pdfnative MCP — PDF generation, PAdES signing & introspection

pdfnative-mcp

MCP server for PDF generation, PDF/A archival, PDF/X-4 print exchange, spot colours, right-to-left and 32-script text, JPEG 2000, fine typography, PAdES signing with long-term validation, AcroForms, merge/split, encryption and layout preview — 28 tools and 7 prompts on the pdfnative engine (zero-dependency, ISO 32000-1 compliant), for Claude Desktop, Cursor, ChatGPT and any Model Context Protocol client.

[npm version] [npm downloads] [Node version] [License: MIT] [CI] [MCP] [pdfnative] [TypeScript] [OpenSSF Scorecard] [CodeQL] [Fuzz] [MCP Registry]

✨ Features

pdfnative-mcp exposes 28 production-grade tools to any MCP host:

New in v1.8.0:

• 🎨 Spot colours — print.spotColours declares inks with a process alternate; { spot, tint } (a /Separation plate) and { inks: { … } } (a /DeviceN mix) are accepted wherever a colour is — table borders, templates, watermarks, charts, SVG, annotations. An undeclared ink is refused by name.
• ↔️ Right-to-left documents — direction: 'auto' | 'ltr' | 'rtl' on the nine document tools, inspect_layout and each paragraph; untagged output carries /ActualText on right-to-left and reordered shaped runs (actualText: false to opt out), so extract_text returns reading order with or without a PDF/A claim.
• 🌏 32 Unicode scripts — add_international_text gains gu (Gujarati), pa (Gurmukhi), kn (Kannada), ml (Malayalam) and or (Odia); every shaper names its glyphs in ToUnicode, so Tai Tham passes PDF/A-2u too.
• 🖼️ JPEG 2000 — mimeType: 'image/jp2' (a JP2 file or a raw codestream) on embed_image, the image block and image watermarks, embedded as /JPXDecode without re-encoding; PDFA1_JPX_IMAGE under PDF/A-1, PDFA_JPX_IMAGE for an opacity channel.
• 🖨️ PDF/X-4 + PDF/A-2 dual claim — pdfx: 'pdfx4' combines with pdfA: 'pdfa2b' | 'pdfa2u' in one file; pdfa1b and pdfa3b are refused with the engine's own message.
• 🔗 Link annotations — annotate_pdf type: 'link' adds a /URI link to an existing page (http: / https: / mailto:).
• 🔤 Operator fonts — PDFNATIVE_MCP_FONT_DIR registers the operator's .ttf / .otf files at boot (parsed by the engine, ≤ 64 files); font: '<slug>' on generate_basic_pdf, inspect_layout and add_international_text draws that face first — FONT_NOT_FOUND lists the slugs. See docs/guides/FONTS.md.
• 🌐 File mode behind a reverse proxy — PDFNATIVE_MCP_OUTPUT_BASE_URL maps the sandbox to a public base URL: file-mode results carry url and name it instead of the host's path (issue #66); pure string formatting, never requested.
• 📊 Charts — series[].colors (one colour per bar) and an optional series label ("Series N" otherwise).
• 🔏 LTV, ECDSA — add_ltv mode: 'offline' composes /DSS + /VRI through the engine (match: 'all' | 'chain'); verify_pdf verifies ECDSA through the engine's ecdsaVerifyHash (the local P-256 code is gone).
• 📖 extract_text — a content stream over the decompression cap is now PDF_PARSE_FAILED naming the remedy (onStreamError: 'skip' restores the 1.7.0 empty page); inspect_pdf decodes /Info text strings (UTF-16BE titles read back as text).
• 🤝 Governance as resources — pdfnative://governance/policy and pdfnative://governance/rules serve the AI-governance contract byte-identical to the repository (always listed); 13 engine diagnostics (4 new), 48 error codes (FONT_NOT_FOUND), prepare_signature_placeholder.blocks takes 5000 items like generate_basic_pdf (llama.cpp grammar, issue #65); calls carrying password are never cached.
• 🧪 Hardening — the pdfnative 1.9 release pipeline (guard → build → publish → attest → registry: Trusted Publishing, SHA-512-pinned npm client, registry bytes attested with three SBOMs, server.json published to the MCP registry with the workflow's OIDC identity), ClusterFuzzLite over five boundary targets, workflow-lint (zizmor + actionlint) as a required check, block-mode egress on the Linux jobs whose hosts are baselined (audit mode with a dated reason elsewhere), CodeQL on the workflows, Node 26 advisory, a pack-manifest gate step, every Dependabot and code-scanning alert of the 1.7.0 line closed. Catalogue: tools/list ≈ 357 kB under a 384 KiB budget.
• ⬆ Engine upgrade — pdfnative v1.9.0. No breaking change to the tool API; the bytes that change (lean compact subsets, /ActualText spans, one text object per line) are declared in the release note and the sample baseline is re-anchored once.

New in v1.7.0:

• 🔤 Fine typography — an opt-in typography object on the nine document tools and on inspect_layout: splitParagraphs with orphans / widows, keepHeadingsWithNext, unitBinding, bindShortWords, punctuationSpacing ('fr', 'fr-CA' or explicit rules), opticalMargins, metrics: 'exact', fontFeatures (11 OpenType tags), kerning, hyphenationLanguage. Paragraph blocks gain align (left / right / center / justify), keepWithNext and splittable; heading blocks gain keepWithNext. Honest limits: kerning, fontFeatures and the 'fr' narrow no-break space need embedFonts: true (base-14 Helvetica degrades 'fr' to 'fr-CA'); tnum / lnum change nothing on the bundled Noto Sans (diagnostic TYPOGRAPHY_FEATURE_INEFFECTIVE); no hyphenation dictionary is installed, so hyphenationLanguage has no effect here — soft hyphens (U+00AD) are honoured. See docs/guides/TYPOGRAPHY.md.
• 🎨 CMYK everywhere a colour is accepted — 'c m y k' operand strings (0–1) and [c, m, y, k] percent tuples (0–100) beside the existing hex / RGB forms: watermarks, header / footer templates, table cell borders, outline entries, charts, link and svg blocks, annotate_pdf. Every 1.6.0 colour form still validates.
• 🖨️ PDF/X-4 — pdfx: 'pdfx4' on six generation tools (generate_basic_pdf, add_table, add_chart, add_barcode, embed_image, add_international_text), CMYK or Gray outputIntent profiles beside RGB, print.marks.colourBars, and validate_pdf { standard: 'pdf-x-4' } to check the result; inspect_pdf reports the claim (pdfX, check 'pdfx'). It requires the printer's ICC profile (device class prtr — none is bundled), needs embedFonts: true for a conformant file (PDFX_NO_FONT_ENTRIES otherwise; strict: true refuses), and combines with pdfA: 'pdfa2b' | 'pdfa2u' since v1.8.0 (pdfa1b / pdfa3b and encrypt refused). The validation is structural — not a certified preflight; the result says so itself in caveats[]. See docs/guides/PRINT.md.
• 🌏 27 Unicode scripts — add_international_text accepts lo (Lao), nod (Tai Tham), khb (New Tai Lue), tdd (Tai Le) and cjm (Cham); ha, yo, ig, sw are aliases of latin (tone marks attach); emoji skin-tone modifiers render. Tai Tham under PDF/A must use pdfa2b, not pdfa2u (one glyph lacks a ToUnicode entry upstream).
• 🔁 Reproducible on every host — every date is written in UTC, {date} in a header or footer follows the pinned instant, and the operator can pin the whole process with PDFNATIVE_MCP_CREATION_DATE or SOURCE_DATE_EPOCH (see Environment variables). Not covered, by design: signingTime, modDate, RFC 3161 tokens and revocation data, encryption, ECDSA signatures. See docs/guides/REPRODUCIBLE.md.
• 🚦 strict escalates by diagnostic code — PDFA_* → PDF_A_COMPLIANCE_VIOLATION, PDFX_* → PDF_X_COMPLIANCE_VIOLATION (new), anything else → DIAGNOSTIC_ESCALATED (new). Both new codes can only be returned by a call that sets strict: true.
• 🧩 A seventh MCP prompt, typography — and print_ready, reproducible_output, pdfa_valid rewritten for CMYK, PDF/X-4, colour bars and the UTC / operator pin.
• 🐛 Fixes — a 0–1 RGB triple (watermark.color, the annotate_pdf colours) now renders the colour it names ([1, 0, 0] used to render almost black); any unexpected failure of a tool that takes PDF input is classified PDF_PARSE_FAILED instead of surfacing uncoded.
• ✅ Closed upstream — a PDF/A form built with embedFonts: true now validates under veraPDF (the AcroForm font is embedded), and inspect_layout measures a toc block exactly as the build lays it out.
• 🧪 One gate, hardened CI, verified docs — npm run gate is the single definition of green (the built server is driven over stdio and stdout must carry JSON-RPC frames only); veraPDF is blocking over a 41-file conformance corpus; a 96-sample byte baseline guards the output; npm run verify:docs holds every count, version, tool, error code and operator variable quoted in the docs to docs/assets/ecosystem.json and the source tree.
• 🧾 Catalogue — tools/list grows to ≈ 306 kB in 1.7.0 (the typography fragment and the widened colour schemas are inlined in every tool that carries them; npx tsx scripts/tool-shape.ts --check held it under 320 KiB and the instructions under 8 KiB); _meta.apiVersion is 1.7.0.
• ⬆ Engine upgrade — pdfnative v1.8.0. No breaking change to the tool API; the bytes that do change (embedded TrueType subsets, print.marks, shaped text with mark positioning, UTC dates) are listed under Upgrade in release-notes/v1.7.0.md.

