Document Extraction
The read_file tool automatically converts common document formats to readable text, so the agent can inspect a PDF or spreadsheet the same way it reads source code.
Supported formats
| Format | Extensions | Converter | Availability |
|---|---|---|---|
| Jupyter notebooks | .ipynb | Built-in (stdlib) | Always |
| Word documents | .docx | Built-in (stdlib) | Always |
| Excel workbooks | .xlsx | Built-in (stdlib) | Always |
.pdf | Optional anydoc converter | Auto-installed on first use* | |
| Legacy Office | .doc, .ppt, .xls, .pptx, and variants | Optional anydoc converter | Auto-installed on first use* |
| OpenDocument | .odt, .ods, .odp | Optional anydoc converter | Auto-installed on first use* |
| Rich text / eBooks | .rtf, .epub | Optional anydoc converter | Auto-installed on first use* |
* The optional converter is the firecrawl-anydoc package, installed lazily where installs are permitted (security.allow_lazy_installs in config.yaml). Without it, the three stdlib formats still work; other formats fall back to the binary-file guard.
Conversion output is Markdown, paginated through read_file's normal offset/limit window. Documents over 50 MB are refused to keep tool turns bounded.
Extraction works with remote terminal backends (Docker, Modal, SSH): the file's bytes are transferred across the backend boundary and converted host-side, so a document inside a sandbox reads the same as a local one.
Scanned PDFs: the coverage warning
PDF conversion reads the text layer only. Pages that are scanned images — common in legal documents, resale packages, signed contracts, faxes — contain no text layer and silently convert to nothing. The telltale signature is section headers with empty bodies.
When a meaningful share of pages yields no text (over 20% of the document, or 10+ pages absolute), read_file prepends a warning to the extraction. Each unreadable gap is labeled with the last text extracted before it — usually a section divider — so the agent can target only the gaps it actually needs instead of OCRing the whole document:
[EXTRACTION COVERAGE WARNING: 198 of 311 pages in this PDF yielded no
text. ... Unreadable gaps, each labeled with the last text extracted
before it:
pages 42-77 (36 pages) — after "Antigua Maintenance Corp Bylaws" (p41)
pages 92-213 (122 pages) — after "... Covenants, Codes and Regulations" (p91)
page 224 (1 page) — after "... Insurance Declaration Pages" (p223)
Decide which gaps you actually need — do NOT OCR or render everything. ...]
The warning lists the exact page ranges and the recovery paths:
- A few pages — render + vision. Convert the pages to images and read them with the vision tool:
Then inspect each image withpdftoppm -jpeg -r 150 -f 92 -l 94 document.pdf /tmp/page
vision_analyze. Zero extra dependencies (poppler is required for the detection itself). - Many pages — OCR. The
ocr-and-documentsskill covers bulk OCR with marker-pdf (90+ languages, handles equations and tables; ~3-5 GB install).
Detection uses poppler's pdftotext for per-page text counts. If poppler is not installed, extraction still works — the coverage check is silently skipped.
The agent handles the warning on its own — it will offer to render or OCR the missing pages. If you're reading extractions yourself, treat "header with an empty body" as a scanned section, not a missing one.