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DeprecatedChat Models

OpenAI

o3

OpenAI reasoning model for technical and visual analysis. Its deprecated API snapshot retires December 11, 2026.

Reasoning

At a glance

Know the model before you prompt.

OpenAI API specifications
Context window
200,000 tokens
Maximum output
100,000 tokens
Inputs → output
Text + Images → Text
Knowledge cutoff
June 1, 2024

API model ID: o3

Capabilities & boundaries

What it supports. Where the limits are.

Tool support requires the appropriate API integration; a supported tool is not automatically active in every chat.

Supported API features and tools

  • Streaming responses
  • Function calling and structured outputs
  • Image input and prompt caching
  • Web search, file search, image generation tools, code interpreter, and MCP

Before you choose

  • No native audio or video support; native output is text.
  • Fine-tuning is not supported.
  • The o3-2025-04-16 API snapshot is scheduled to retire December 11, 2026. Plan and test a replacement rather than assuming indefinite access.
  • Visual reasoning and a large output allowance do not guarantee correct measurements, calculations, or conclusions.

Choose the reasoning effort

lowmediumhigh

OpenAI’s reasoning guidance lists low, medium, and high for o3. No default is asserted here. Compare the settings on your own technical examples; higher effort can spend more tokens and time without guaranteeing a better answer.

Unsupported settings: none, minimal, xhigh, max.

  • Chat Completions, Responses, and Batch are supported. The listed built-in tools require a suitable Responses API integration.
  • The documented snapshot is o3-2025-04-16; the retirement notice applies to that exact snapshot.
  • API rate limits depend on usage tier; the free API tier is not supported.

Put it to work

Start with a more useful prompt.

Original examples from EZ Ai Assist. Adapt these to your task and the features available in your workspace.

Workflow 01

Trace a concurrency failure

Build a testable explanation from code and timestamped observations.

Use these code excerpts and timestamped logs to analyze the intermittent concurrency failure. Identify the shared state, possible interleavings, and evidence that supports or contradicts each hypothesis. Cite the relevant code and log entries. Propose one minimal reproduction and the assertions needed to distinguish the leading explanations. Do not claim you ran the code.

Workflow 02

Check a scientific argument

Evaluate the supplied reasoning without importing unsupported results.

Review this technical argument using only the definitions, observations, and equations provided. Identify where each conclusion follows, which assumptions are unstated, and whether a counterexample is possible within the stated constraints. Explain any unit or boundary-condition problems. Finish with the smallest additional experiment or calculation that would reduce the main uncertainty.

Workflow 03

Compare a diagram with its specification

Use image input as evidence, with explicit limits on what is visible.

Compare this system diagram with the accompanying written specification. List components, connections, and boundaries visible in the diagram, then identify inconsistencies with the text. Cite the image region and specification section for each issue. Mark ambiguous symbols as uncertain and ask clarifying questions instead of inferring hidden connections.

Developer reference

OpenAI API pricing

These are OpenAI API reference prices, not EZ Ai Assist subscription prices.

View EZ Ai Assist plans
Standard processing · USD per 1,000,000 tokens
Token typePrice
Input$2.00
Cached input$0.50
Output$8.00
  • These are Standard o3 rates; do not confuse lower Flex or Batch prices with this processing tier.
  • Cached-input pricing applies only to eligible cached tokens. No separate long-context surcharge is listed in the reviewed table.
  • Reasoning contributes to billed output usage. Tool calls and other service tiers can add or change charges; check the current pricing documentation.

Common questions

A few things worth knowing.

Is o3 being retired?

OpenAI announced the deprecation of o3-2025-04-16 on June 11, 2026, with API shutdown scheduled for December 11, 2026. The notice recommends GPT-5.6 Sol. This is a specific API snapshot lifecycle, not a claim that the EZ Ai Assist page or app access has already disappeared.

How should I evaluate a replacement?

Keep a small set of representative prompts, expected results, failure cases, and latency targets. Run them against the replacement and inspect differences in answers, tool behavior, and total usage. Update integrations before the retirement date rather than treating a new model name as a drop-in guarantee.

What reasoning efforts does o3 support?

The documented choices are low, medium, and high. This guide does not assert an unverified default or add newer models’ none, xhigh, or max settings. Set the effort explicitly when comparing API results.

Can o3 analyze images?

Yes, image input is supported. Ask it to distinguish visible evidence from assumptions and supply underlying data for numerical work. Native output is text; image generation is a separate tool and audio/video are not native modalities.

Can it return structured data or use tools?

The API supports structured outputs and function calling, plus the listed Responses tools. A schema constrains format, not factual accuracy. Validate identifiers, calculations, and permissions before acting on a result.

Why do I see different o3 prices elsewhere?

OpenAI has different processing tiers. This guide shows Standard prices of $2 input, $0.50 eligible cached input, and $8 output per million tokens. Do not mix Flex or Batch rates into a Standard estimate; tool fees can also matter.

Are these examples guaranteed to work in my plan?

No. These are original workflow suggestions, not benchmarks or promises about app controls. Check current EZ Ai Assist model access and supported inputs, share only authorized material, and verify the result before using it.

Check the source

Official documentation

Specifications and API prices checked on . Example prompts and workflow advice are editorial guidance from EZ Ai Assist.

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