New in v1.6.0:

• 🧱 Full engine coverage — 13 block kinds — generate_basic_pdf accepts every DocumentBlock pdfnative offers: the new table, image, link, toc, barcode, svg and formField blocks share their body with the dedicated tools (add_table, embed_image, add_barcode, add_form) so a standalone artefact and an inline block validate and render identically. Rules: link accepts http: / https: / mailto: only (control characters rejected); image blocks are bounded (12 M base64 characters each, 24 MiB decoded per call; PNG must be 8-bit, non-interlaced, without alpha or palette — rejected with a remedy); svg covers paths, basic shapes and <text> (no transform, <g>, gradients or CSS — silently ignored; nothing is ever fetched); toc pairs with outline: 'auto'; formField under a PDF/A claim reports PDFA_UNEMBEDDED_FORM_FONT; barcode has no alt (engine limitation).
• 📐 Layout options on the nine document tools — pageSize (A4 default, Letter, Legal, A3, Tabloid), margins (all four, 0–200 pt), headerTemplate / footerTemplate with {page} {pages} {title} {date} (a footerTemplate replaces the default footer, so footerText is then ignored; {date} was the build-day wall clock in 1.6.0 — since v1.7.0 it follows the pinned instant), compress (FlateDecode streams — smaller file, different bytes; XMP stays plain under PDF/A) and debug (guide rectangles, unmarked content — not for PDF/UA). Absent by default, so default output stays byte-identical.
• 🔐 Encryption at build time — encrypt on seven document tools (generate_basic_pdf, add_table, add_form, add_international_text, embed_image, add_barcode, add_chart): Standard Security Handler, AES-128 default / AES-256, keeps the AcroForm (unlike encrypt_pdf, which rebuilds the page tree). Exclusive with pdfA (VALIDATION_ERROR), never cached; not offered on prepare_signature_placeholder (must stay signable) or add_attachment (PDF/A-3).
• 📏 inspect_layout — the 28th tool: a read-only pagination dry run over the same blocks and layout inputs, reporting totalPages and each block's page / x / top / width / height without rendering a PDF. Known engine gap in 1.6.0 (closed in v1.7.0): a toc block was measured as 0 pt, so documents with a printed contents could paginate one page later than previewed.
• 🔎 inspect_pdf annotations: true — lists every page annotation (subtype, 0-based page, rect, contents truncated to 200 chars, title, colour, quadPoints, link URL) plus annotationCount; new check: 'annotations'.
• 🖼️ Image watermarks — watermark.image (JPEG/PNG, default opacity 0.10, own 8 MiB cap) on generate_basic_pdf and add_table, alone or combined with text (default opacity 0.15); position: 'background' | 'foreground' for both. Either opacity below 1.0 is rejected under pdfa1b.
• 🧯 PDFNATIVE_MCP_MAX_INFLATE_BYTES — operator override of the engine's 100 MiB per-stream decompression cap (integer ≥ 1024; an invalid value refuses to start). A capped attachment stream fails extract_attachments includeData: true with PDF_PARSE_FAILED; extract_text degrades to empty page text (the engine swallows per-page decode failures).
• 📝 Forms — add_form and formField blocks gain listbox and placeholder; fieldType: 'textarea' now reaches the engine as multilineText (it was passed through unmapped before and rendered as a single-line field — a bug fix that changes bytes for that input). embed_image gains align and alt.
• 🔏 PAdES long-term validation ladder — sign_pdf gains profile: 'pades' (ETSI EN 319 142-1 baseline, ESS signing-certificate-v2, ETSI.CAdES.detached), timestamp: true (B-T, RFC 3161), RSA-SHA384/512, certChainDerBase64, fieldName / allowMultiple for several signatures; new add_ltv embeds a /DSS (B-LT, mode: 'online' through the operator provider or mode: 'offline' with caller-supplied DER material); new timestamp_pdf appends a /DocTimeStamp (B-LTA). verify_pdf ltv: true reports profile, timestamp, revocation status and ltvLevel. See docs/guides/LTV.md.
• 🌐 Network charter — no outbound request by default. The only egress the server can ever perform goes to the RFC 3161 / OCSP / CRL endpoints the operator configured (PDFNATIVE_MCP_TSA_URL, PDFNATIVE_MCP_REVOCATION, PDFNATIVE_MCP_NETWORK_ALLOWED_HOSTS), behind an SSRF guard; tool arguments can never supply a URL.
• 🖨️ Print production — every document tool accepts print (TrimBox / BleedBox / ArtBox / CropBox or the bleed shorthand, crop + registration marks, /UserUnit), metadata (/Author, /Subject, /Keywords, /Trapped) and outputIntent (custom RGB ICC for PDF/A); viewerPreferences gains duplex, pickTrayByPDFSize, printPageRange, numCopies. inspect_pdf pages: true reports the boxes; merge / split / extract preserve them. See docs/guides/PRINT.md.
• ✍️ update_metadata — rewrite /Info + XMP of an existing PDF as an incremental update (earlier revisions and signatures preserved verbatim).
• 📊 Charts v2 — stackedBar / stackedBarH / area / scatter, secondary right axis (axis2), axis.scale: 'log', xAxis.type: 'linear' | 'time', dataLabels, labelStride / labelRotation; overlapping category labels are thinned automatically.
• 📜 Honest PDF/A — embedFonts: true embeds Noto Sans Latin (base-14 Helvetica is not embedded, so a PDF/A claim on plain Latin text is rejected by veraPDF), strict: true fails instead of producing a non-conformant file, includeDiagnostics: true echoes engine diagnostics. Local veraPDF script (npm run validate:pdfa) over a 26-file corpus (24 validated, 3 of them negative canaries; 2 page-tree outputs skipped) and a fail-closed VERAPDF_REQUIRED=1 mode; the CI workflow pins the installer by SHA-256 and stays non-blocking in 1.6.0 (blocking since v1.7.0, where --require-all on the gate replaces VERAPDF_REQUIRED=1). Known engine gaps in 1.6.0: add_form output fails PDF/A-2b even with embedFonts (unembedded /DR /Helv — closed in v1.7.0), and a prepare_signature_placeholder output is conformant only once signed.
• 🧰 inspect_pdf — signatures: true inventory, dss / docTimestampCount / trapped (presence-gated), new check values dss, docTimestamp, trapped; checks lists only the keys you requested, and signed is structural (a signed field exists — validity is verify_pdf's job).
• 🔁 Reproducible output — opt-in creationDate on all nine document tools pins /CreationDate, the XMP dates and the trailer /ID; signingTime on prepare_signature_placeholder (and on sign_pdf, now with time-zone offsets) pins /Sig /M. Identical bytes on the same host time zone in 1.6.0 (on every host since v1.7.0: dates are written in UTC). Backed by the reproducible_output prompt.
• 🛡️ Hardened boundary — strict input schemas (unknown or misspelt keys → VALIDATION_ERROR instead of being silently ignored); data:…;base64, prefixes tolerated, PEM-where-DER and double-encoded payloads rejected with the exact remedy; page-index mistakes on the page-tree tools are VALIDATION_ERROR with a 0-based hint; an unknown tool name is a JSON-RPC protocol error (-32602, [UNKNOWN_TOOL]).
• 🔑 HTTP bearer token — opt-in PDFNATIVE_MCP_HTTP_TOKEN gates the Streamable HTTP endpoint (401 + WWW-Authenticate otherwise). Without it the loopback endpoint has no authentication — see SECURITY.md.
• 🧾 Catalogue — tools/list is ≈ 245 kB (1.5.0: ≈ 108 kB) because every block kind, layout option and encrypt fragment is now advertised inline — no $ref / $defs by policy, so hosts that forward inputSchema to function-calling APIs never meet a reference; the server instructions are ≈ 6.7 kB (from 12.9 kB). Structure is guarded by scripts/tool-shape.mjs (scripts/tool-shape.ts since v1.7.0) + tests/catalogue-parity.test.ts, and tests/catalogue-superset.test.ts proves the live catalogue is a superset of the published 1.5.0 one; at most two executable _meta.examples per tool, the rest under examples/. Four new recipe prompts: pades_ladder, print_ready, reproducible_output, pdfa_valid.
• 🐛 Fixes — signer metadata (signerName / reason / location / contactInfo) never reached the /Sig dictionary on pdfnative < 1.7; it is now baked at placeholder time. verify_pdf no longer reports allValid: false on B-LTA documents (a /DocTimeStamp was parsed as a CMS signature).
• 🔌 MCP 2026-07-28 on the MCP TypeScript SDK v2 (@modelcontextprotocol/server) with automatic fallback to the 2025-era initialize handshake — existing hosts keep working unchanged. See MCP protocol compliance.
• ⬆ Engine upgrade — pdfnative v1.7.0 (LTV, print production, charts v2, digest agility, flag / ZWJ emoji sequences, UAX #9 fixes).

