GPT-5.6 Sol · configuration
Run the same task at faster and deeper reasoning settings: prefer speed for short questions, then increase reasoning for planning, research, writing, coding, and decisions; OpenAI’s 68% figure is an internal relative change, not public accuracy.
Choose a ChatGPT reasoning setting for each task using evidence: favor a faster response for short questions, and increase reasoning for multi-step planning, research, writing, coding, and decisions. The output must compare quality, errors, omissions, and time rather than judging style alone.
Use the ChatGPT web, mobile, or desktop client and record account type, client version, and date.
Prepare fixed input, tool conditions, and acceptance criteria for the same task.
Confirm the setting names shown by the client; do not translate a UI slider directly into the API’s reasoning.effort.
For dates, numbers, sources, rules, or high-risk conclusions, prepare sources and a human review step.
Classify the task as a short fact or edit, multi-step work, or work that requires source verification.
Start simple tasks at the faster setting; before increasing reasoning for complex work, provide the missing context, success criteria, and tools.
Run the same input at faster and deeper settings, recording factual errors, omissions, completion time, revisions, and tool use.
Keep the deeper setting only when it produces repeatable quality gains; otherwise return to the faster setting.
For Free or Go accounts, confirm Luna and the Thinking button in the current interface rather than applying Plus/Pro options to every account.
Each record includes model name, setting, client, date, input version, and tool use.
The routing decision follows fixed acceptance criteria and a reproducible comparison; internal relative figures are not written as public accuracy.
Source-dependent answers list their basis and flag uncertain facts for human review.
The recommendation explains quality, speed, and cost or consumption trade-offs together.
If both settings produce factual errors, add sources or narrow the question instead of only increasing reasoning.
If the deeper setting is too slow or expensive, split the task, remove irrelevant context, or return to the faster setting.
Reject a longer answer that does not improve the acceptance score.
If the slider or button is unavailable, do not guess an API field; record the client difference and consult current product guidance.
The 68% figure is an internal relative change; the source does not disclose samples, per-question inputs, or external reproduction, so it is not a general accuracy rate.
The page describes ChatGPT chat and cannot establish identical behavior in Codex or the API.
A reasoning setting changes model investment; it does not replace source checking, permissions, human approval, or safety controls.
Treat GPT‑5.6 Sol as the same model in ChatGPT and adjust its reasoning investment by task: use a faster setting for simple questions, then increase the reasoning setting for planning, research, writing, coding, and decision-making.
Suitable tasks: client-side routing for factual questions, web searches, planning, research, writing, coding, and multi-step decision-making.
Unsuitable tasks: scenarios that require precise API control of reasoning.effort or a custom service tier; this page describes only the ChatGPT product slider.
Applicable model version: the updated GPT‑5.6 Sol in ChatGPT; the default model for Free and Go users is GPT‑5.6 Luna.
Applicable client, Agent, or API: ChatGPT on the web, mobile, and desktop; the page does not disclose a corresponding API field.
Recommended reasoning setting and parameters: choose the faster setting for everyday questions; choose a higher reasoning setting for multi-step planning, research, writing, coding, or decision-making; exact setting names depend on the client.
The following is a client configuration card organized from the official routing guidance, not API request syntax:
Task routing:
1. If the question is a simple fact, short rewrite, or minor edit, start with GPT‑5.6 Sol's faster reasoning setting.
2. If the task requires multi-step planning, research, writing, coding, or a high-value decision, increase the reasoning setting before submitting.
3. If the answer depends on dates, numbers, sources, rules, or assumptions, ask the model to verify the basis first and then provide a conclusion.
4. If key facts remain uncertain, do not rely on simply increasing the reasoning setting; add sources or perform a human review.
5. For Free/Go accounts, use Luna for routine text tasks; use Luna's “Thinking” button for harder problems.Run the same question separately at a faster and a higher reasoning setting.
Compare factual errors, omissions, answer length, and completion time rather than looking only at writing style.
For planning, research, writing, and coding tasks, keep a fixed acceptance criterion, then decide whether to increase the setting.
Record the client, date, model setting, and whether tools were used; the page explicitly states that the updated chat Sol is not the same as the Sol version that supports Codex.
OpenAI describes the updated Sol as more focused, adjusting detail to the question, reducing unhelpful formatting, and correcting unhelpful agreement.
In internal evaluations using financial, medical, and legal prompts, the proportion of answers with at least one factual error fell by about 68% relative to GPT‑5.5 Instant.
Plus/Pro users can switch between instant answers and more in-depth thinking with the slider; the page does not disclose evaluation samples, per-question inputs, or external reproduction experiments.
Free users switch to Luna and can use the “Thinking” button for harder questions; file uploads, images, and other tools remain limited.
The 68% figure is a relative change from OpenAI's internal evaluation, not a publicly reproducible accuracy rate.
The page says this update applies only to the ChatGPT chat experience; it should not be used to infer that Codex or API model behavior is exactly the same.
Increasing the reasoning setting takes more time or consumption and does not necessarily deliver an equivalent quality gain; record A/B results on representative tasks.
The official announcement summarizes the update as “more focused answers” and explicitly places instant answers and more in-depth thinking within the same Sol experience.
OpenAI · Source date: 2026-08-06 · Edited: 2026-09-20
Read the original sourceGPT-5.6 Sol
Run this guide in the environment listed above. Downloading does not transfer the template or establish model availability for your account.