fix(ultrawork-model-override): fix thinking config when upgrading variant

[code-yeongyu]

Summary

• Fix ultrawork variant overrides to inject a structured thinking config object instead of copying the variant string into message.thinking.
• Keep the change targeted to ultrawork-model-override and apply the same object assignment in both variant-only and direct-mutation fallback paths.
• Update regression assertions so ultrawork now preserves thinking in enabled mode with a token budget.

Testing

• bun test src/plugin/ 2>&1
• bun run typecheck 2>&1

Fixes #2049

---

Summary by cubic

Set ultrawork message.thinking to a structured config { type: "enabled", budgetTokens: 16000 } when a variant is applied, and fix Hephaestus provider gating by correcting tests (Copilot-only should not create Hephaestus). Fixes #2049 and stabilizes a flaky CI test.

• Bug Fixes
  • Apply the thinking config in both variant-only and model-targeted override paths; update tests to assert the object shape.
  • Revert the requiresProvider change and fix the test to expect Hephaestus is absent when only github-copilot is connected; add a readConnectedProvidersCache mock to prevent state leaks.

^{Written for commit e00f461. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 2 files

Confidence score: 2/5

• There is a concrete risk of incorrect behavior: src/plugin/ultrawork-model-override.ts is missing structured thinking config on the main deferred DB path, so the DB can still be overwritten with a raw string variant.
• Given the high severity and clear impact on persisted configuration, this feels risky to merge without addressing the missing assignment/deduplication.
• Pay close attention to src/plugin/ultrawork-model-override.ts - ensure the variant/config is set in the main deferred DB path without duplicate assignments.

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/plugin/ultrawork-model-override.ts">

<violation number="1" location="src/plugin/ultrawork-model-override.ts:121">
P1: The structured thinking config is missing from the main deferred DB path, causing the DB to still be overwritten with a raw string variant. 

To fix this and eliminate the duplicated assignments:
1. Move the `variant` and `thinking` assignments to the top of the function (right after checking `if (!override)`).
2. Remove the assignments from the early return blocks.
3. Omit the `override.variant` argument from the `scheduleDeferredModelOverride` call so the DB layer doesn't overwrite the correct memory object.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P1: The structured thinking config is missing from the main deferred DB path, causing the DB to still be overwritten with a raw string variant.

To fix this and eliminate the duplicated assignments:

1. Move the variant and thinking assignments to the top of the function (right after checking if (!override)).
2. Remove the assignments from the early return blocks.
3. Omit the override.variant argument from the scheduleDeferredModelOverride call so the DB layer doesn't overwrite the correct memory object.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/plugin/ultrawork-model-override.ts, line 121:

<comment>The structured thinking config is missing from the main deferred DB path, causing the DB to still be overwritten with a raw string variant. 

To fix this and eliminate the duplicated assignments:
1. Move the `variant` and `thinking` assignments to the top of the function (right after checking `if (!override)`).
2. Remove the assignments from the early return blocks.
3. Omit the `override.variant` argument from the `scheduleDeferredModelOverride` call so the DB layer doesn't overwrite the correct memory object.</comment>

<file context>
@@ -117,7 +118,7 @@ export function applyUltraworkModelOverrideOnMessage(
     if (override.variant) {
       output.message["variant"] = override.variant
-      output.message["thinking"] = override.variant
+      output.message["thinking"] = { ...ULTRAWORK_THINKING_CONFIG }
     }
     return
</file context>

[cubic-dev-ai]

1 issue found across 1 file (changes from recent commits).

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/shared/model-requirements.ts">

<violation number="1" location="src/shared/model-requirements.ts:27">
P1: GitHub Copilot does not support `gpt-5.3-codex`. Adding it here violates codebase constraints and will break existing tests.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}