New in v1.5.0:

• 📊 Native vector charts — add_chart renders bar / horizontal-bar / line / pie / donut charts as pure PDF path operators (zero rasterisation, PDF/A-safe with auto alt text). generate_basic_pdf also accepts a chart block for composition with text and tables.
• 📝 Fill & flatten forms — read_form_fields lists an existing AcroForm's fields; fill_form fills and/or flattens it via a non-destructive incremental update (the counterpart to add_form).
• 🔐 Encryption round-trip — encrypt_pdf re-secures with AES-128 / AES-256 (RC4 never emitted), decrypt_pdf recovers an unencrypted copy, a password input opens encrypted sources on the read-only tools, and merge_pdfs / split_pdf / extract_pages gain password + encrypt.
• 🔤 Real text extraction — extract_text now resolves each font's /ToUnicode CMap (no more glyph-index output) and can return positioned runs.
• 🔗 Native MCP resources — sandboxed generated PDFs become pdfnative://output/… resources (resources/list + resources/read), with a resource_link in file-mode results for cross-call re-reference.
• 🏷️ Tool annotations — every tool advertises readOnlyHint / destructiveHint / idempotentHint / openWorldHint.
• ⬆ Engine upgrade — pdfnative v1.6.0 (decrypt/re-encrypt, extractText, fill/flatten, charts; colour-emoji subset 221 → 1167 glyphs).

New in v1.4.0:

• 🤝 AI governance + human-in-the-loop — draft_governance_issue lets an agent draft a fully compliant GitHub issue locally (draft .md + machine-readable compliance report). The agent is a draftsman, never an autonomous submitter: a human is the only gate, and the server makes zero GitHub writes (and, since v1.6.0, no outbound call other than to operator-configured TSA / OCSP / CRL endpoints). Backed by the governance_contract and draft_issue_workflow MCP prompts.
• ✏️ Markup annotations — annotate_pdf overlays highlight, sticky-note, underline, strikeout, squiggly, square, circle, line, and freetext annotations on an existing PDF via incremental update. It is a visual review layer, not a redaction — underlying bytes remain.
• 🔢 Page labels in inspect_pdf — read-only surfacing of /PageLabels ranges (roman, decimal, prefixed).
• ∑ Math / scientific script — add_international_text accepts lang: 'math' (explicit, like emoji) to embed the Noto Sans Math face on demand.
• 🧩 MCP prompts — the server now advertises the prompts capability with governance_contract and draft_issue_workflow.
• ⬆ Engine upgrade — pdfnative v1.5.0.

New in v1.3.0:

• 🆕 Three page-tree tools — merge_pdfs, split_pdf, extract_pages (built on pdfnative v1.4.0's page-tree API; encrypted sources were rejected until v1.5.0 added password).

• 🔖 Bookmarks, page labels & nested lists — generate_basic_pdf gains outline ('auto' or explicit tree), pageLabels, multi-level list items, and viewerPreferences.

• 📐 Table cell borders & alignment — add_table gains cellBorders, cellVAlign, and viewerPreferences; add_international_text gains viewerPreferences.

• 🔐 Constant-time signing — sign_pdf signs RSA and EC-DER keys through a node:crypto provider with a transparent pure-JS fallback (raw P-256 scalars stay pure JS, and verification is pure JS); signatures stay interoperable.

• ⬆ Engine upgrade — pdfnative v1.4.0.

• 🆕 Tool extract_attachments — read embedded files back out of a PDF (completes the Factur-X / ZUGFeRD round-trip) with byte-for-byte payloads, a filename filter, and an includeData: false metadata-only probe.

• 💧 Watermarks — generate_basic_pdf and add_table accept an optional watermark (text, opacity, angle, colour, position; image since v1.6.0) rendered on every page.

• 🌐 Unicode normalize — opt-in NFC/NFD/NFKC/NFKD on generate_basic_pdf and add_international_text.

• 🪙 Token-frugal reads — the read-only tools (inspect_pdf, verify_pdf, validate_pdf, extract_text, extract_attachments; read_form_fields since v1.5.0) accept optional verbosity: 'summary' and fields: […] inputs for ~90% smaller responses on large results, with no loss of the fields agents branch on. Defaults are unchanged.

• 🪙 No base64 duplication — generated PDFs (base64 mode) are returned once as an embedded resource content block instead of also being copied into structuredContent.

• 🔧 MCP registry publish fix — mcpName now uses the canonical GitHub login casing (io.github.Nizoka/pdfnative-mcp) so the registry's case-sensitive validation accepts the npm package.

• ⬆ Dependency — upgraded to zod 4.

New in v1.1.0:

• 🆕 Tool validate_pdf — read-only PDF/UA (ISO 14289-1) structural conformance check.
• 🆕 Six new scripts — Telugu, Sinhala, Tibetan, Khmer, Myanmar, Ethiopic (24 scripts total).
• 🆕 COLRv1 colour emoji — native colour emoji with monochrome fallback.
• 🆕 Newline sanitizer — embedded \n in paragraphs auto-splits into separate paragraphs (Safe PDF/A).
• 🆕 Automatic NFC normalisation for add_international_text.
• 🛠 Engine upgrade — pdfnative v1.3.0: the Euro sign / CP-1252 symbols now extract correctly, and wrapped table cells get unique per-line MCIDs (PDF/UA-safe).

New in v1.0.0:

• 🆕 Three new tools: verify_pdf, add_attachment (Factur-X / ZUGFeRD), extract_text.
• 🆕 Smart-table fields: wrap, repeatHeader, zebra, caption, minRowHeight, cellPadding.
• 🆕 inspect_pdf now reports hasSignaturePlaceholder and per-attachment summary; new check values 'placeholder' and 'attachments'.
• 🆕 Signing ergonomics: sign_pdf accepts ECDSA SEC1 / PKCS#8 DER keys and auto-injects a /Sig placeholder when missing (one-call signing of any PDF).
• 🆕 Opt-in cache (PDFNATIVE_MCP_CACHE_DIR): SHA-256 keyed, 1 h TTL, 256 MiB LRU.
• 🆕 _meta.apiVersion and per-tool _meta.examples for AI-agent discovery — see docs/API_STABILITY.md.
• 🆕 AI agent guide: docs/AI_GUIDE.md — decision tree + common pitfalls. See also the agent contract, docs/AGENT_CONTRACT.md (catalogue, decision tree, recipes, error table); contributors and coding agents start at AGENTS.md.
• 🆕 PDF/A authoring guide: docs/guides/PDFA.md.
• 🛠 Env-var rename: PDFNATIVE_MCP_OUTPUT_DIR (was PDFNATIVE_MPC_OUTPUT_DIR; old name still works with a one-shot deprecation warning).
• ✅ Now shipped: merge_pdfs, split_pdf, extract_pages (v1.3.0), annotate_pdf (v1.4.0), the add_chart / read_form_fields / fill_form / encrypt_pdf / decrypt_pdf tools plus the encrypted round-trip and native MCP resources (v1.5.0), and add_ltv / timestamp_pdf / update_metadata plus print production and charts v2 (v1.6.0). redact_pdf stays deferred — pdfnative can overlay/flatten but not remove page content, and an overlay-only "redaction" would create false security, so it is intentionally not shipped (tracked as an upstream content-removal request).

