GPT-5.3 Codex Spark

Tool callingStructured outputReasoningImage inputFile input

Website

Coding-optimized GPT model for repository edits, reviews, and agentic software work

Context: 128K
Released: 8mo ago

Sources:models.dev

Benchmarks

DeepSWE is the primary coding benchmark where an exact model evaluation exists. Other sourced evaluations appear below; missing scores are not zero.

Not evaluated in DeepSWE 1.1 as of 2026-09-22. Results are only shown for exact model versions in the official dataset. Official leaderboard.

No benchmark results have been matched to this model yet.

Specifications

Developer: OpenAI
Model family: GPT
Type: Language model
Predecessor: —
Successor: —
Released: February 5, 2026
Model ID: openai/gpt-5.3-codex-spark
Openness: Closed
License: —
Input modalities: text, image, file
Output modalities: text
Modality: text+image+file->text
Max output tokens: 32K
Knowledge cutoff: 2025-08-31
Hugging Face: —
Source freshness: Metadata synced Oct 8, 2026, 10:17 PM UTC

Additional source evidence

Source model: openai/gpt-5.3-codex-spark
Source family: gpt-codex-spark
Last updated: 2026-02-05
Knowledge cutoff: 2025-08-31
Model context: 128K
Maximum input: 100K
Model output limit: 32K
Open weights: No
File attachments: Yes
Reasoning: Yes
Tool calling: Yes
Structured output: Yes
Temperature control: No

Complete source record (JSON)

{
  "id": "openai/gpt-5.3-codex-spark",
  "name": "GPT-5.3 Codex Spark",
  "description": "Coding-optimized GPT model for repository edits, reviews, and agentic software work",
  "family": "gpt-codex-spark",
  "last_updated": "2026-02-05",
  "knowledge": "2025-08-31",
  "attachment": true,
  "reasoning": true,
  "tool_call": true,
  "structured_output": true,
  "temperature": false,
  "modalities": {
    "input": [
      "text",
      "image",
      "pdf"
    ],
    "output": [
      "text"
    ]
  },
  "limit": {
    "context": 128000,
    "input": 100000,
    "output": 32000
  },
  "release_date": "2026-02-05",
  "open_weights": false
}

Infrastructure

Provider availability

All providers

Provider endpoint data will appear after this model's first OpenRouter endpoint sync.

Text provenance

EU · product-scoped

OpenAI textGrain watermarking

In the EU, ChatGPT-generated text uses textGrain. OpenAI says API customers can opt in globally for select models, so watermarking depends on the product surface and configuration.

Official explanation