[SSR Agent] Issue Fix (289): Document promptTokenCount and candidatesTokenCount in LLMResponse schema

[joneba-google]

fixes #289
Original issue URL: #289

Context & Problem

The hooks reference documentation listed LLMResponse.usageMetadata as containing only totalTokenCount, omitting promptTokenCount and candidatesTokenCount despite these being returned by actual model response interfaces in hooks (e.g., BeforeModel or AfterModel). This mismatch leaves integrators unaware of detailed token breakdown availability.

Detailed Changes

• Modify reference.md under docs/hooks to update the LLMResponse schema definition.
• Specifically, update the usageMetadata object within LLMResponse to document promptTokenCount and candidatesTokenCount alongside totalTokenCount.

Verification

• Inspected and verified that reference.md correctly contains the updated fields.
• Verified that the updated documentation aligns with the TS interface for HookLLMResponse/LLMResponse in hookTranslator.ts.

[github-actions]

📊 PR Size: size/XS

• Lines changed: 6
• Additions: +5
• Deletions: -1
• Files changed: 1