Summary

The look_at tool's model resolution (resolveMultimodalLookerAgentMetadata) was silently overriding the user's configured multimodal-looker model with a dynamically resolved one from the vision-capable models cache. This caused failures when the dynamically selected model (e.g., an Antigravity-prefixed Gemini model) was incompatible with the provider's API.

Problem

When a user configures multimodal-looker with a specific model (e.g., openai/gpt-5.4), the resolution function:

1. Checks if the configured model is in the vision-capable cache (populated from provider.*.models with modalities.input: ["image"])
2. If NOT in the cache (e.g., OpenAI models without explicit modality declarations), falls through to dynamic resolution
3. Dynamic resolution picks the first available vision-capable model from the cache, which may be an incompatible model
4. The configured model is silently replaced

This was confirmed via logs: the tool resolved to google/antigravity-gemini-3-pro instead of the configured openai/gpt-5.4, causing prompt failures.

Fix

• If the user explicitly configured a model for multimodal-looker, use it regardless of the vision-capable cache. The cache is incomplete (only includes models with explicit modalities.input declarations in the provider config).
• Dynamic fallback is only used when no model is registered at all.
• Removed the redundant isVisionCapableResolvedModel gate in tools.ts that would block the configured model for the same reason.

Testing

• Updated 3 existing tests to match new behavior
• All 52 look-at tests pass
• Typecheck clean
• Verified via real OpenCode session: configured GPT-5.4 is now used and returns successful responses

Summary by cubic

Ensures look_at uses the configured multimodal-looker model and variant, only falling back to dynamic resolution when none is set. Prevents silent overrides to incompatible vision models and the resulting prompt failures.

• Bug Fixes
  • Always return the registered model and variant as-is; no merging from dynamic resolution.
  • Only run dynamic resolution when no model is configured; add clear logs with the chosen path and model.
  • Remove the vision-capable gate and blocking error in tools.ts.
  • Update tests for the new behavior; all look-at tests pass.

^{Written for commit db32bad. Summary will update on new commits.}