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Tyler Slaton 4f58ceaf00 fix(showcase/built-in-agent): make state tools strict-mode valid; bump tanstack ai (OSS-132) (#5672)
## What & why

Resolves [OSS-132](https://linear.app/copilotkit/issue/OSS-132).
Investigated with systematic-debugging; every conclusion verified
against the **real** OpenAI Responses API.

**Net change: a TanStack version bump only.** No showcase schema change.

- `@tanstack/ai` `0.18.0` → `0.35.0`
- `@tanstack/ai-openai` `0.9.1` → `0.15.6`
- `package-lock.json` regenerated (Dockerfile uses `npm ci
--legacy-peer-deps`)

## The bug

The built-in-agent showcase 400s on every prompt against real OpenAI.
The state tools (`AGUISendStateSnapshot` / `AGUISendStateDelta` /
`set_steps`) declare arbitrary payloads as `z.any()`, which serializes
to a **typeless** JSON-Schema property (`{ "description": ... }`, no
`"type"`).

The old `@tanstack/openai-base`'s `isStrictModeCompatible()` only
screened for `oneOf/allOf/not/$ref/$defs`, so it missed the missing
`type`, sent the tool with `strict: true`, and OpenAI rejected it:

```
400 Invalid schema for function 'AGUISendStateSnapshot':
In context=('properties','snapshot'), schema must have a 'type' key.
```

This was **masked in production** because the deployed showcase runs
against aimock, which replays fixtures without validating the request
schema — a raw `curl` to prod returns a clean `RUN_FINISHED`, green for
the wrong reason.

The ticket's original framing (zod3/zod4 drift → typeless *root*, `got
"None"`) was already fixed by the zod-4 migration; this is the same
symptom one layer down (typeless *property*).

## The fix is upstream

`@tanstack/ai-openai@0.15.6` (via `@tanstack/openai-base@0.9.2`) fixes
`isStrictModeCompatible`: it now detects typeless / `z.any()` properties
and sends `strict: false`. OpenAI accepts typeless properties under
`strict: false` — so `z.any()` works again with no schema change on our
side.

(`@tanstack/ai-openai@0.15.5` also dropped `@tanstack/ai-client` from
its peerDependencies, so no `ai-client` dep is added.)

## Verification (real OpenAI, gpt-4o)

| Probe | Result |
|---|---|
| Typeless property, `strict: true` (raw OpenAI) | **400** — `schema
must have a 'type' key` |
| Typeless property, `strict: false` (raw OpenAI) | **ACCEPTED** —
confirms it was the strict flag, not the schema |
| `z.any()` tool on old adapter (0.9.1/0.15.4) | adapter sends `strict:
true` → **400** |
| `z.any()` tool on new adapter (0.15.6) | adapter sends **`strict:
false`** → **ACCEPTED**, model calls the tool |
| All 3 `z.any()` state tools attached, new adapter | **ACCEPTED**, no
400 |

## Not covered here

The showcase's aimock + Playwright e2e suite was **not** run locally
(this worktree has no installed toolchain). CI runs it on this PR;
please confirm the gen-ui / shared-state demos still pass before merge.

---
_Branch history shows an interim `z.string()` workaround that was
reverted once the upstream fix shipped; the net diff is the version bump
only. Squash-merge recommended._
2026-07-06 13:59:32 -07:00
..