All tools support two output modes:

• base64 (default) — the generated PDF is returned once as an embedded resource content block (a data:application/pdf;base64,… URI); structuredContent carries only { mode, sizeBytes } (plus diagnostics[] when includeDiagnostics: true, and a summary for add_ltv).
• file — the PDF is written to a sandboxed directory configured via PDFNATIVE_MCP_OUTPUT_DIR. File output is disabled unless this variable is set; absolute paths, path traversal, non-.pdf extensions, and NUL bytes are all rejected.

Upgrading from v1.1.0: the only behaviour change is that base64-mode bytes are no longer duplicated into structuredContent.base64. Read them from the embedded resource block instead:

diff

- const base64 = response.structuredContent.base64;   // v1.1.0+ const block = response.content.find((c) => c.type === 'resource');+ const base64 = block.resource.blob;                  // v1.2.0

Token-frugal reads (v1.2.0). The seven read-only tools (inspect_pdf, verify_pdf, validate_pdf, extract_text, extract_attachments, read_form_fields, inspect_layout) accept two optional inputs:

• verbosity: 'summary' — returns a compact scalar-only verdict (drops the heavy arrays / full text). E.g. verify_pdf → { signatureCount, allValid, invalid, summary } (+ ltvLevel with ltv: true); inspect_pdf keeps docTimestampCount / trapped / checksPassed when present.
• fields: ['a', 'b.c'] — projects the structured result to named dot-paths; composes after verbosity. Unmatched paths are omitted and reported in _meta.unmatchedFields (with _meta.availableFields).

Smallest “is this PDF signed and valid?” probe: { "pdfBase64": "…", "verbosity": "summary", "fields": ["allValid"] }.

Why pdfnative?

pdfnative-mcp inherits every guarantee of the underlying engine:

• Zero runtime dependencies in the engine — pure JavaScript, no native bindings (this server adds only the MCP SDK and zod: three runtime dependencies in total).
• ISO 32000-1 (PDF 1.7) compliant output.
• PDF/A-1b/2b/2u/3b, AES-128/256 encryption, AcroForm, digital signatures.
• 32 Unicode scripts (39 lang codes incl. latin, emoji, math and the four latin aliases) with built-in BiDi reordering, Arabic positional shaping, Indic / Thai OpenType shaping and, since v1.8.0, a base text direction (auto / ltr / rtl) for right-to-left documents.
• PDF/X-4 print exchange, DeviceCMYK colour and fine typography (orphan / widow control, justification, French punctuation spacing, OpenType features).
• Tree-shakeable ESM build.

🚀 Installation

# Run directly with npx (recommended for MCP clients)npx -y pdfnative-mcp
# Or install globallynpm install -g pdfnative-mcppdfnative-mcp

Requirements: Node.js ≥ 22.

⚙️ Configuration

Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{  "mcpServers": {    "pdfnative": {      "command": "npx",      "args": ["-y", "pdfnative-mcp"],      "env": {        "PDFNATIVE_MCP_OUTPUT_DIR": "/Users/you/Documents/mcp-pdfs"      }    }  }}

Cursor / Continue / Zed / Windsurf / Cline / Roo Code

Any MCP-compatible client that supports stdio servers will work. Use the same command + args + env triple. Example for Cursor (~/.cursor/mcp.json):

{  "mcpServers": {    "pdfnative": {      "command": "npx",      "args": ["-y", "pdfnative-mcp"],      "env": { "PDFNATIVE_MCP_OUTPUT_DIR": "/Users/you/Documents/mcp-pdfs" }    }  }}

Windsurf / Cline / Roo Code use the same shape inside their respective MCP config files.

🌐 Supported AI Ecosystem & Clients

pdfnative-mcp is designed for MCP-native environments and works with clients that support MCP over stdio or Streamable HTTP.

Community-verified compatibility includes:

• Ontheia — a self-hosted, open-source AI agent platform (privacy-first). Reported as working out of the box in issue #41 and listed on Ontheia's compatible MCP servers page.

🔌 MCP protocol compliance

Since v1.6.0 the server is built on the MCP TypeScript SDK v2 (@modelcontextprotocol/server) and speaks MCP 2026-07-28:

• Stateless serving — server/discover replaces the session handshake; every result carries resultType and the _meta serverInfo envelope. Over HTTP, 2026-07-28 clients send Mcp-Method / Mcp-Name headers with each POST /mcp.
• Cache hints — tools/list and prompts/list are public with a 24 h ttlMs, server/discover is public for 1 h, and resources/list / resources/templates/list / resources/read are private with ttlMs: 0 (generated PDFs are per-host user data).
• Resource errors — an unknown resource URI is reported as JSON-RPC -32602 (Invalid params), as the 2026-07-28 specification requires.
• Automatic legacy fallback — a client that opens with initialize (2025-11-25, 2025-06-18 or 2025-03-26) is served through the SDK's legacy path on both stdio and HTTP. Nothing changes for existing hosts.
• HTTP — GET / DELETE /mcp answer 405 (no SSE resumability; the server is stateless). The loopback bind and the Host / Origin guard are unchanged, and the Origin port must now equal the server port (the SDK check alone is port-agnostic); PDFNATIVE_MCP_HTTP_TOKEN adds an opt-in bearer-token gate (401 + WWW-Authenticate without it). JSON-RPC batch arrays (2025-03-26) are accepted over HTTP. Keep-alive connections no longer accumulate socket listeners.
• stdio — as in every SDK release to date, a request sent before initialize is dropped without a reply and JSON-RPC batch arrays are not accepted on stdio (unchanged from 1.5.0; no major host batches).
• Protocol errors — tools/call with an unknown tool name is a JSON-RPC error (-32602, [UNKNOWN_TOOL] Unknown tool: …) rather than an isError result, as the specification classifies it; isError: true is reserved for execution failures.
• Output schemas — every structuredContent validates against the tool's outputSchema (a 2026-07-28 MUST), including verbosity: 'summary' and fields projections: the seven read tools declare projectable schemas (all properties optional, additionalProperties: false kept). Input schemas carry no $schema keyword by policy (MCP ≥ 2025-11-25 defaults to JSON Schema 2020-12; some hosts forward inputSchema to function-calling APIs that reject unknown keywords). serverInfo carries websiteUrl; the resource template is pdfnative://output/{+path}.

The tools/call payload (content, structuredContent, isError) is identical between the 2026-07-28 path and the legacy path; tests/http-modern.test.ts asserts it, and tests/schema-conformance.test.ts validates structuredContent with the SDK's JSON Schema 2020-12 validator.

Environment variables

Creation-date precedence (highest first): the per-call creationDate → PDFNATIVE_MCP_CREATION_DATE → SOURCE_DATE_EPOCH → the wall clock. Dates are always written in UTC, so pinned output is byte-identical on every host and in every time zone. The pin does not cover, by design: signingTime (sign_pdf, prepare_signature_placeholder), modDate (update_metadata), the regenerated second /ID of incremental writers (annotate_pdf, fill_form), RFC 3161 timestamp tokens and online revocation data, encryption (fresh file key, salts and IVs) and ECDSA signatures (randomised by design). See docs/guides/REPRODUCIBLE.md.

