pdf-tools

name

pdf-tools

description

Firm-owned PDF reading + actions over the in-app PDF viewer. Use whenever the user wants to work with a PDF: read it (extract its text to quote, summarize, or compare), annotate it (sticky notes, highlight boxes), list or fill its form fields (AcroForm), or stamp a signature (typed name + date, or a PNG signature image). Editing always writes a NEW copy (.annotated.pdf / .filled.pdf / .signed.pdf) — the original PDF is never modified. Self-contained; runs on the firm's own infrastructure; pairs with the in-app PDF viewer.

PDF reading + actions (text / annotate / fill-form / sign)

This skill is how this firm reads, annotates, fills, and signs PDFs with AI. It is self-contained: assets/pdf-agent.mjs imports vendored engines (pdf-lib for actions, pdf.js for text — pure JS, no native deps), so it runs in any workspace with no install. Do not hand-edit PDF bytes or reach for python or pdftotext (they may not exist on the machine) — use this tool. Every editing command writes a new file next to the source; the original PDF is never touched.

The tool

# ALWAYS FIRST: page count, page sizes (points), and every form field
# (name / type / current value / options) as JSON.
node .opencode/skills/pdf-tools/assets/pdf-agent.mjs inspect "<file.pdf>"

# READ the PDF: its text content per page as JSON ({ pageCount, pages: [{page, text}] }).
# All pages by default; --pages limits it ("3", "1-4", "1,3,7-9").
node .opencode/skills/pdf-tools/assets/pdf-agent.mjs text "<file.pdf>" --pages 1-4

# Sticky notes + highlight rectangles (plan JSON on stdin). Writes <base>.annotated.pdf.
echo '<plan-json>' | node .opencode/skills/pdf-tools/assets/pdf-agent.mjs annotate "<file.pdf>" --plan -

# Fill AcroForm fields from JSON key/values (stdin). Writes <base>.filled.pdf.
echo '{"Field Name":"value","Agree":true}' | node .opencode/skills/pdf-tools/assets/pdf-agent.mjs fill "<file.pdf>" --data -

# Stamp a signature block. Writes <base>.signed.pdf.
node .opencode/skills/pdf-tools/assets/pdf-agent.mjs sign "<file.pdf>" --name "Jane Doe" --date 2026-07-01
node .opencode/skills/pdf-tools/assets/pdf-agent.mjs sign "<file.pdf>" --name "Jane Doe" --image signature.png --page 3 --x 320 --y 90

Coordinates: pages are 1-based; x/y are PDF points (1/72 inch, US Letter is 612×792) with the origin at the BOTTOM-LEFT of the page; (x, y) is the bottom-left corner of the note/highlight/signature. Get each page's size from inspect before placing anything.

Annotate — the plan

{
  "annotations": [
    { "type": "note",      "page": 2, "x": 400, "y": 500, "text": "Cap is low for this deal — propose EUR 75k." },
    { "type": "highlight", "page": 2, "x": 70,  "y": 512, "width": 300, "height": 14 }
  ]
}

• note draws a yellow sticky note (text wraps automatically); text is required.
• highlight draws a translucent box over existing text; width is required, height defaults to 14 (one text line).
• Optional color is "#RRGGBB". A bad page/coordinate fails with a clear error instead of writing a broken file.

Fill-form

inspect first — fill by the exact name it reports. Values by field type: text takes any string, checkbox takes true/false, dropdown / option-list / radio-group take one of the listed options (anything else is skipped with the valid options in the reason). The result lists filled and skipped (each skip has a reason) — report skips and retry with corrected names/options rather than dropping them.

Sign

--name is required; --date defaults to today. Default placement is the bottom-right of the LAST page — pass --page/--x/--y to place it elsewhere (e.g. on the signature line inspect showed you). With --image sig.png the PNG is drawn above the signature rule instead of the typed name (--image-width scales it, default 140pt). This is a visible signature stamp, not a cryptographic signature.

Read (text)

To answer questions about a PDF, quote it, summarize it, or compare it against another document, run text and work from the returned per-page JSON — cite the page numbers it gives you. A scanned/image-only PDF has no text layer: pages come back empty. Say so plainly (offer annotation instead); never fabricate content.

Workflow

1. Resolve the target PDF (attached, @path, named, or in a folder). If the user points at a scan, remember highlights cover images fine, but form-fill needs real AcroForm fields — inspect reports fields: [] for flat PDFs; say so and offer annotations instead.
2. inspect and read the JSON: page sizes for placement, field names/options for filling. To read the document itself, run text.
3. Run the action (annotate / fill / sign). The tool refuses to overwrite the source; output goes to <base>.annotated.pdf / .filled.pdf / .signed.pdf next to it (--out to change).
4. Hand back: state the output file by the name the tool returns (a plain, space-free filename — this is what makes it appear as a clickable PDF artifact in the panel). Tell the user to open it in the in-app PDF viewer, summarize what you did, and flag any skipped entries with their reasons.

Guardrails

• Non-destructive. Never modify the source PDF in place; there is deliberately no --in-place.
• Never fabricate form values, names, or dates — ask when a value is missing.
• Encrypted/broken PDFs fail with a clear message; relay it, don't work around it.
• Distribution. Bundled-core: seeded into every workspace via core-skills.ts (scripts/gen-core-skills.mjs), alongside the in-app PDF viewer it feeds.