PR #26331: feat(openai): add gpt-image-2 to model prices

• Repository: BerriAI/litellm
• Author: Kcstring
• State: open | merged: False
• Link: https://github.com/BerriAI/litellm/pull/26331

Description (problem / solution / changelog)

What does this PR do?

Adds gpt-image-2 to the model prices and context window registry.

gpt-image-2 was released on 2026-04-21 and is available in the OpenAI API and Codex. It was missing from litellm's model cost map, causing litellm.get_model_info("gpt-image-2") to return None and cost calculation to fail.

Pricing (from https://openai.com/api/pricing/)

Token-based billing:

• Image input: $8.00 / 1M tokens
• Image output: $32.00 / 1M tokens

Per-image pricing at 1024×1024:

• Low quality: $0.006
• Medium quality: $0.053
• High quality: $0.211

Changes

• Added gpt-image-2 base entry with token-based pricing to model_prices_and_context_window_backup.json
• Added low/medium/high per-quality entries for 1024×1024 resolution
• Added 3 unit tests in TestGPTImage2CostCalculator

Tests

LITELLM_LOCAL_MODEL_COST_MAP=True pytest tests/test_litellm/test_gpt_image_cost_calculator.py -q
# 11 passed

Closes #26232

Relates to litellm_oss_branch

Changed files

• litellm/litellm_core_utils/llm_cost_calc/utils.py (modified, +2/-2)
• litellm/llms/anthropic/experimental_pass_through/responses_adapters/transformation.py (modified, +4/-1)
• litellm/model_prices_and_context_window_backup.json (modified, +93/-1)
• model_prices_and_context_window.json (modified, +93/-1)
• tests/test_litellm/llms/anthropic/experimental_pass_through/responses_adapters/test_responses_adapters_transformation.py (modified, +48/-1)
• tests/test_litellm/test_gpt_image_cost_calculator.py (modified, +66/-0)