- Implemented in-house, zero-dependency utility modules in `pi-utils` covering DOM manipulation, markdown parsing, templating, browser automation helpers, and terminal buffers.
- Migrated packages across the repository to consume the new internal utilities and `omptype` schema validators instead of external dependencies.
- Removed multiple external runtime and development dependencies including Zod, Marked, LRU cache, Turndown, and Puppeteer browser packages.
- Added native support for parsing, normalized validation, and serialization of ArkType schemas throughout the agent pipeline.
- Implemented pruning of unconstrained union branches and normalization helpers to handle unrepresentable strict-mode branches.
- Patched ArkType's schema package to preserve declared object key order during serialization.
- Integrated ArkType schemas into `agent-loop` and migrated coding agent tool parameters to ArkType format.
- Tracked whether strict tool schemas were actually applied and used that flag when deciding strict-to-nonstrict retries.
- Recorded strict-tool failures in session state so later requests skip strict mode retries and avoid extra error rounds.
- Hardened strict schema normalization by flattening nested pure anyOf unions and expanded schema error matching for additional invalid-schema rejections.
Only flatten optional anyOf schemas when the union wrapper has no sibling constraints that would exclude null.
Added a strict-schema regression for constrained anyOf properties so null remains an outer branch.
Flattened optional union tool schemas during strict enforcement so OpenRouter DeepSeek V4 no longer receives nested anyOf branches without a type.
Added schema-level and OpenRouter DeepSeek payload regressions for optional string-or-array tool parameters.
Fixes#2270
- Extracted `description` from type-array and nullable branches so it lives on the wrapper, not duplicated onto each variant.
- Replaced inline enum-type inference with `inferStrictPrimitiveTypeFromEnumOrConst`, covering both `enum` and `const` in sanitize and enforce paths.
- Mixed-primitive enums and non-primitive consts now fall back to non-strict instead of producing a typeless schema that OpenAI rejects on the wire.
- Added strict-mode ref preprocessing to resolve local `#/` refs with sibling-key precedence.
- Added single-item allOf handling that inlines the sole schema entry and retains multi-item allOf.
- Added Anthropic schema normalization to retain whitelisted metadata and enforce stricter key handling.
- Added Google schema sanitizer options for snake_case renaming, null-collapse behavior, and ordering.
- Expanded schema tests for Anthropic, Google, and strict-mode parity across refs, arrays, and recursion.
- Adopted draft-2020-12 tuple validation with `prefixItems`, rejecting array-valued `items`.
- Expanded strict-mode handling to recurse `prefixItems` entries and infer `array` when tuple prefixes exist.
- Normalized Anthropic schemas through `prefixItems`, keeping supported tuple constraints and dropping unsupported fields.
- Updated coding-agent schema metadata and tests to draft-2020-12 `$schema` targets, including MCP/theme fixtures.
- Added `trimTrailingWhitespace()` to strip trailing spaces/tabs and keep the original line when none exist.
Primitive $ref recursion now emits a validation issue when the depth cap is exceeded instead of returning true. This preserves termination without accepting invalid values at the end of a long ref chain.
- JSON Schema validator now enforces propertyNames, patternProperties, dependentRequired, dependencies, if/then/else, contains, and prefixItems instead of silently accepting values that violate them; unevaluated* still permissive but warns once.
- Recursive $ref no longer short-circuits to true on revisit: cycle detection keys on (ref, value-identity) with a primitive depth cap, so nested sub-schema violations are caught.
- Meta-validator now structurally validates if/then/else/dependencies sub-schemas and accepts draft-07 dependencies as either schemas or string-array dependent keys.
- Wire-schema null normalization no longer strips null-valued unknown root fields before preserveUnknownRootFields snapshots them, so task.simple and similar callers still see disallowed null arguments.
- Added canonical `pi.zod` schema API exports and removed TypeBox package exports/imports.
- Migrated Tool schema typing from TypeBox to shared `TSchema`/Zod flow with legacy TypeBox compatibility.
- Updated AI provider adapters and MCP/agent builders to convert tool params through `toolWireSchema()`.
- Reworked schema validation from AJV to Zod-safe parsing with `fromTypeBox`, `toolWireSchema`, and meta schema checks.
- Added `toolStrictMode` support with `all_strict`/`none`/`mixed` options to OpenAI compatibility.
- Fixed OpenAI-completion strict-mode flows by capturing failed HTTP responses and retrying once as non-strict.
- Fixed completion error reporting by surfacing captured status, headers, and JSON `type`/`param`/`code` details.
- Improved strict-schema enforcement with WeakMap memoization and circular-schema detection in sanitization.
- Fixed OpenRouter provider lookup by resolving fallback model IDs for suffix and date variants in registry resolution.
- Refactored benchmark tooling and added async RPC error-window tracking for scheduled run execution.
