Single tool with minimal definition quality. Tool name 'append_streaming_token' lacks action clarity (append vs add?). Description is 82 chars but lacks WHEN/WHY context for LLM selection. Input schema present but parameters lack descriptions entirely, 'token_id' and 'text' have no guidance on format, constraints, or purpose. No output schema documented. No error handling guidance. No parameter validation rules stated. Fails multiple critical checks from rubric section B (descriptions) and C (parameters).

• Add parameter descriptions: 'token_id (integer): Unique sequential identifier for this token in the stream (e.g., 0, 1, 2, ...). Used to track eviction order.' and 'text (string): The token text content (1-512 chars). Used for cache statistics and debugging.'
• Document output schema in tool description: 'Returns {total_tokens_streamed: int, active_cache_tokens: int, max_cache_capacity: int, tokens_evicted: int, compression_ratio: float}.'
• Expand tool description to 150-200 chars: 'Appends a token to a streaming KV cache with attention sink preservation. Retains initial sink tokens (e.g., system prompt) and applies sliding-window FIFO eviction to recent tokens. Call this for each token in a streaming LLM response to manage GPU memory under fixed budget.'
• Add parameter constraints: token_id must be non-negative integer; text must be non-empty string. Document in descriptions.
• Add error handling: Return structured errors like '{error: "duplicate_token_id", message: "Token ID 42 already exists", recovery: "Use next sequential ID"}' instead of silent failures.