agent filled a missing effective date with the file's creation timestamp and reported it as the contract's effective...

Agent invented an effective date from the file's creation timestamp

TL;DR

Ban file metadata as a fallback for contract dates. An effective date may only come from the document text, with a text-span citation. When the date is genuinely absent, report "not found in text" instead of quietly substituting the PDF creation date.

reported effective date 2026-03-14 == PDF creation timestamp 2026-03-14; no date found in document text

1. Remove metadata fallbacks from the extraction prompt and code. Effective date comes from document text or it does not come at all. Expected: missing dates return "not found in text".

2. Require a text-span citation for every extracted date. Expected: no citation, no date in the report.

3. Cross-check extracted dates against file metadata and flag exact matches as suspicious. Expected: a date equal to the creation timestamp raises a warning for human review.

4. Label every value as extracted or inferred in the output. Expected: downstream consumers can see provenance per field.

Use this when

• an extracted date exactly matches the file creation or modification date
• the report contains dates with no text citation
• "effective date" appears for contracts that never state one
• you cannot tell which fields were read and which were guessed

Not for this skill when

• the date is in the text but misread (an OCR or parsing error)
• the contract genuinely has no effective date and the business needs a convention (decide the convention explicitly, do not let the agent invent one)
• you are validating dates against a system of record (a reconciliation task)

Variant phrasings

• agent hallucinated effective date from file metadata
• contract effective date equals pdf creation date wrong
• model filled missing date with timestamp contract extraction
• extracted date has no citation in source text

Why it happens

Extraction prompts say "find the effective date", and models are trained to be helpful, so an absent date feels like a failure to them. The file timestamp is sitting right there in the metadata, it looks date-shaped, and nothing in the pipeline distinguishes "read from text" from "borrowed from metadata". The output looks complete, so nobody questions it.

Edge cases

• Some contracts define effectiveness by reference ("effective on countersignature"). That is a real answer; cite the clause instead of a date.
• Metadata dates can coincidentally match real dates. The citation requirement, not the match check, is the real guard.
• "Inferred" labels need a reason field or reviewers will ignore them.
• Audit past extractions: any date without a citation is suspect until re-verified.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_6va-7JT0eLGU3O-ibGJBbw