Diff Viewer for Prompt, Config, and Output Comparisons

Compare two versions of text, prompts, configs, or generated output so you can see exactly what changed and why it matters.

Quick orientation

When to use this tool

Use the diff viewer when the new version feels different but you need to know whether it is actually better, safer, or just changed in noisy ways.

1
When reviewing prompt edits or policy changes
2
When comparing generated outputs after a model or config change
3
When debugging why a small edit had a big downstream effect

Original (A)

Modified (B)

+8 added-1 removed13 unchanged

 # AGENTS.md - Rules
 
 ## Memory System
 - Daily notes in memory/YYYY-MM-DD.md
 - Synthesized preferences in MEMORY.md
+- Read WRITING-STYLE.md before creating content
 
 ## Writing Rules
 - No em dashes
-- Avoid obvious AI words
+- Avoid obvious AI words and inflated phrasing
 - Prefer simple wording
+- Vary sentence length
 
 ## Security
 - Never send raw credentials
 - Financial data is confidential
+- PII must be redacted before sending
+
+## Data Classification
+- Internal: OK in group chats
+- Confidential: private chat only

Why diffs help agent work

Agent systems are sensitive to small wording and config changes. A clean diff makes those shifts visible before you rely on memory or guesswork.

Review prompt changes without rereading whole files from scratch
Spot accidental config drift quickly
Share exact before-and-after changes during debugging

Read the change well

What a useful diff review should answer

The point is not just spotting differences. It is understanding whether the change improved clarity, safety, or behavior.

A tiny prompt or config change can have a bigger effect than a long rewrite. Diffs help you catch that before you trust your memory.

If a result changed unexpectedly, review deletions first. Missing context often explains more than added text.

Use a diff before blaming the model. Sometimes the real cause is one instruction that quietly moved or disappeared.

When collaborating, sharing the exact before-and-after is usually faster than paraphrasing what changed.

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Learn next

Turn the estimate into a better setup

If the tool solved the immediate question, this is the next place to go for the broader workflow, tradeoffs, and implementation detail.

Review common mistakes before they compound

FAQ

Why compare prompts with a diff instead of just rereading them?

Because small wording changes are easy to miss in full text, especially when the prompt is long or multiple people have edited it.