Summary

• write-document's generic-upload branch gated on if (input.sourceUpload), which is truthy for { filename: '', mimeType: '', contentBase64: '' } , an empty-but-present object, not an actual upload request.
• The same tool-calling paths that were sending an empty sourceEmailAttachment on ordinary writes (fixed in #2761's sibling commit 2e5e41920) also send this shape on sourceUpload, so the write got misrouted into the upload branch, decoded zero bytes from the empty contentBase64, and failed with "Decoded upload is empty" , the real content (e.g. a daily-agenda doc) was never saved.
• Gate on input.sourceUpload?.contentBase64 instead, so an empty upload reference is treated as absent and the write proceeds normally.

Traced from agent_tool_calls.id = 36f96438-927c-4a9d-8353-d627585447e9: this morning's daily-agenda orchestrator run sent a full agenda in content alongside an empty sourceUpload, hit this branch, failed, and the run gave up (mark-execution-as-failed) instead of saving the agenda. A DB check shows 9 write-document calls hit this exact error in the last 24 hours, across 3 different subagents/users.

Test plan

• pnpm --filter @zero/server exec vitest run src/mastra/tools/document/__tests__/writeDocumentTool.test.ts , 10 passed, including new regression test for the empty-sourceUpload case.
• Typecheck on the changed file is clean.

🤖 Generated with Claude Code

Greptile Summary

This PR corrects generic-upload routing for ordinary document writes that include an empty sourceUpload placeholder.

• Gates upload handling on non-empty contentBase64 rather than object presence.
• Adds a focused regression test proving that agenda content reaches the normal guarded writer.
• The implementation addresses the reported empty-string failure path, but the new test contains casts prohibited by the repository’s TypeScript rules.

Confidence Score: 4/5

The behavioral fix appears sound, but the explicit repository prohibition on TypeScript casts must be satisfied before merging.

The changed branch correctly restores normal writes for the observed empty placeholder, and the regression test would fail on the previous implementation; the only accepted concern is the test’s use of prohibited casts.

Files Needing Attention: apps/server/src/mastra/tools/document/tests/writeDocumentTool.test.ts

Important Files Changed

### Issue 1
apps/server/src/mastra/tools/document/__tests__/writeDocumentTool.test.ts:370-372
**Prohibited TypeScript Casts**

This test adds three explicit type assertions: two `as never` argument casts and a cast for the result shape. The repository requires typed inputs and inferred result types instead of casts that silence TypeScript errors. This requirement must be satisfied before merging.

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For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (1): Last reviewed commit: "fix(documents): ignore an empty sourceUp..." | Re-trigger Greptile}

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