Models & pricing

GPT-5.6 Luna

Model ID

gpt-5.6-luna

Context window

272k

Provider

OpenAI

Speed

Fast

Cost

Low

Intelligence

Moderate

GPT-5.6 Luna is OpenAI's lowest-cost model in the GPT-5.6 family available in Ask ASUME. It is well suited to straightforward questions where speed and cost matter more than the stronger reasoning capability of Terra or Sol.

Selecting GPT-5.6 Luna changes how an Ask is answered. It does not change how ASUME builds or maintains the underlying company understanding.

Strengths

Lowest GPT-5.6 cost

Luna is the least expensive GPT-5.6 option in the current ASUME catalogue, allowing the same included allowance to support more model usage.

Fast responses

A strong choice when a straightforward company question should be answered quickly.

Efficient for bounded tasks

Works well when the relevant company context is clear and the Ask does not require extended reasoning across many considerations.

Efficient everyday use

Useful when you want an OpenAI model without paying Terra or Sol rates for simpler work.

Limitations

Less capable than Terra and Sol

GPT-5.6 Terra and GPT-5.6 Sol are better suited to questions that require deeper or more extended reasoning.

Not suited to demanding reasoning

Luna has less capacity for difficult problems, competing explanations, or analysis involving many interacting factors.

Limited for more involved analysis

When an Ask requires more interpretation or synthesis, Corollary or GPT-5.6 Terra may be a better fit.

Available context

Maintained understanding

Uses the structured company understanding ASUME has already constructed and maintains over time. Answers come from that context rather than rebuilding the company from the beginning for every question.

Evidence & assumptions

Can use relevant evidence, sources, and explicit assumptions associated with the maintained understanding when they are made available to the Ask.

Multi-company context

Can reason across the maintained understanding of multiple companies when a question involves comparison, relationships, or portfolio-level analysis.

Available capabilities

Can use the capabilities ASUME makes available for the Ask. Availability depends on the product, workspace permissions, and the capabilities supported at the time of the request.

When to use GPT-5.6 Luna

Choose GPT-5.6 Luna when the question is straightforward and minimizing cost is more important than additional reasoning capability.

Straightforward questions

Use Luna for Asks that can be answered from a limited amount of clear company context.

High-volume everyday Asks

Use Luna when you expect many relatively simple questions and want more usage from the same allowance.

Cost-sensitive work

Use Luna when you want an OpenAI model at the lowest published GPT-5.6 rate.

Quick company checks

Use Luna for fast questions about a company's maintained state that do not require extended reasoning.

Pricing

GPT-5.6 Luna is a directly selectable third-party model in Ask ASUME. Usage is billed at the ASUME rates below. All prices are per million tokens.

Name	Input	Cache Write	Cache Read	Output
GPT-5.6 Luna	€0.22	€0.27	€0.022	€1.30

The rates above are billed by ASUME and may differ from OpenAI's own API pricing. Choosing GPT-5.6 Luna affects only the model usage associated with the Ask.