haystack

No clear indicators of intentional malware (e.g., credential theft, backdoors, persistence, or malicious network destinations) are present in the shown fragment. However, the code includes a security-critical anti-pattern: a calculator tool that uses `eval()` on an `expression` string that can be influenced by user/agent behavior. Combined with tool-calling orchestration and unvalidated prompt inputs (retrieved `doc.content`), this creates a meaningful security risk. Replace `eval()` with a safe arithmetic parser/allowlist (e.g., parse numbers/operators only) and sanitize/limit retrieved content used in prompts as appropriate.