Good Prompts Are Not Enough:
How to Verify and Trace AI Answers
Many people use AI as a search engine, tutor, or advisor. But AI output often mixes facts, plausible guesses, and fabricated details. What matters is not only how to ask, but how to verify what comes back. This chapter connects source tracing, lateral reading, reverse search, and citation habits into one AI-era workflow.
Context Manipulation: The Most Overlooked Technique
First Draft (a Harvard research project), after analyzing thousands of disinformation cases, categorized visual content misinformation into seven types. The most common isn't "completely fabricated content" but "False Context" — using real images or videos but pairing them with false time, location, or event descriptions.
Why is context manipulation so effective? Because:
- Real images/videos pass the first "looks real" visual check
- Most people's verification habit is "check if the image was modified," not "check the image's original source"
- Reverse image search remains a skill mastered by few; most ordinary users have never used it
| Type | Description | Frequency |
|---|---|---|
| False Context | Real content + false context | ★★★★★ |
| Imposter Content | Impersonating credible sources | ★★★★☆ |
| Manipulated Content | Real images modified | ★★★☆☆ |
| Fabricated Content | Entirely fabricated content | ★★☆☆☆ |
Reverse Image Search: Three Free Tools
Reverse image search is the most effective image tracing tool. The principle: use the image itself as a search key to find all locations where the image has appeared online, thereby confirming when and where it first appeared.
| Tool | Strength | Weakness | Best For |
|---|---|---|---|
| Google Images | Easy entry point, integrated with Chrome / Google Lens | Does not always reveal the earliest source | Everyday news images, product images, landmark clues |
| TinEye | Precisely tracks first appearance date | Relatively smaller database | Confirming an image's "age" |
| Yandex Images | Useful as a cross-check beyond Google / TinEye | Interface and ranking require extra interpretation | Comparing results across search engines |
Step-by-Step (Using Google)
- In Chrome browser, right-click any image → select "Search image with Google," or go to images.google.com and click the camera icon
- Upload the image file or paste the image URL
- Check the "Visually similar images" and "Other sizes of this image" sections in the results
- Compare the earliest reporting date in the results to confirm if the image first appeared before the claimed event date
Video Tracing: How to Use InVID
Videos can't be directly reverse-searched, but the InVID/WeVerify browser extension greatly simplifies this process:
- Install Chrome/Firefox extension (search "InVID WeVerify")
- Use the "Video analysis" function on video links from YouTube, Facebook, Twitter, etc. — automatically captures 16 key frames and runs reverse image search
- Check search results for each key frame to confirm if the video appeared in other contexts before
Geolocation Verification: Using SunCalc and Google Earth
When a video claims to be filmed in a certain location but you suspect the location is wrong, use:
- Google Street View: Screenshot buildings, street signs, and storefronts from the video, then search for possible matches in Street View. Public Bellingcat / CIR cases show that reliable geolocation usually requires cross-checking landmarks, timelines, satellite imagery, and other open-source evidence.
- SunCalc.org: Enter the claimed location and date on SunCalc to calculate the sun's azimuth and elevation at any time of day. Compare with shadow directions in the video to verify whether the "date + location" combination is consistent.
- Google Earth Timelapse: View historical satellite imagery of a location to confirm timelines of construction and landscape changes, ruling out the possibility that "this was filmed years ago."
EXIF Metadata: The Invisible Diary of Photos
Every digital photo contains hidden EXIF (Exchangeable Image File Format) metadata: capture time (accurate to the second), camera model, lens information, and in cases where it hasn't been stripped, GPS coordinates.
Important caveats:
- Social media platforms like Facebook and Instagram usually strip GPS data on upload, but don't necessarily strip capture time
- EXIF data can be modified, making it "supporting evidence" rather than "final proof"
- Use Jeffrey's EXIF Viewer (jeffreyfriendship.com) or exiftool to read EXIF data
Lateral Reading: Stanford University's Breakthrough Research
Stanford University's History Education Group (SHEG) conducted an important experiment: they had three groups — high school students, college students, and professional fact-checkers — evaluate the same suspicious websites. The results were surprising: professional fact-checkers had 3× higher accuracy than the other two groups.
What exactly did they do differently? The researchers recorded the professional fact-checkers' screen actions and found one critical difference:
- Ordinary people (vertical reading): Carefully read the suspicious website's articles, trying to judge credibility from the site's own "About Us" page
- Professional fact-checkers (lateral reading): After seeing the suspicious site's headline, immediately opened new tabs in the search engine to search "what is this website's background," finding others' evaluations of this source
When you encounter an unfamiliar source, don't read the article first. Instead:
- Open a new tab, search "[site name] + credibility / bias / fake news"
- Search "[site name] + site:en.wikipedia.org" to see if Wikipedia describes this source
- Check Media Bias / Fact Check (mediabiasfactcheck.com) ratings
- Spend just 60-90 seconds for a basic credibility assessment of the source
Taiwan Fact-Checking Resource Map
For Taiwan users, these are the most practical Chinese-language verification resources:
台灣最大事實查核機構，LINE 機器人可即時查詢。
tfcctw.org
在 LINE 中加入好友，直接傳送可疑訊息即可查詢。
mygopen.com
社群協作查核 LINE 群組流傳的假訊息。
cofacts.tw
專注台灣政治相關假訊息的獨立查核媒體。
rumtoast.com
Slide Deck
Case Studies
After the April 3, 2024 Hualien magnitude 7.2 earthquake, many disaster images and clips circulated on social platforms. Some were genuine, while others reused old footage or placed real footage in the wrong location or context. In the first hours after a disaster, people urgently seek safety information, making these visuals especially easy to reshare.
Taiwan FactCheck Center compiled earthquake-related visual checks, and AFP Fact Check documented several misleading posts that reused old photos, demolition clips, or unrelated footage as if they were live Taiwan earthquake scenes.
A practical workflow is to extract key frames, run reverse image search, compare earliest appearance dates, and check location clues against reliable reporting. If an image predates April 3, 2024 or the location does not match the claimed earthquake scene, it should not be labeled as live disaster footage.
Emergency disaster periods are peak times for misleading visuals. Reverse image search is a strong first step, but it should be combined with time, location, uploader, and credible-media checks.
In the early days of Russia's invasion of Ukraine, social platforms carried many old videos, game clips, and war images stripped from their original context. Fact-checkers confirmed that one widely shared "Ghost of Kyiv" air-combat clip was created in Digital Combat Simulator, not recorded from a real Ukrainian Air Force engagement.
A practical workflow is: ① extract key frames for reverse image search ② compare landmarks, roads, buildings, and street views ③ look for independent reporting on the same event ④ trace the earliest recoverable upload. These steps help separate real battlefield documentation from recycled footage and game simulations.
When wars and major conflicts break out, disinformation creators know news consumption spikes — making it the optimal moment to release fake footage. Reverse search + geolocation matching + timeline analysis is the golden combination for distinguishing real battlefield documentation from disinformation.
- For "disaster," "battlefield," "accident scene" images, do reverse search before sharing
- Use TinEye "Sort by Oldest" to confirm an image's "age"
- When unsure, wait for Taiwan FactCheck Center or Reuters Fact Check reports