🛠 Tool reference

generate_basic_pdf

{  "title": "Q1 2026 Report",  "blocks": [    { "type": "heading", "text": "Executive summary", "level": 1 },    { "type": "paragraph", "text": "Revenue grew 24% year over year." },    { "type": "list", "style": "bullet", "items": ["Strong APAC", "Stable EU", "Soft NA"] },    { "type": "pageBreak" },    { "type": "heading", "text": "Details", "level": 2 }  ],  "footerText": "Confidential — Internal use only",  "outputMode": "base64"}

The 13 block kinds: heading, paragraph, list, table, image, link, toc, barcode, svg, formField, chart, pageBreak, spacer. A composite report:

{  "title": "Quarterly report",  "blocks": [    { "type": "toc" },    { "type": "heading", "text": "Sales", "level": 1 },    { "type": "table", "headers": ["Region", "Revenue"], "rows": [["EMEA", "1.2 M"], ["APAC", "0.9 M"]], "zebra": true },    { "type": "image", "imageBase64": "<base64 JPEG>", "mimeType": "image/jpeg", "width": 300, "alt": "Revenue chart" },    { "type": "svg", "data": "M10 10 H 90 V 90 H 10 Z", "viewBox": [0, 0, 100, 100], "fill": "#0a7e8c" },    { "type": "barcode", "format": "qr", "data": "https://example.com/q1", "align": "center" },    { "type": "link", "text": "Full dataset", "url": "https://example.com/data" },    { "type": "formField", "fieldType": "text", "name": "reviewer", "label": "Reviewed by" }  ],  "outline": "auto",  "pageSize": "Letter",  "headerTemplate": { "right": "{title} — page {page}/{pages}" },  "embedFonts": true}

Block rules: table, barcode, formField and chart take the same body as add_table / add_barcode / add_form / add_chart; link URLs must be http:, https: or mailto:; image blocks are capped at 12 M base64 characters each and 24 MiB decoded per call (PNG: 8-bit greyscale/RGB, non-interlaced, no alpha, no palette — otherwise VALIDATION_ERROR with a remedy); svg supports <path>, <rect>, <circle>, <ellipse>, <line>, <polyline>, <polygon>, <text>/<tspan> and silently ignores transform, <g>, <use>, <image>, gradients, opacity and CSS (no external reference is ever fetched); toc is built from the heading blocks and pairs with outline: 'auto'; formField under pdfA needs embedFonts: true so the field font is embedded too (PDFA_UNEMBEDDED_FORM_FONT otherwise; strict: true then fails); barcode has no alt. Use inspect_layout with the same inputs to preview the pagination before rendering.

Typography (v1.7.0). typography is one opt-in object (12 keys, all off by default — omitted means unchanged bytes) on the nine document tools and on inspect_layout:

{  "title": "Annual report",  "embedFonts": true,  "typography": {    "splitParagraphs": true, "orphans": 3, "widows": 3,    "keepHeadingsWithNext": { "minLines": 3 },    "opticalMargins": true, "kerning": true, "fontFeatures": ["onum", "smcp"],    "unitBinding": true, "bindShortWords": true, "punctuationSpacing": "fr"  },  "blocks": [    { "type": "heading", "text": "Outlook", "level": 2, "keepWithNext": true },    { "type": "paragraph", "text": "A long justified paragraph…", "align": "justify" },    { "type": "paragraph", "text": "Figures by region:", "keepWithNext": true, "splittable": false }  ]}

• Keys: splitParagraphs, orphans / widows (1–10, default 2, need splitParagraphs), keepHeadingsWithNext (true or { minLines }), unitBinding (true or { units }), bindShortWords (true or { maxLength, words }), punctuationSpacing ('fr', 'fr-CA' or an array of { char, side, space } rules), opticalMargins, metrics ('approximate' default / 'exact'), fontFeatures (tnum, pnum, lnum, onum, zero, ordn, sups, subs, smcp, c2sc, case), kerning, hyphenationLanguage.
• Block inputs: a paragraph takes align (left default / right / center / justify), keepWithNext and splittable (overrides typography.splitParagraphs for that block); a heading takes keepWithNext (overrides typography.keepHeadingsWithNext for that block).
• Limits: kerning, fontFeatures and the 'fr' narrow no-break space need an embedded font (embedFonts: true; on base-14 Helvetica 'fr' degrades to 'fr-CA'); metrics: 'exact' acts on base-14 text only; tnum / lnum change nothing on the bundled Noto Sans (diagnostic TYPOGRAPHY_FEATURE_INEFFECTIVE); no hyphenation dictionary is installed, so hyphenationLanguage has no effect on this server — soft hyphens (U+00AD) in the text are honoured. See docs/guides/TYPOGRAPHY.md and the typography prompt.

CMYK colours (v1.7.0). Every colour input keeps the form it has always accepted (hex on charts, templates, link and svg blocks; a 0–1 RGB triple on watermarks and annotate_pdf; a free string on outline entries and table cell borders) and gains DeviceCMYK beside it: an operand string 'c m y k' with components 0–1 ("1 0.6 0 0.1") and a percent tuple [c, m, y, k] with components 0–100 ([100, 60, 0, 10]). Under a PDF/A claim against the default sRGB intent a CMYK colour reports PDFA_DEVICE_CMYK_CONTENT — keep colours RGB there, or supply a CMYK outputIntent.

PDF/X-4 (v1.7.0). pdfx: 'pdfx4' on generate_basic_pdf, add_table, add_chart, add_barcode, embed_image and add_international_text writes a PDF/X-4 (ISO 15930-7) file: %PDF-1.6 header, the PDF/X-4 XMP identification, a /GTS_PDFX output intent, a TrimBox on every page and /Trapped.

{  "title": "Spring catalogue",  "pdfx": "pdfx4",  "embedFonts": true,  "outputIntent": { "iccProfileBase64": "<the printer's CMYK ICC profile, base64>", "outputConditionIdentifier": "FOGRA39" },  "metadata": { "trapped": "False" },  "print": { "bleed": 14.17, "marks": { "colourBars": true } },  "blocks": [{ "type": "paragraph", "text": "Four-colour job exchanged as PDF/X-4." }]}

• It requires outputIntent with the ICC profile of the printing condition (device class prtr, CMYK or Gray — no press profile is bundled; ask your printer); it needs embedFonts: true for a conformant file (PDFX_NO_FONT_ENTRIES otherwise; strict: true refuses); it combines with pdfA: 'pdfa2b' | 'pdfa2u' since v1.8.0 (one file, both claims; pdfa1b / pdfa3b refused) and is exclusive with encrypt; metadata.trapped must be 'True' or 'False'; a page carries a TrimBox or an ArtBox, not both. Incoherent requests are refused with VALIDATION_ERROR before any work is done. Links and form fields are reported (PDFX_ANNOTATIONS); with strict: true a PDFX_* diagnostic fails the call with PDF_X_COMPLIANCE_VIOLATION.
• outputIntent accepts RGB, CMYK and Gray profiles (≤ 8 MiB, under pdfA or pdfx). The profile must be a real ICC file (acsp signature, consistent size field) — a hand-made stub is rejected.
• print.marks accepts true or an object; marks.colourBars (true or { tints, size }, size 4–72 pt, default 12) adds the C M Y K solids and their 50 % tints in the bleed. Off by default; it needs a bleed of about 5 mm (14.17 pt) and is skipped when the strip would not fit.
• Check the result with validate_pdf { standard: 'pdf-x-4' } — a structural check, not a certified preflight. See docs/guides/PRINT.md and the print_ready prompt.

add_barcode

{  "format": "qr",  "data": "https://pdfnative.dev",  "caption": "Scan to learn more",  "ecLevel": "H",  "outputMode": "file",  "outputPath": "tickets/event-42.pdf"}

Supported formats: qr, code128, ean13, datamatrix, pdf417.

add_international_text

{  "title": "مرحبا بالعالم",  "lang": "ar",  "paragraphs": [    "هذا اختبار للنص العربي مع تشكيل OpenType ومحارف ثنائية الاتجاه.",    "Mixed content: العربية + English ✓"  ]}

Supported lang codes: the 32 Unicode scripts — ar, he, th, ja, zh, ko, el, hi, bn, ta, ru, ka, hy, tr, pl, vi, te, si, bo, km, my, am, and since v1.7.0 lo (Lao), nod (Tai Tham), khb (New Tai Lue), tdd (Tai Le), cjm (Cham), and since v1.8.0 gu (Gujarati), pa (Gurmukhi), kn (Kannada), ml (Malayalam), or (Odia) — plus the utility faces latin, emoji and math. Since v1.7.0 ha (Hausa), yo (Yoruba), ig (Igbo) and sw (Swahili) are aliases of latin: the bundled Noto Sans anchors their tone marks, no extra font is embedded. Fonts are always embedded (no embedFonts input); pin creationDate for byte-identical output. The tool also accepts typography and pdfx (see generate_basic_pdf).

Tai Tham under PDF/A: lang: 'nod' validates under pdfa2b and, since 1.8.0, under pdfa2u too — pdfnative 1.9.0 names every shaped glyph in ToUnicode (the 1.7.0 "use pdfa2b" rule is lifted).

