# Codex GPT 5.6 Sol Reduced to 258K Context Window > Source: > Published: 2026-07-13 14:50:28+00:00 - [Notifications](/login?return_to=%2Fopenai%2Fcodex)You must be signed in to change notification settings - [Fork 14.5k](/login?return_to=%2Fopenai%2Fcodex) # 🚨 [SEVERE REGRESSION] GPT-5.6 Sol context cut again: 353K → 258K despite advertised 1.05M #32806 [CLIIssues related to the Codex CLI](https://github.com/openai/codex/issues?q=state%3Aopen%20label%3A%22CLI%22)Issues related to the Codex CLI [bugSomething isn't working](https://github.com/openai/codex/issues?q=state%3Aopen%20label%3A%22bug%22)Something isn't working [contextIssues related to context management (including compaction)](https://github.com/openai/codex/issues?q=state%3Aopen%20label%3A%22context%22)Issues related to context management (including compaction) ## Description ### What version of Codex CLI is running? `codex-cli 0.144.3` ### What subscription do you have? Paid ChatGPT-authenticated Codex subscription. Exact tier is redacted for privacy because the catalog/runtime regression is not account-specific. ### Which model were you using? `gpt-5.6-sol` ### What platform is your computer? Linux x86_64. Exact host and kernel details are redacted because they are unrelated to server-delivered model metadata. ### What terminal emulator and version are you using (if applicable)? Codex desktop/CLI environment. Local application and project identifiers are redacted. ### Codex doctor report Not included to avoid publishing machine, account, path, repository, and runtime metadata. The relevant sanitized version, model-catalog fields, and runtime values are included below. ### What issue are you seeing? ## Summary Codex has silently reduced the usable context window for `gpt-5.6-sol` **again**. The previous server-delivered Codex model catalog exposed: ``` { "context_window": 372000, "max_context_window": 372000, "effective_context_window_percent": 95 } ``` That produced a `353,400` -token effective runtime window: ``` 372,000 × 95% = 353,400 ``` The current freshly fetched catalog now exposes: ``` { "context_window": 272000, "max_context_window": 272000, "effective_context_window_percent": 95 } ``` Codex therefore now reports only `258,400` effective tokens: ``` 272,000 × 95% = 258,400 ``` This is a further **95,000-token / 26.9% reduction** from the already restricted 353.4K Codex window. It is not UI rounding. Sanitized historical runtime records repeatedly report `model_context_window: 353400` before the rollout and `model_context_window: 258400` afterward. No local `model_context_window` or auto-compaction override is configured. Issue [#31860](https://github.com/openai/codex/issues/31860) already documented that the earlier 353.4K Codex cap was far below the published GPT-5.6 Sol model specification. This report covers the new and materially worse regression from 353.4K to 258.4K. The official GPT-5.6 Sol model page still advertises: - 1,050,000-token context window - 922,000 maximum input - 128,000 maximum output Source: [https://developers.openai.com/api/docs/models/gpt-5.6-sol](https://developers.openai.com/api/docs/models/gpt-5.6-sol) At the same 95% effective-window policy, the advertised model would provide approximately `997,500` usable tokens. Codex now exposes only `258,400` , or **25.9%** of that comparable effective capacity. ## Why this is unacceptable This combination is infuriating: OpenAI advertises a 1.05M flagship model, initially restricts it to 353K in Codex, and then silently cuts it again to 258K. Paying users are left with more compactions, lost working context, disrupted long-running tasks, and no advance notice or explanation. This feels dismissive of paying users and materially undermines trust in Codex as a professional development tool. Repository-scale analysis, long-running implementation work, multi-agent coordination, large specifications, and tool-heavy sessions all depend on stable context capacity. Context size is not a cosmetic setting that can be silently reduced by another 26.9%. The pricing situation makes this even more frustrating. The same official model page states that requests above 272K input are priced at `2×` input and `1.5×` output for the full request. Codex now caps the