Support 1M token context for GPT-5.5 in Codex
### What variant of Codex are you using? latest ### What feature would you like to see? I want to give feedback on the current GPT-5.5 context limit in Codex. From the official announcement, I understand that GPT-5.5 in Codex is documented as having a 400K context window, while the API version supports 1M context. So this does not look like an undocumented bug. My concern is with the product decision itself. With GPT-5.4, Codex users could configure a much larger context window through `model_context_window`. For example: ```toml model = "gpt-5.4" model_context_window = 1000000 model_auto_compact_token_limit = 512000 ``` That made GPT-5.4 very useful for large repositories and long-running coding sessions. But with GPT-5.5, even though the model itself is supposed to be better at long-context reasoning and large coding tasks, Codex subscription users are now capped at 400K context. In practice, that makes GPT-5.5 feel like an upgrade in model quality but a downgrade in long-context usability inside Codex. I understand that 1M context is expensive. I also understand why 400K might be a reasonable default for most users. But I do not think it should be the hard limit for everyone. For advanced Codex users, especially those working on large codebases, the choice between compaction and full context matters a lot. Codex compaction is good, but it is still a tradeoff. During complex debugging, architecture analysis, or multi-file refactors, I would often rather spend mo
Posted by umikato on Apr 24, 2026, 11:26 PM
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In the UK Amazon have now raised the price of general shipping to be 2/3 the price of a months prime subscription.
Credit where credit is due, critics claiming "[Apple device] is too expensive for something that just does [basic function]" have been pr...
I like to buy music.
Meet K-Claw.
Fable is way too expensive for basic software stuff.
[Meta] Abnormal Codex usage/quota depletion and usage-accounting inconsistencies — cross-report tracker
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Support 1M token context for GPT-5.5 in Codex
### What variant of Codex are you using? latest ### What feature would you like to see? I want to give feedback on the current GPT-5.5 context limit in Codex. From the official announcement, I understand that GPT-5.5 in Codex is documented as having a 400K context window, while the API version supports 1M context. So this does not look like an undocumented bug. My concern is with the product decision itself. With GPT-5.4, Codex users could configure a much larger context window through `model_context_window`. For example: ```toml model = "gpt-5.4" model_context_window = 1000000 model_auto_compact_token_limit = 512000 ``` That made GPT-5.4 very useful for large repositories and long-running coding sessions. But with GPT-5.5, even though the model itself is supposed to be better at long-context reasoning and large coding tasks, Codex subscription users are now capped at 400K context. In practice, that makes GPT-5.5 feel like an upgrade in model quality but a downgrade in long-context usability inside Codex. I understand that 1M context is expensive. I also understand why 400K might be a reasonable default for most users. But I do not think it should be the hard limit for everyone. For advanced Codex users, especially those working on large codebases, the choice between compaction and full context matters a lot. Codex compaction is good, but it is still a tradeoff. During complex debugging, architecture analysis, or multi-file refactors, I would often rather spend mo
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