Compare Two Documents and Summarize the Differences

    Compare the two documents below and tell me what's different.

Document A:
{{doc_a}}

Document B:
{{doc_b}}

What I care about (optional — e.g. what changed in terms, scope, numbers, meaning): {{focus}}

Please:
- Summarize the **substantive differences** — what was added, removed, or changed in meaning — organized by section or theme.
- Distinguish **material changes** (that affect meaning, terms, obligations, or numbers) from minor wording or formatting tweaks.
- Where a change matters, note its **implication** — what it actually changes in practice.
- Flag anything that looks like it changed but is ambiguous, so I can look closer.

Compare only what's in the two documents; don't infer intent behind a change beyond what the text supports, and don't invent differences. If the documents are long, lead with the most important changes. If one seems truncated or they're not really comparable, say so.