raw window at exactly 272K, so users cannot even choose to access the published long-context tier through Codex. To be precise: this report concerns the Codex product limit under ChatGPT authentication. The pricing comparison refers to OpenAI's published API long-context policy; it demonstrates that long-context capacity exists and is explicitly priced, while Codex prevents access to it. Major competing platforms already offer 1M-class context: - Google documents Gemini models with 1M or larger context windows: [https://ai.google.dev/gemini-api/docs/long-context](https://ai.google.dev/gemini-api/docs/long-context) - xAI documents a 1,000,000-token window for its flagship Grok 4.3: [https://docs.x.ai/developers/models/grok-4.3](https://docs.x.ai/developers/models/grok-4.3) - Anthropic documents a 1M context option for Claude Sonnet 4: [https://docs.anthropic.com/en/docs/about-claude/pricing](https://docs.anthropic.com/en/docs/about-claude/pricing) A flagship coding product limited to 258K effective context is no longer competitive, especially when its underlying OpenAI model is publicly specified at 1.05M. ### What steps can reproduce the bug? - Run Codex CLI `0.144.3` with the official OpenAI provider and ChatGPT authentication. - Select `gpt-5.6-sol` . - Ensure there is no local `model_context_window` ,`model_auto_compact_token_limit` , provider, or project override. - Fetch or refresh the server-delivered model catalog. - Inspect the sanitized `gpt-5.6-sol` catalog entry. - Observe `context_window: 272000` ,`max_context_window: 272000` , and`effective_context_window_percent: 95` . - Start or continue a thread and inspect token-usage metadata. - Observe `model_context_window: 258400` . - Compare with earlier sanitized GPT-5.6 Sol thread records, which report `model_context_window: 353400` . The transition was observed on 2026-07-13. Old and new values briefly overlapped across existing and newly started threads, consistent with a phased or cached server-side catalog rollout. ### What is the expected behavior? - Codex should expose the full published 1.05M GPT-5.6 Sol context window, with a clear effective input/output reserve. - If a product-specific cap is unavoidable, it must be prominently documented before users select the model. - Context limits must not be silently reduced for existing or new paid-user workflows. - Active threads should retain the context contract under which they were started. - Users should be allowed to opt into the published long-context tier when they accept the associated usage or pricing impact. - As an immediate stopgap, restore the previous 372K raw / 353.4K effective Codex limit while full 1.05M support is implemented. - OpenAI should explain why the context was reduced, whether the change is temporary, which plans/surfaces are affected, and how usage accounting interacts with this cap. ### Additional information Related reports: [[Critical][Codex App] GPT-5.6 Sol is catalog-capped at 372K (353.4K effective) vs the 1.05M model spec #31860](https://github.com/openai/codex/issues/31860)— GPT-5.6 Sol was already capped at 372K raw / 353.4K effective instead of the published 1.05M.[Context window changes from 1M to 258K mid-thread #29039](https://github.com/openai/codex/issues/29039)— a GPT-5.5 thread changed from 1M to 258K mid-thread.[Reopen #19464 and support 1M context #30910](https://github.com/openai/codex/issues/30910)— request to restore 1M context support. Privacy note: this report intentionally excludes account identifiers, thread IDs, repository names, local paths, prompts, transcripts, and exact machine metadata. Only model metadata and aggregate context-window observations required to reproduce the regression are included. ## Metadata ## Metadata ### Assignees ### Labels [CLIIssues related to the Codex CLI](https://github.com/openai/codex/issues?q=state%3Aopen%20label%3A%22CLI%22)Issues related to the Codex CLI [bugSomething isn't working](https://github.com/openai/codex/issues?q=state%3Aopen%20label%3A%22bug%22)Something isn't working [contextIssues related to context management (including compaction)](https://github.com/openai/codex/issues?q=state%3Aopen%20label%3A%22context%22)Issues related to context management (including compaction)