Multi-script documents — pass an array or comma-separated list:

{  "title": "Mixed Script",  "lang": ["ar", "emoji"],  "paragraphs": ["العربية مع رموز 🎉🚀"],  "pdfA": "pdfa2u"}

sign_pdf

As of v1.0.0, sign_pdf auto-injects a /Sig placeholder when missing — you can sign any PDF in one call:

{  "pdfBase64": "<any base64 PDF>",  "algorithm": "rsa-sha256",  "certDerBase64": "<base64 X.509 cert in DER>",  "rsaKeyPkcs1DerBase64": "<base64 PKCS#1 RSAPrivateKey DER>",  "signerName": "Alice",  "reason": "Approval",  "location": "Paris, FR",  "signingTime": "2026-01-15T10:30:00Z"}

For ECDSA P-256: use algorithm: "ecdsa-sha256" and supply either ecPrivateKeyDerBase64 (SEC1 or PKCS#8 DER) or ecPrivateScalarHex (64 hex chars).

PEM → DER conversion:

openssl x509 -in cert.pem -outform DER | openssl base64 -A                 # certopenssl rsa  -in key.pem  -outform DER -traditional | openssl base64 -A    # RSA PKCS#1openssl pkey -in key.pem  -outform DER | openssl base64 -A                 # ECDSA

Use prepare_signature_placeholder only when you need to customize the placeholder (e.g. larger placeholderBytes for >4096-bit RSA keys, subFilter: 'ETSI.CAdES.detached', reserveTimestamp: true). Otherwise call sign_pdf directly.

PAdES ladder (v1.6.0). sign_pdf with profile: "pades" produces a B-B signature; add timestamp: true for B-T (needs PDFNATIVE_MCP_TSA_URL), then add_ltv (B-LT) and timestamp_pdf (B-LTA):

// 1. sign_pdf  { ..., "profile": "pades", "timestamp": true, "certChainDerBase64": ["<intermediate DER>"] }// 2. add_ltv   { "pdfBase64": "<signed>", "mode": "online" }            // or "offline" + certificatesDerBase64 / ocspResponsesDerBase64 / crlsDerBase64// 3. timestamp_pdf { "pdfBase64": "<ltv>" }                              // re-run before the TSA certificate expires// 4. verify_pdf { "pdfBase64": "<final>", "ltv": true }                  // -> ltvLevel: "B-LTA"

Signer metadata (signerName, reason, location, contactInfo) is baked into the placeholder; fieldName selects one of several unsigned placeholders (PLACEHOLDER_AMBIGUOUS otherwise) and allowMultiple: true adds a further signature. See docs/guides/LTV.md.

add_table

{  "title": "Monthly Sales",  "headers": ["Region", "Units", "Revenue"],  "rows": [    ["APAC", "1200", "$240,000"],    ["EMEA", "800", "$160,000"]  ],  "infoItems": [{ "label": "Period", "value": "January 2025" }],  "footerText": "Internal use only",  "outputMode": "base64"}

add_form

{  "title": "Employee Onboarding",  "fields": [    { "fieldType": "text", "name": "fullName", "label": "Full Name", "required": true },    { "fieldType": "dropdown", "name": "dept", "label": "Department", "options": ["Engineering", "Sales", "HR"] },    { "fieldType": "checkbox", "name": "agree", "label": "I agree to the terms", "checked": false },    { "fieldType": "listbox", "name": "skills", "label": "Skills", "options": ["TypeScript", "PDF", "MCP"] },    { "fieldType": "textarea", "name": "notes", "label": "Notes", "placeholder": "Anything we should know?" }  ],  "outputMode": "base64"}

Field types: text, textarea (multi-line, /Ff 4096), checkbox, radio, dropdown, listbox; placeholder shows hint text while a field is empty. Add encrypt to produce a password-protected form that keeps its AcroForm. Under a PDF/A claim pass embedFonts: true so the field font is embedded too (since v1.7.0 such a form validates under veraPDF); without it the call reports PDFA_UNEMBEDDED_FORM_FONT (strict: true then fails).

embed_image

{  "title": "Product Photo",  "imageBase64": "<base64-encoded JPEG bytes>",  "mimeType": "image/jpeg",  "caption": "Front view of Model X",  "width": 400,  "align": "center",  "alt": "Front view of the Model X chassis",  "outputMode": "base64"}

Note: the engine's PNG decoder accepts 8-bit, non-interlaced greyscale / RGB images only. Alpha-channel (colour type 4 / 6), palette (type 3), 16-bit and interlaced PNGs are rejected at the boundary with VALIDATION_ERROR and a remedy (flatten or re-export) — the same rule applies to image blocks and image watermarks. embed_image.imageBase64 keeps its 1.5.0 contract with no length bound; the 12 M-character cap applies to inline image blocks and watermark images only.

prepare_signature_placeholder

{  "title": "Service Agreement",  "signerName": "Alice Dupont",  "reason": "Approved",  "location": "Paris, FR",  "blocks": [    { "type": "paragraph", "text": "By signing below, I accept the terms and conditions." }  ],  "outputMode": "base64"}

Pass the returned PDF bytes to sign_pdf to complete the signing workflow.

inspect_pdf

Read-only structural and security inspection — useful for downstream verification, CI assertions, and AI agents that need to reason about a PDF before acting on it.

{  "pdfBase64": "<base64 PDF>",  "pages": true,  "check": ["pdfa", "signed", "attachments"]}

Returns:

{  "version": "1.7",  "pageCount": 3,  "encryption": "none",          // 'none' | 'aes-128' | 'aes-256' | 'rc4' | 'unknown'  "pdfA": "3B",                  // null when no PDF/A claim is present  "signatureCount": 1,  "hasSignaturePlaceholder": false,  "attachments": [{ "filename": "factur-x.xml", "mimeType": "application/xml", "sizeBytes": 1234, "relationship": "Source" }],  "info": { "Producer": "pdfnative", "Title": "Invoice INV-2025-001" },  "perPage": [{ "index": 0, "width": 595, "height": 842 }],  "checks": { "pdfa": true, "signed": true, "attachments": true },  "checksPassed": true}

check[] accepts any of 'pdfa', 'signed', 'encrypted', 'placeholder', 'attachments', 'dss', 'docTimestamp', 'trapped', 'annotations' (the last four since v1.6.0) and 'pdfx' (since v1.7.0: the XMP claims PDF/X — the claim, not its validity; that is validate_pdf standard: 'pdf-x-4'). pdfX appears in the result only when the XMP claims PDF/X (kept by verbosity: 'summary'). checksPassed is the AND of all requested checks. signatures: true adds a per-field inventory (subFilter, isDocTimestamp, isPlaceholder, byteRange, vriKey); annotations: true adds annotations[] (every /Annots entry: 0-based page, subtype, rect, and when present contents truncated to 200 chars, title, color, quadPoints, link url) plus annotationCount; dss, docTimestampCount and trapped appear only when present; with pages: true each perPage entry also carries trimBox / bleedBox / artBox / cropBox / userUnit when set.

inspect_layout

Read-only pagination dry run — the same blocks as generate_basic_pdf plus every input that moves a block (title, footerText, pdfA, normalize, embedFonts, pageSize, margins, headerTemplate, footerTemplate, and since v1.7.0 typography). No PDF is produced; pass exactly what you will give generate_basic_pdf and totalPages matches.

{ "title": "Memo", "blocks": [{ "type": "paragraph", "text": "Short note." }], "pageSize": "Letter", "verbosity": "summary", "fields": ["totalPages"] }

The full result carries pageWidth, pageHeight, margins, totalPages and pages[].blocks[] (type, page, x, top, width, height in points, rounded to two decimals). Since v1.7.0 the dry run and the build share one pagination planner, so every block kind — toc included — is measured exactly as it is laid out (in 1.6.0 a toc block was measured as 0 pt).

validate_pdf

Read-only structural conformance check. standard picks the rule set: 'pdf-ua-1' (default — PDF/UA, ISO 14289-1, for a Tagged PDF) or, since v1.7.0, 'pdf-x-4' (PDF/X-4, ISO 15930-7). Generate an accessible document with any tool using pdfA (e.g. pdfA: 'pdfa2u'), then validate the result:

{ "pdfBase64": "<tagged-pdf-base64>" }

Returns:

{  "standard": "pdf-ua-1",  "valid": true,  "errors": [],          // blocking structural violations (empty when valid)  "warnings": [],        // non-blocking best-practice recommendations  "summary": "PDF/UA structural prerequisites hold."}

It verifies catalog /MarkInfo /Marked true, /StructTreeRoot (+ /ParentTree), /Metadata (XMP), /Lang, and per-page MCID uniqueness. This is a fast developer-time gate — not a substitute for a full reference validator (veraPDF), which additionally checks fonts, colour, and rendering.

