would silently widen the set. Pinned with a regression test.
The real set is unchanged at 18, so these forms add no package today; they
close the syntax against the one that arrives later.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3
Both from Copilot's review of #1962.
The candidate-set enumeration matched only `.ts`/`.tsx`, while
`verify:format-coverage` and `verify:typecheck-coverage` both gate all four
TypeScript extensions. No `.mts`/`.cts` exists under `core/` or
`test-servers/src` today, which is exactly why the omission would have gone
unnoticed until a shared dependency arrived through one and skewed — the
failure this guard exists to prevent. Extract the rule as the exported
`isSharedSourceFile` predicate, cover all four extensions, and pin it with
regression tests (including path-boundary anchoring, so a `core-internal/`
sibling isn't swept in).
The README's `validate` row also omitted `test:scripts` and claimed typecheck
was cli/tui only; launcher runs one too, and web typechecks via `tsc -b`
inside its `build`. Restate the row to match the actual script chain.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3
Closes#1896
`clients/web`'s `tsc -b` exhausted the 4GB default heap at zod 4.4.x. The
cause is not a zod regression nor a pathological inference site of ours: it
is two copies of zod at *mismatched versions* inside one tsc program.
`clients/web/tsconfig.test.json` compiles `test-servers/src`, whose files
resolve zod (and the SDK's zod) from the **root** install, alongside web's
own sources, which resolve from `clients/web/node_modules`. At 4.3.6 vs
4.4.3 TypeScript must relate two structurally-distinct declarations of every
`@modelcontextprotocol/*` schema type, which is exponential over a recursive
generic surface — `TS2589 Type instantiation is excessively deep`, then OOM.
Bumping root zod to 4.4.3 and changing nothing else returns the build to
baseline: 11.4s and 2,567,882 instantiations, against 11.2s / 2,567,503 at
4.3.6. Two copies at the same version are harmless; skew is what explodes.
So drop the `~4.3.6` hold on `clients/web` and move all four manifests and
lockfiles to zod 4.4.3 together, and add `verify:dep-lockstep` to `validate`
to keep them there. The guard derives its candidate set from what `core/`
and `test-servers/src` import, compares the committed lockfiles' top-level
entries, and fails deny-by-default on any skew not in the annotated
`TOLERATED_SKEW` allowlist. It joins the existing mutual-vouch ring so
dropping it from `validate` is caught by `verify:format-coverage`.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HDdo1rNRVQnVRRdsqSrvG3