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AI Atlas
ModelRetiredProprietary

GPT-5.1-Codex-Max

OpenAIdevelopers.openai.com/api/docs/models/gpt-5.1-co

A version of GPT-5.1-codex optimized for long running tasks.

quality72

Updated 40 min ago · first seen 11 Sept 2026

model_01M293VC5D6R1T4YX4QXP13HX6

Context
400K tokens
T2 · 40 min ago
Released
4 Dec 2025
T2 · 40 min ago

As of

Rewind the record: see this entity's attributes exactly as AI Atlas knew them on a given day.

Claim history · Supported parameters

1 claims · 1 propertiesShow all properties

Supported parameterssupported_parameters1

Claim history for Supported parameters
ValueValid from → toStatusSourceConfidenceExtractor
include_reasoning, max_completion_tokens, reasoning, reasoning_effort, response_format, seed, structured_outputs, tool_choice, toolscurrentcurrentOpenRouter public model & pricing listingT2mediumdeterministic

Claims are temporal and append-only: a new observation closes the previous claim (valid_to) instead of overwriting it. Conflicting claims from different sources are kept side by side and flagged — never averaged. Methodology →