v1.6.3 — Unblock Claude Code (draft 2020-12 tuple fix)

1.6.3 (2026-04-21)

Patch: unblock Claude Code after the 1.6.2 Gemini fix. 1.6.2's sanitizer
stripped $schema (intentional, for Gemini) without also normalizing the
draft-07 tuple syntax (items: [schemaA, schemaB]) that two tools emit
via z.tuple([...]). Without the $schema annotation, Claude's API
validator falls back to JSON Schema 2020-12, where items: [array] is
invalid — causing tools.N.custom.input_schema: JSON schema is invalid
errors on any session that loaded the ShapeItUp tool catalog.

Fixed

• Sanitizer now rewrites draft-07 tuple items to uniform-array form:
  { items: <shared schema>, minItems: N, maxItems: N } for homogeneous
  tuples, { minItems: N, maxItems: N } for heterogeneous ones. Valid
  under both JSON Schema 2020-12 (Claude) AND OpenAPI 3.0 (Gemini).
• Affected tools: check_collisions.acceptedPairs, verify_shape. collisionAcceptedPairs (both z.array(z.tuple([z.string(), z.string()]))).
• Regression gate added: the tools/list integration test now asserts zero
  tuples remain in the emitted catalog on every CI run.

Users on 1.6.2 should upgrade — that version broke Claude Code.

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URGENT upgrade from 1.6.2. The Gemini-compat sanitizer in 1.6.2 accidentally broke Claude Code by stripping $schema without normalizing draft-07 tuple syntax — Claude falls back to draft 2020-12 where items: [array] is invalid. 1.6.3 fixes both clients.