fix: Save scan instructions before Deep workers start

[ianw-oai]

Summary

The SDK sent scan instructions to the parent agent but did not save them with the scan. Deep workers read the saved scan context, so they could start without these instructions.

Save options.scanPrompt in scans.user_context during registration, before workers start. This does not depend on the parent agent to copy the text.

Changes

• Send scan instructions through the existing stdin transport.
• Preserve UTF-8 text, whitespace, and line endings without trimming.
• Save the context in the existing registration transaction.
• Test the saved context and Deep worker prompt with synthetic inputs. Check scans without instructions and scans with knowledge-base input.

Testing

All checks passed on the final patch:

• Focused API and Deep workbench tests: 150 passed, 2 skipped, 0 failed.
• pnpm run test --seed 12345 --only-failures: 1,484 passed, 29 skipped, 0 failed.
• pnpm run test --only-failures (seed 666922896): 1,484 passed, 29 skipped, 0 failed.
• pnpm run types
• pnpm run format
• git diff --check

Risk and rollout

No public commands, flags, settings, or prompt text change. Scans without a scan prompt keep the existing behavior. Knowledge-base handling is unchanged.

The change uses the existing context field and transaction. No database migration or special rollout step is required. It applies to new scan registrations and does not change saved scans.

Public disclosure review

• No customer, partner, prospect, or user identities, data, or identifying details are included.
• No credentials, personal data, private source, scan findings, or nonpublic links or tickets are included.
• I reviewed the branch name, title, description, commits, changes, comments, logs, screenshots, attachments, and links for public disclosure.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
🔒 Security Review	✅ Completed 2026-08-21T16:41:20.967774Z	0a6c8ad	Draft marked ready

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