How do the FLUX, Imagen, Gemini and OpenAI docs tell me to write text I want rendered in an image (quoting, length, font description), and what limits do they admit?
Corrected 2026-10-24 - see C3-B955-06; the original statements below are kept for history and are superseded where the correction says so. Problem. Generated posters, logos and title cards need correct words; vendors give different rules. Conditions. Vendor docs fetched 23 Oct 2026; model names change quickly. Method (documented). FLUX 3 Image (BFL): for each text block quote the exact words with the capitalisation and punctuation wanted, say where it sits in the frame, and describe the type (weight, case, colour, character, e.g. a clean sans-serif black font); a word or short line needs no layout, just a quoted string and a place. Imagen on Vertex AI (Imagen 3 guidance): keep text to 25 characters or less, use at most two or three distinct phrases, expect placement variations, name a general font style but do not expect precise font replication, give a size word (small, medium, large), and regenerate until it works. Gemini image docs: be clear about the text, the font style (descri...
Problem. Generated posters, logos and title cards need correct words; vendors give different rules. Conditions. Vendor docs fetched 23 Oct 2026; model names change quickly. Method (documented). FLUX 3 Image (BFL): for each text block quote the exact words with the capitalisation and punctuation wanted, say where it sits in the frame, and describe the type (weight, case, colour, character, e.g. a clean sans-serif black font); a word or short line needs no layout, just a quoted string and a place. Imagen on Vertex AI (Imagen 3 guidance): keep text to 25 characters or less, use at most two or three distinct phrases, expect placement variations, name a general font style but do not expect precise font replication, give a size word (small, medium, large), and regenerate until it works. Gemini image docs: be clear about the text, the font style (descriptively) and the overall design, with a template of the form Create a [image type] for [brand/concept] with the text "[text to render]" in a [font style]; they recommend the Pro image model for professional asset production. The Gemini infographic example then edits the same graphic into Spanish with a follow-up turn, so localisation is done by editing rather than regenerating. OpenAI's GPT Image guide lists text rendering among limitations: improved, but the model can still struggle with precise text placement and clarity. Defaults to adopt [inference]: quote every string, keep each phrase short (25 characters is the only numeric limit I found, and it is Imagen-specific), cap a graphic at about three text blocks, specify typeface character not a font name, and always proofread output letter by letter. Failure modes. Misspellings, dropped letters, wrong placement and substituted fonts; the docs do not give error rates. Limitations. Different vendors, different model generations; no cross-vendor test was run. Version/date. 2026-10-23.
Curator correction 2026-10-24 (discovery audit record C3-B955-06; sources re-fetched 2026-10-24, excerpts re-located by curator GET): Source refresh of C3-B593-01 (checked 2026-10-24). The finding's Imagen rules (25 characters, three phrases, no precise font replication) come from the Vertex AI Imagen 3 prompt guide, which still contains them. But the model lifecycle has changed: the Vertex model-versions page lists imagen-3.0-generate-002 and imagen-4.0-generate-001 under 'Retired models' with retirement date June 30, 2026 (upgrade: gemini-2.5-flash-image). The Gemini API deprecations page lists imagen-4.0-generate-001 shutdown 'August 17, 2026' with replacement gemini-nano-banana-2.1, and imagen-3.0-generate-002 'November 10, 2025'. The Gemini API models page lists 'Imagen 4 (Shut down)'. The Vertex prompt-guide page itself says 'Vertex AI documentation is no longer being updated'. So the Imagen guidance is historical; for a live pipeline use the Gemini image docs (Nano Banana models) and treat the 25-character figure as unverified for those models. The Gemini image text advice in the finding remains present on the current page. OpenAI part of C3-B593-01 not re-checked here.
Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources.
Limitations: Only Imagen gives numeric limits and its guidance is for Imagen 3; whether newer Google models keep the 25-character advice is not stated. Claims of improved text rendering are vendor statements.
Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
"citations": [
{
"url": "https://docs.bfl.ml/guides/prompting_unified_style.md",
"note": "Text in Images; Short text in a plain prompt; Generate text in images; Generate text in images; Generate text in images; Accurate text in images; infographic example; Limitations; Limitations"
},
{
"url": "https://docs.cloud.google.com/vertex-ai/generative-ai/docs/image/img-gen-prompt-guide",
"note": "Text in Images; Short text in a plain prompt; Generate text in images; Generate text in images; Generate text in images; Accurate text in images; infographic example; Limitations; Limitations"
},
{
"url": "https://ai.google.dev/gemini-api/docs/image-generation.md.txt",
"note": "Text in Images; Short text in a plain prompt; Generate text in images; Generate text in images; Generate text in images; Accurate text in images; infographic example; Limitations; Limitations"
},
{
"url": "https://developers.openai.com/api/docs/guides/image-generation.md",
"note": "Text in Images; Short text in a plain prompt; Generate text in images; Generate text in images; Generate text in images; Accurate text in images; infographic example; Limitations; Limitations"
}
]
}Evidence claims
- [sourced_fact] Curator correction 2026-10-24 (discovery audit record C3-B955-06; sources re-fetched 2026-10-24, excerpts re-located by curator GET): Source refresh of C3-B593-01 (checked 2026-10-24). The finding's Imagen rules (25 characters, three phrases, no precise font replication) come from the Vertex AI Imagen 3 prompt guide, which still contains them. But the model lifecycle has changed: the Vertex model-versions page lists imagen-3.0-generate-002 and imagen-4.0-generate-001 under 'Retired models' with retirement date June 30, 2026 (upgrade: gemini-2.5-flash-image). The Gemini API deprecations page lists imagen-4.0-generate-001 shutdown 'August 17, 2026' with replacement gemini-nano-banana-2.1, and imagen-3.0-generate-002 'November 10, 2025'. The Gemini API models page lists 'Imagen 4 (Shut down)'. The Vertex prompt-guide page itself says 'Vertex AI documentation is no longer being updated'. So the Imagen guidance is historical; for a live pipeline use the Gemini image docs (Nano Banana models) and treat the 25-character figure as unverified for those models. The Gemini image text advice in the finding remains present on the current page. OpenAI part of C3-B593-01 not re-checked here. · locator: curator correction paragraph in this record body (C3-B955-06) source
- [sourced_fact] SUPERSEDED IN PART 2026-10-24 by curator correction C3-B955-06 (see the correction claim above); original kept for history: Problem. Generated posters, logos and title cards need correct words; vendors give different rules. Conditions. Vendor docs fetched 23 Oct 2026; model names change quickly. Method (documented). FLUX 3 Image (BFL): for each text block quote the exact words with the capitalisation and punctuation wanted, say where it sits in the frame, and describe the type (weight, case, colour, character, e.g. a clean sans-serif black font); a word or short line needs no layout, just a quoted string and a place. Imagen on Vertex AI (Imagen 3 guidance): keep text to 25 characters or less, use at most two or three distinct phrases, expect placement variations, name a general font style but do not expect precise font replication, give a size word (small, medium, large), and regenerate until it works. Gemini image docs: be clear about the text, the font style (descriptively) and the overall design, with a template of the form Create a [image type] for [brand/concept] with the text "[text to render]" in a [font style]; they recommend the Pro image model for professional asset production. The Gemini infographic example then edits the same graphic into Spanish with a follow-up turn, so localisation is done by editing rather than regenerating. OpenAI's GPT Image guide lists text rendering among limitations: improved, but the model can still struggle with precise text placement and clarity. Defaults to adopt [inference]: quote every string, keep each phrase short (25 characters is the only numeric limit I found, and it is Imagen-specific), cap a graphic at about three text blocks, specify typeface character not a font name, and always proofread output letter by letter. Failure modes. Misspellings, dropped letters, wrong placement and substituted fonts; the docs do not give error rates. Limitations. Different vendors, different model generations; no cross-vendor test was run. Version/date. 2026-10-23. · locator: Text in Images; Short text in a plain prompt; Generate text in images; Generate text in images; Generate text in images; Accurate text in images; infographic example; Limitations; Limitations source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |