Same image, different purpose: draft appropriate alt text

Draft alt text from a supplied image description and page purpose without inventing identity or emotion. Officially documented feature · Workflow untested

Execution environment and usage

AI / software

Gemini

Where to operate

Ordinary Gemini web text chat

Getting started

  1. Use authorized de-identified short text, choose your own parameters and keep the original.
  2. Paste the prompt and fixture into ordinary Gemini web text chat without connecting services.

Setup and plan requirements

Prefer an adult personal account. Official web lists include Hong Kong, Macau, Taiwan and Traditional Chinese. Local connections were not tested.

Prompt portability limits

Standard limits exist without a paid plan. Usage caps vary; local paid prices are unverified. No specific model or prompt count is guaranteed.

Usage limitations

Mobile/API/CLI are outside this check. No accounts are read, devices controlled, messages sent or purchases made. Do not supply secrets; activity-off chats may remain for 72 hours and receive safety processing.

Environment sources

適用情境 / When to use

Draft alt text from a supplied image description and page purpose without inventing identity or emotion. Fictional fixture: description is a bar chart with A 10 and B 15, units items. Purpose A compares quantities. Purpose B is decorative beside equivalent complete data.

步驟 / Steps

  1. Use authorized de-identified short text, choose your own parameters and keep the original.
  2. Paste the prompt and fixture into ordinary Gemini web text chat without connecting services.
  3. Human check: A retains A 10 items and B 15 items, without inventing sales or growth. B may suggest reviewing empty alt, but a person must inspect the actual page.
  4. Check against the human answer and source. Preserve errors; never present an expected answer as observed output.

提示詞 / Prompt

Draft alt text in [language] using only [human image description] and [page purpose]. State that you have not seen the image. Retain essential information for informative images; for purely decorative use, suggest human review of empty alt text, not automatic application. Do not infer identity, emotions or undescribed details. Ask when purpose is unclear.

Fictional fixture: description is a bar chart with A 10 and B 15, units items. Purpose A compares quantities. Purpose B is decorative beside equivalent complete data.

留意事項 / Cautions

  • Prefer an adult personal account. Official web lists include Hong Kong, Macau, Taiwan and Traditional Chinese. Local connections were not tested.
  • Standard limits exist without a paid plan. Usage caps vary; local paid prices are unverified. No specific model or prompt count is guaranteed.
  • Mobile/API/CLI are outside this check. No accounts are read, devices controlled, messages sent or purchases made. Do not supply secrets; activity-off chats may remain for 72 hours and receive safety processing.
  • Alt-text guidance: W3C image decision tree https://www.w3.org/WAI/tutorials/images/decision-tree/
  • Functional images need their action or purpose described; complex charts need complete text or data separately. Empty alt is not an omitted alt attribute.

來源限制 / Evidence limits

Original text-only exercise with fictional examples, not observed user outcomes. Official documentation supports text prompting, not the effectiveness of this exercise. Document publication date unspecified; checked 2026-11-13.

流程說明 / Workflow note

Original text-only exercise with fictional examples, not observed user outcomes. Official documentation supports text prompting, not the effectiveness of this exercise.

Source checked: 2026-11-13

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