fix(model-requirements): use supported variant for gemini-3-pro

[code-yeongyu]

Summary

Fixes #1433

Changed variant: "max" to variant: "high" for gemini-3-pro fallback entries across agents and categories.

According to Google's Gemini API documentation, Gemini 3 Pro only supports "low" and "high" thinking levels:

thinkingLevel (string) - Controls the model's reasoning depth.

• Gemini 3 Pro: "low", "high" (default: "high")

Using "max" results in API errors (400 Bad Request) when the fallback resolves to Gemini 3 Pro.

Changes

Location	Type	Change
oracle	Agent	variant: "max" → variant: "high"
metis	Agent	variant: "max" → variant: "high"
momus	Agent	variant: "max" → variant: "high"
ultrabrain	Category	variant: "max" → variant: "high"
deep	Category	variant: "max" → variant: "high"
artistry	Category	variant: "max" → variant: "high"

Notes

• "high" is already the maximum thinking level supported by Gemini 3 Pro
• Other models (claude-opus-4-5 with max, gpt-5.2 with high) correctly use their respective variants
• Tests and snapshots updated to reflect the change

Related

• PR fix(model-requirements): use supported variant for gemini-3-pro #1434 attempted a similar fix from another fork

---

Summary by cubic

Fix 400 errors by switching Gemini 3 Pro fallbacks from variant "max" to "high" so thinking mode is valid. Aligns with Google’s docs and addresses #1433.

• Bug Fixes
  • Changed gemini-3-pro fallback variant to "high" for oracle, metis, and momus agents, and ultrabrain, deep, and artistry categories.
  • Updated delegate-task default artistry category to "high".
  • Updated tests and snapshots to match the new variant.

^{Written for commit 7a8a84d. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 3 files

Confidence score: 3/5

• Potential user-impacting issue: src/tools/delegate-task/constants.ts still uses variant: "max" for artistry, which likely triggers API errors after the Gemini 3 Pro variant update.
• Score reflects a concrete regression risk (severity 6/10) tied to the delegate task flow rather than a minor or speculative issue.
• Pay close attention to src/tools/delegate-task/constants.ts - update DEFAULT_CATEGORIES variant to align with the new Gemini 3 Pro requirements.

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


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

<violation number="1" location="src/shared/model-requirements.ts:34">
P2: Gemini 3 Pro variant update is incomplete.

`src/tools/delegate-task/constants.ts` still uses `variant: "max"` for the `artistry` category in `DEFAULT_CATEGORIES`. This will likely cause API errors when using the `delegate_task` tool with this category.</violation>
</file>

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

[cubic-dev-ai]

P2: Gemini 3 Pro variant update is incomplete.

src/tools/delegate-task/constants.ts still uses variant: "max" for the artistry category in DEFAULT_CATEGORIES. This will likely cause API errors when using the delegate_task tool with this category.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/shared/model-requirements.ts, line 34:

<comment>Gemini 3 Pro variant update is incomplete.

`src/tools/delegate-task/constants.ts` still uses `variant: "max"` for the `artistry` category in `DEFAULT_CATEGORIES`. This will likely cause API errors when using the `delegate_task` tool with this category.</comment>

<file context>
@@ -31,7 +31,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
     fallbackChain: [
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
-      { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "max" },
+      { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "high" },
       { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
     ],
</file context>