| name | upload-github-attachment |
| description | Upload a local image or file to GitHub's user-attachments storage and return a URL suitable for issue, pull request, discussion, or comment Markdown. Use when Codex must embed local screenshots, videos, logs, or other evidence in GitHub content without committing the files to a repository. |
Upload GitHub Attachment
Use the bundled script so authentication, repository resolution, MIME detection, and URL extraction remain consistent.
Requirements
- Require the
gh CLI and curl.
- Prefer an existing
gh auth login session.
- When interactive
gh authentication is unavailable, require GH_TOKEN or GITHUB_TOKEN in the environment.
- Stop and ask the user to configure one of those authentication methods if
gh auth token cannot resolve a token. Never print, persist, or interpolate the token into diagnostic output.
Upload
Run from a checkout of the destination repository:
.agents/skills/upload-github-attachment/scripts/upload-github-attachment.sh /absolute/path/to/image.png
Specify the repository when the current directory cannot resolve it:
.agents/skills/upload-github-attachment/scripts/upload-github-attachment.sh \
--repo moeru-ai/airi \
/absolute/path/to/image.png
The script prints only the final https://github.com/user-attachments/assets/... URL. Embed it with  for an image or [label](URL) for another file.
Verification
- Request the returned URL and follow redirects.
- Require HTTP 200 and the expected content type.
- After creating or editing the GitHub content, reopen it and verify that the attachment renders.
The upload endpoint is currently undocumented by GitHub. Treat a rejected request as a blocking capability change instead of falling back to committing PR-only artifacts. Background and the observed Bearer-token flow: https://island94.org/2026/08/programmatically-upload-attachments-to-github-issues-pull-requests-comments.