PDF/X-4 (v1.7.0). { "pdfBase64": "<pdf>", "standard": "pdf-x-4" } checks the structural prerequisites of ISO 15930-7: PDF 1.6 header, no encryption, trailer /ID, the PDF/X-4 XMP identification, a /GTS_PDFX output intent with an embedded prtr ICC profile, a TrimBox or ArtBox per page nested in the BleedBox and MediaBox, every font embedded, no annotation on the printed area, no JavaScript, no embedded file, device colour consistent with the output intent. The result has the same shape plus caveats[], which states what a valid: true verdict does not establish: this is not a certified preflight, and veraPDF does not cover PDF/X — confirm a press job with callas pdfToolbox or Acrobat Preflight. The default (pdf-ua-1) response is unchanged and carries no caveats.

annotate_pdf

Overlay markup annotations on an existing PDF via incremental update. This is a visual review layer, not a redaction — the underlying content is untouched.

{  "pdfBase64": "<base64 PDF>",  "annotations": [    { "type": "highlight", "page": 0, "rect": [72, 700, 520, 715], "color": [1, 1, 0], "contents": "Check this figure" },    { "type": "text", "page": 0, "rect": [540, 700, 560, 720], "contents": "Reviewer note" }  ]}

Types: text, highlight, underline, strikeout, squiggly, square, circle, line, freetext. Page indices are 0-based. color / interiorColor take a hex or operand string (including a CMYK operand string), a 0–1 RGB triple ([1, 1, 0]) or, since v1.7.0, a CMYK percent tuple ([0, 0, 100, 0]); v1.7.0 also fixes the 0–1 triple, which used to render almost black. Encrypted sources are rejected (ENCRYPTED_SOURCE) — run decrypt_pdf first (drops signatures / AcroForm), annotate, then encrypt_pdf again.

draft_governance_issue

Draft a governance-compliant GitHub issue locally for a human to review and submit. The server never contacts GitHub (its only possible egress is the operator-configured TSA / OCSP / CRL endpoints — see Network & egress); it returns the draft Markdown plus a machine-readable compliance report.

{  "title": "add_table drops the caption on the second page",  "issueType": "bug",  "summary": "The table caption is only rendered on page 1 when repeatHeader is true.",  "reproduction": { "command": "add_table with caption + repeatHeader over 2 pages (examples/bordered-table.json, then inspect_pdf)", "result": "Page 2 has no caption row." },  "expectedBehavior": "The caption repeats with the header on every page.",  "duplicateSearchPerformed": true}

A draft that proposes a runtime dependency, omits a reproduction, or sets duplicateSearchPerformed: false is rejected with GOVERNANCE_VIOLATION. See docs/guides/AI_GOVERNANCE.md for the full human-in-the-loop contract.

verify_pdf, add_attachment, extract_text

See the dedicated sections in docs/AI_GUIDE.md and the reference in docs/KNOWLEDGE_BASE.md. Ready-to-run examples live under examples/.

🔐 Security model

pdfnative-mcp runs inside the host process and exposes a stdio MCP server (or a loopback-only HTTP endpoint). It does not perform any I/O outside the configured sandbox.

• File writes are gated by PDFNATIVE_MCP_OUTPUT_DIR. When unset, the file output mode is rejected with a SecurityError.
• Path resolution rejects absolute paths, traversal sequences (..), NUL bytes, and any extension other than .pdf.
• Output size is capped at 50 MB per call.
• Inputs are validated against strict JSON Schemas + Zod runtime checks at the boundary of every tool — unknown or misspelt keys (top-level or nested) are rejected with VALIDATION_ERROR, and base64 / DER payloads are sanity-checked (data: prefix tolerated, PEM or double-encoded input rejected with the remedy) before any parser runs.
• HTTP transport (PDFNATIVE_MCP_PORT) binds loopback only; it has no authentication unless PDFNATIVE_MCP_HTTP_TOKEN is set (then 401 without a valid bearer token).
• Operator fonts (PDFNATIVE_MCP_FONT_DIR) are parsed by the engine before they are registered, bounded in number and size, and named by slug only — a tool argument never carries a path. The output base URL (PDFNATIVE_MCP_OUTPUT_BASE_URL) is pure string formatting: the server never requests it. Password calls are never cached.
• Fuzzed boundary — five ClusterFuzzLite targets (fuzz/: tools/call arguments, base64, images, the output sandbox, the HTTP guards) run on every pull request and weekly; the same targets run against src/ at every gate (tests/fuzzing/).

Network & egress

The server makes no outbound network call by default. The only egress it can ever perform goes to the RFC 3161 / OCSP / CRL endpoints the operator configured in the environment for PAdES long-term validation (PDFNATIVE_MCP_TSA_URL, PDFNATIVE_MCP_REVOCATION, PDFNATIVE_MCP_NETWORK_ALLOWED_HOSTS) — never to a URL supplied by a tool argument, never to GitHub, never for telemetry. Without that configuration sign_pdf timestamp: true, timestamp_pdf and add_ltv mode: 'online' fail fast with TSA_NOT_CONFIGURED / REVOCATION_NOT_CONFIGURED before touching the document; add_ltv mode: 'offline' embeds caller-supplied material with zero network access.

OCSP / CRL URLs come from the AIA / CRL-distribution-point extensions of untrusted certificates inside the PDF, so every fetch passes an SSRF guard:

• host must match the operator allow-list (host, host:port or *.suffix; bare wildcards are rejected). Entries are hostnames, not URLs: a host:port entry only matches URLs carrying an explicit port (the URL parser drops default :80 / :443 — list the bare host for those); wildcard entries cannot carry a port; IDN hostnames must be listed in punycode (xn--…); IPv6 literals in brackets ([2001:db8::1]);
• http: / https: only, no embedded credentials, redirects are never followed;
• loopback, link-local, private, unique-local, CGNAT, unspecified and multicast address literals (including decimal / octal / hex spellings and IPv4-mapped IPv6) are rejected unless that literal is allow-listed verbatim. The guard checks literals only — a listed hostname that resolves to an internal address (DNS rebinding) is not detected, since there is no resolver without adding a dependency; allow-list only hosts you control;
• per-request timeout (PDFNATIVE_MCP_NETWORK_TIMEOUT_MS) and response caps (256 KiB TSA, 1 MiB OCSP, 16 MiB CRL) enforced while streaming, so an oversized response is cut off rather than buffered;
• OCSP responses and CRLs returned by responders are parse-validated before add_ltv embeds them;
• the TSA URL is operator-trusted (scheme + credential checks only); the PDFNATIVE_MCP_TSA_AUTH secret is never logged or echoed in error messages.

Providers are built per call and passed through pdfnative's per-call options — the process-wide provider setters are never used, so concurrent requests share nothing. The server/discover instructions report the current egress policy (endpoint kinds only, never secrets).

See SECURITY.md for the responsible disclosure process and docs/guides/LTV.md for the operator setup.

🧪 Local development

git clone https://github.com/Nizoka/pdfnative-mcp.gitcd pdfnative-mcpnpm ci                    # .npmrc sets ignore-scripts=true: nothing builds on installnpm run gate:fast         # before every commit: typecheck:all, lint, test, server-json, verify:docsnpm run gate              # the CI profile: build, dist checks, stdio smoke test, tool shape, pack manifest, samples, coverage, docs, corpus, validate:pdfxnpx tsx scripts/gate.ts --publish --require-all   # release branches: everything incl. validate:pdfa (veraPDF); a skipped step fails

npm run gate (scripts/gate.ts) is the single definition of green — 1804 tests, the coverage thresholds of vitest.config.ts, and the built server driven over stdio, where stdout must carry JSON-RPC frames only. It prints one line per step and writes the logs to test-output/.gate/<step>.log; --only <step> runs one step and --json gives machine output (call the script directly to pass flags: npx tsx scripts/gate.ts --fast). The individual steps are ordinary npm scripts:

npm run build && npm run test:generate   # drive the built server under TZ=UTC, operator variables scrubbed -> test-output/samples/npm run verify:samples    # hold the 112 samples to tests/_fixtures/samples.sha256.json (109 by bytes, 3 by a semantic projection)npm run corpus:pdfa       # write the 45-file conformance corpus (36 claim PDF/A, 6 claim PDF/X-4, 1 claims both — the PDF/X-4 + PDF/A-2 dual claim —, 2 page-tree outputs claim nothing)npm run validate:pdfx     # in-process structural PDF/X-4 check of the corpus; never skipsnpm run validate:pdfa     # veraPDF over the PDF/A files (VERAPDF_HOME, JAVACMD); exit 0 ok / 1 conformance / 2 infrastructurenpm run verify:docs       # every count, version, tool, error code, operator variable, link and anchor in the docs vs docs/assets/ecosystem.json and src/npx tsx scripts/tool-shape.ts --write   # only after a deliberate tools/list schema change (npm run verify:tool-shape checks the fixture)npx vitest run tests/fuzzing/targets.test.ts   # the five ClusterFuzzLite targets against src/ on their seeded corpus (also part of npm test)

An intended output change is rebaselined with npx tsx scripts/verify-samples.ts --update and declared in the release note — never to silence a surprise. With veraPDF 1.30.2 the corpus gives 27 PASS and 6 expected failures (negative canaries that must stay rejected). Every script, its flags and its exit codes are listed in scripts/README.md.

