use-cases/api-integration-migrations.md Codex Docs, 2026-04-24 12:28 UTC → 2026-05-07 20:02 UTC

1# Upgrade your API integration | Codex use cases1---

2 2name: Upgrade your API integration

3Codex use cases3tagline: Upgrade your app to the latest OpenAI API models.

4 4summary: Use Codex to update your existing OpenAI API integration to the latest

5![](/assets/OpenAI-black-wordmark.svg)5 recommended models and API features, while checking for regressions before you

6 6 ship.

7![Codex](/assets/OAI_Codex-Lockup_Fallback_Black.svg)7skills:

8 8 - token: $openai-docs

9Codex use case9 url: https://github.com/openai/skills/tree/main/skills/.curated/openai-docs

10 10 description: Pull the current model, migration, and API guidance before Codex

11# Upgrade your API integration11 makes edits to your implementation.

12 12bestFor:

13Upgrade your app to the latest OpenAI API models.

14 

15Difficulty **Intermediate**

16 

17Time horizon **1h**

18 

19Use Codex to update your existing OpenAI API integration to the latest recommended models and API features, while checking for regressions before you ship.

20 

21## Best for

22 

23 - Teams upgrading from older models or API surfaces13 - Teams upgrading from older models or API surfaces

24 - Repos that need behavior-preserving migrations with explicit validation14 - Repos that need behavior-preserving migrations with explicit validation

15starterPrompt:

16 title: Upgrade the Integration Safely

17 body: >-

18 Use $openai-docs to upgrade this OpenAI integration to the latest

19 recommended model and API features.

25 20 

26# Contents

27 

28[← All use cases](https://developers.openai.com/codex/use-cases)

29 

30Copy page [Export as PDF](https://developers.openai.com/codex/use-cases/api-integration-migrations/?export=pdf)

31 

32Use Codex to update your existing OpenAI API integration to the latest recommended models and API features, while checking for regressions before you ship.

33 

34Intermediate

35 

361h

37 

38Related links

39 

40[Latest model guide](https://developers.openai.com/api/docs/guides/latest-model) [Prompt guidance](https://developers.openai.com/api/docs/guides/prompt-guidance) [OpenAI Docs MCP](/learn/docs-mcp) [Evals guide](https://developers.openai.com/api/docs/guides/evals)

41 

42## Best for

43 

44 - Teams upgrading from older models or API surfaces

45 - Repos that need behavior-preserving migrations with explicit validation

46 21 

47## Skills & Plugins22 Specifically, look for the latest model and prompt guidance for this

23 specific model.

48 24 

49- [OpenAI Docs](https://github.com/openai/skills/tree/main/skills/.curated/openai-docs)

50 25 

51 Pull the current model, migration, and API guidance before Codex makes edits to your implementation.26 Requirements:

52 27 

53| Skill | Why use it |28 - Start by inventorying the current models, endpoints, and tool assumptions

54| --- | --- |29 in the repo.

55| [OpenAI Docs](https://github.com/openai/skills/tree/main/skills/.curated/openai-docs) | Pull the current model, migration, and API guidance before Codex makes edits to your implementation. |

56 30 

57## Starter prompt31 - Identify the smallest migration plan that gets us onto the latest

32 supported path.

58 33 

59Use $openai-docs to upgrade this OpenAI integration to the latest recommended model and API features.

60Specifically, look for the latest model and prompt guidance for this specific model.

61 Requirements:

62- Start by inventorying the current models, endpoints, and tool assumptions in the repo.

63- Identify the smallest migration plan that gets us onto the latest supported path.

64 - Preserve behavior unless a change is required by the new API or model.34 - Preserve behavior unless a change is required by the new API or model.

65 - Update prompts using the latest model prompt guidance.

66- Call out any prompt, tool, or response-shape changes we need to review manually.

67 35 

68[Open in the Codex app](codex://new?prompt=Use+%24openai-docs+to+upgrade+this+OpenAI+integration+to+the+latest+recommended+model+and+API+features.%0A%0ASpecifically%2C+look+for+the+latest+model+and+prompt+guidance+for+this+specific+model.%0A%0ARequirements%3A%0A-+Start+by+inventorying+the+current+models%2C+endpoints%2C+and+tool+assumptions+in+the+repo.%0A-+Identify+the+smallest+migration+plan+that+gets+us+onto+the+latest+supported+path.%0A-+Preserve+behavior+unless+a+change+is+required+by+the+new+API+or+model.%0A-+Update+prompts+using+the+latest+model+prompt+guidance.+%0A-+Call+out+any+prompt%2C+tool%2C+or+response-shape+changes+we+need+to+review+manually. "Open in the Codex app")

69 

70Use $openai-docs to upgrade this OpenAI integration to the latest recommended model and API features.

71Specifically, look for the latest model and prompt guidance for this specific model.

72 Requirements:

73- Start by inventorying the current models, endpoints, and tool assumptions in the repo.

74- Identify the smallest migration plan that gets us onto the latest supported path.

75 - Preserve behavior unless a change is required by the new API or model.

76 - Update prompts using the latest model prompt guidance. 36 - Update prompts using the latest model prompt guidance.

77- Call out any prompt, tool, or response-shape changes we need to review manually.37 

38 - Call out any prompt, tool, or response-shape changes we need to review

39 manually.

40relatedLinks:

41 - label: Latest model guide

42 url: /api/docs/guides/latest-model

43 - label: Prompt guidance

44 url: /api/docs/guides/prompt-guidance

45 - label: OpenAI Docs MCP

46 url: /learn/docs-mcp

47 - label: Evals guide

48 url: /api/docs/guides/evals

49---

78 50 

79## Introduction51## Introduction

80 52 

100Make sure to build an evals pipeline that you can run every time you make changes to your integration, to verify there is no regression in behavior.72Make sure to build an evals pipeline that you can run every time you make changes to your integration, to verify there is no regression in behavior.

101 73 

102This [cookbook guide](https://developers.openai.com/cookbook/examples/evaluation/building_resilient_prompts_using_an_evaluation_flywheel) covers in detail how to do this using our [Evals API](https://developers.openai.com/api/docs/guides/evals).74This [cookbook guide](https://developers.openai.com/cookbook/examples/evaluation/building_resilient_prompts_using_an_evaluation_flywheel) covers in detail how to do this using our [Evals API](https://developers.openai.com/api/docs/guides/evals).

103 

104## Related use cases

105 

106[![](/images/codex/codex-wallpaper-2.webp)

107 

108### Add Mac telemetry

109 

110Use Codex and the Build macOS Apps plugin to add a few high-signal `Logger` events around...

111 

112macOS Code](https://developers.openai.com/codex/use-cases/macos-telemetry-logs)[![](/images/codex/codex-wallpaper-2.webp)

113 

114### Create a CLI Codex can use

115 

116Ask Codex to create a composable CLI it can run from any folder, combine with repo scripts...

117 

118Engineering Code](https://developers.openai.com/codex/use-cases/agent-friendly-clis)[![](/images/codex/codex-wallpaper-1.webp)

119 

120### Create browser-based games

121 

122Use Codex to turn a game brief into first a well-defined plan, and then a real browser-based...

123 

124Engineering Code](https://developers.openai.com/codex/use-cases/browser-games)