## New: schema compatibility validation API
Add `validateSchemaCompatibility(schema, provider)` in
`packages/ai/src/utils/schema/compatibility.ts` that performs a static
audit of a JSON Schema against three provider targets:
- `openai-strict`: checks forbidden keys, required/properties symmetry,
additionalProperties constraint, and that every node declares a type,
combinator, or $ref
- `google`: checks unsupported keyword set and array-valued type
- `cloud-code-assist-claude`: checks forbidden keywords, array type,
null type, nullable keyword, and combiner presence; also validates via
AJV 2020 draft
Add `validateStrictSchemaEnforcement(original, result)` to assert the
fail-open contract: when strict enforcement succeeds the output must pass
openai-strict validation; when it fails the output must be the original
schema object (same reference).
Export both functions and their types from `./utils/schema/index.ts`.
## New: shared constants in fields.ts
Extract `COMBINATOR_KEYS` (`anyOf`, `allOf`, `oneOf`) and add
`CCA_UNSUPPORTED_SCHEMA_FIELDS` as exported constants, eliminating the
local duplicate in `strict-mode.ts` and providing a canonical field set
for Cloud Code Assist (much narrower than the Google set — CCA supports
validation keywords like `additionalProperties`, `minLength`,
`pattern`, etc.).
## Fix: cycle detection in all recursive schema traversals
All recursive walkers now carry a `WeakSet<object>` guard. Previously any
schema with a reference cycle (or a schema object that appears at two
nodes in the tree) would cause an infinite loop or a stack overflow:
- `sanitizeSchemaForStrictMode` / `enforceStrictSchema`
- `normalizeSchemaForCloudCodeAssistClaude`
- `normalizeNullablePropertiesForCloudCodeAssist`
- `stripResidualCombiners`
- `sanitizeSchemaImpl` (Google sanitizer)
- `hasResidualCloudCodeAssistIncompatibilities`
`hasResidualCloudCodeAssistIncompatibilities` previously returned `true`
for already-visited nodes, producing false positives that forced the CCA
fallback schema on valid (but multiply-referenced) schemas. It now
correctly returns `false`.
## Fix: stripResidualCombiners iterates to fixpoint
The previous single-pass approach missed chained combiner reductions
where one collapsed variant exposed another reducible combiner. The
rewriter now loops until no further reduction occurs.
## Fix: mergeObjectCombinerVariants required-field computation
The merged object schema now takes the intersection of all variants'
`required` arrays, then unions in own-level required properties that
exist in the merged schema. Previously the `required` field was silently
dropped from the flattened schema, making all properties effectively
optional.
## Fix: sanitizeSchemaForGoogle improvements
- Type inference for const-collapsed enums: type is derived from all
variants (must unanimously agree), falling back to inference from enum
values; mixed null/non-null infers the non-null scalar type and sets
`nullable: true`
- Const→enum deduplication now uses deep structural equality instead of
`Object.is`
- Recursion spreads the full options object so new fields (`unsupportedFields`,
`seen`) are not silently dropped when descending into sub-schemas
- Array-valued `type` is filtered to strings before processing
- Removed incorrect stripping of `additionalProperties: false` (the
field is valid and should be preserved)
- Parameterized `unsupportedFields` in `SanitizeSchemaOptions` enables
code reuse between the Google and CCA sanitizers
## Fix: sanitizeSchemaForStrictMode / enforceStrictSchema
- `nullable: true` is now stripped during sanitization and expanded into
`anyOf: [schema, {type: "null"}]` in the enforcer output, matching
what OpenAI strict mode requires
- Type inference: `type: "array"` is inferred when `items` is present;
a scalar type is inferred from uniform `enum` values
- Const→enum merge uses deep equality to avoid duplicate entries when
both `const` and `enum` exist with the same value
- `additionalProperties` is now dropped unconditionally in sanitization
(previously only object-valued `additionalProperties` was recursed;
non-object values were passed through)
- `enforceStrictSchema` recurses into `$defs` and `definitions` blocks
- `enforceStrictSchema` handles tuple-style `items` arrays
- `enforceStrictSchema` skips double-wrapping: optional properties
already expressed as `anyOf: [..., {type: "null"}]` are not wrapped again
- `tryEnforceStrictSchema` now caches results in a `WeakMap` keyed on
the input schema object to avoid redundant work on repeated calls
## Fix: mergeCompatibleEnumSchemas deep equality
Uses `areJsonValuesEqual` instead of `Object.is` when deduplicating
enum members, so structurally equal objects are not duplicated.
## New: test coverage
- `packages/ai/test/schema-normalization.test.ts`: comprehensive unit
tests for strict mode, Google, and Cloud Code Assist normalization
- `packages/ai/test/schema-compatibility.test.ts`: unit tests for all
three provider targets in the new compatibility validator
- `packages/coding-agent/test/tools/provider-schema-compatibility.test.ts`:
integration test that instantiates every builtin and hidden tool, runs
their parameter schemas through all three provider pipelines, and
asserts zero compatibility violations
- Extracted schema utilities from typebox-helpers and google-shared into new modular utils/schema package with 17 exported functions.
- Consolidated OpenAI strict mode schema enforcement across codex, completions, and responses providers using unified adaptSchemaForStrict() helper.
- Refactored credential ranking from hardcoded Codex-specific logic to pluggable CredentialRankingStrategy pattern with provider implementations.
- Migrated 500+ lines of Google schema sanitization and normalization logic from google-shared.ts to dedicated utils/schema modules with expanded functionality.
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