Smoke-test the server over stdio:

node dist/cli.js# In another terminal, send a JSON-RPC initialize request via stdin (e.g. with mcp-inspector).

Contributors: start at AGENTS.md (the repository rules shared by every coding agent and contributor) and see docs/guides/LOCAL_TESTING.md for the full local-verification workflow — the quality gate, examples-as-tests, validating that generated PDFs are structurally correct (assertValidPdf, inspect_pdf, validate_pdf, verify_pdf), opening output in a viewer, external PDF/A checking with veraPDF, and the MCP Inspector.

📣 Release process

pdfnative-mcp follows the same release formalism as pdfnative:

• One release note file per tag in release-notes/vX.Y.Z.md
• CHANGELOG.md mirrors each release bullet list
• GitHub Release body is copied from release-notes/vX.Y.Z.md
• npx tsx scripts/release-prepare.ts --version X.Y.Z applies the mechanical part of a version bump (it never commits, tags or publishes); the version moves in lock-step across package.json, src/version.ts, server.json and docs/assets/ecosystem.json
• A release branch must pass npx tsx scripts/gate.ts --publish --require-all — every step, veraPDF included, with no skip
• npm publication is handled by GitHub Actions Trusted Publishing (OIDC), without NPM_TOKEN, from a protected environment, through the five-job pipeline of pdfnative 1.9 (publish.yml: guard refuses anything but a v* tag equal to the package version before any approval → build runs the publish gate and packs once, digests recorded → publish installs nothing, fetches the npm client by SHA-512, re-verifies the tarball and publishes with --provenance → attest fetches the bytes the registry serves, checks them against the build digests, runs npm audit signatures, attests them with three SBOMs (CycloneDX + SPDX runtime, CycloneDX toolchain) and attaches everything plus the Sigstore bundle to the GitHub release → registry publishes server.json to the MCP registry with the workflow's OIDC identity through a SHA-256- and cosign-verified mcp-publisher)
• Every Linux and Windows job starts with step-security/harden-runner — egress blocked with an allow-list on the Linux jobs, audited with a dated reason elsewhere (Windows supports audit only; the action does not support macOS, the one documented exemption) —, checks out with persist-credentials: false, installs with npm ci --ignore-scripts, pins every action to a commit SHA, scopes every write permission to its job and passes event values through env:; workflow-lint (zizmor + checksummed actionlint) is a required check beside the gate on three operating systems and the sample baseline; CodeQL (actions + javascript-typescript, security-extended), Scorecard, Dependency Review, a weekly npm audit and ClusterFuzzLite complete the picture
• Human-in-the-loop: coding agents prepare and verify; the maintainer pushes, opens the pull request, tags and publishes (.github/AGENT_RULES.md)

See release-notes/TEMPLATE.md for the canonical structure and publication checklist, and CONTRIBUTING.md for the release procedure.

📚 Project structure

src/├── cli.ts                      # entrypoint: stdio (default) or Streamable HTTP (PDFNATIVE_MCP_PORT)├── http.ts                     # Node http <-> Web Request/Response bridge + Host/Origin loopback guard├── auth.ts                     # opt-in HTTP bearer token (PDFNATIVE_MCP_HTTP_TOKEN)├── base64.ts                   # base64 / DER boundary decoding with agent-facing diagnostics├── index.ts                    # public library exports├── server.ts                   # Server factory, tool registry, cache hints, SERVER_INSTRUCTIONS├── network.ts                  # operator-configured TSA / OCSP / CRL egress + SSRF guard├── print.ts                    # print-production schema (boxes, bleed, marks + colour bars, userUnit, RGB / CMYK / Gray outputIntent, metadata, creationDate)├── pdfx.ts                     # pdfx: 'pdfx4' conformance target + the static conflicts refused before the build├── color.ts                    # shared colour fragment: CMYK operand string / percent tuple beside each historical form, toEngineColor()├── typography.ts               # the typography fragment (12 opt-in keys) + TypographyOptions mapper├── reproducible.ts             # operator-pinned creation instant (PDFNATIVE_MCP_CREATION_DATE, SOURCE_DATE_EPOCH)├── diagnostics.ts              # engine diagnostics sink (PDFA_* / PDFX_* / TYPOGRAPHY_*), strict escalation by code, includeDiagnostics, embedFonts├── chart.ts                    # charts v2 schema + ChartBlock mapper├── blocks.ts                   # the 7 extended document blocks (table, image, link, toc, barcode, svg, formField)├── layout.ts                   # pageSize / margins / header & footer templates / compress / debug / encrypt / typography (PdfLayoutOptions)├── table.ts, barcode.ts, form.ts, image.ts   # bodies shared by a dedicated tool and its inline block├── watermark.ts                # text and/or image watermark + position, PDF/A-1b transparency guard├── encryption.ts               # password + encrypt schema (Standard Security Handler), decrypt error mapping├── inflate-cap.ts              # PDFNATIVE_MCP_MAX_INFLATE_BYTES (engine decompression cap) + PDF_PARSE_FAILED mapping├── output.ts                   # sandboxed file writer / base64 emitter (single + multi)├── text.ts                     # newline sanitizer (Safe PDF/A)├── doc-features.ts             # nested lists, outline, page labels, viewer prefs (+ print-dialog defaults)├── pagetree.ts                 # page-tree error mapping (merge/split/extract)├── crypto-provider.ts          # node:crypto signing provider for DER keys (SHA-256/384/512); verification stays pure JS├── projection.ts               # verbosity / fields projection for the seven read tools├── errors.ts                   # ToolError, SecurityError, GovernanceError└── tools/    ├── generate-basic-pdf.ts    ├── inspect-layout.ts    ├── add-barcode.ts    ├── sign-pdf.ts    ├── add-ltv.ts    ├── timestamp-pdf.ts    ├── update-metadata.ts    ├── add-international-text.ts    ├── add-table.ts    ├── add-form.ts    ├── read-form-fields.ts    ├── fill-form.ts    ├── add-chart.ts    ├── embed-image.ts    ├── inspect-pdf.ts    ├── verify-pdf.ts    ├── validate-pdf.ts    ├── add-attachment.ts    ├── extract-attachments.ts    ├── extract-text.ts    ├── merge-pdfs.ts    ├── split-pdf.ts    ├── extract-pages.ts    ├── annotate-pdf.ts    ├── encrypt-pdf.ts    ├── decrypt-pdf.ts    ├── draft-governance-issue.ts    └── prepare-signature-placeholder.tsscripts/                        # TypeScript run by tsx — the full table is in scripts/README.md├── gate.ts                     # THE quality gate (npm run gate / gate:fast; --publish --require-all on release branches)├── generate-samples.ts         # npm run test:generate — the built server under TZ=UTC -> test-output/samples/├── verify-samples.ts           # npm run verify:samples — the byte baseline (tests/_fixtures/samples.sha256.json)├── generate-pdfa-corpus.ts     # npm run corpus:pdfa — the 41-file PDF/A + PDF/X-4 conformance corpus├── validate-pdfa.ts            # npm run validate:pdfa — veraPDF (PASS/FAIL/XFAIL/XPASS; exit 0 / 1 / 2)├── validate-pdfx.ts            # npm run validate:pdfx — in-process structural PDF/X-4 check, never skips├── tool-shape.ts               # structural tools/list fingerprint (--write refreshes tests/_fixtures/tool-shape.json)├── verify-docs.ts              # npm run verify:docs — the docs held to docs/assets/ecosystem.json and the source tree├── release-prepare.ts          # mechanical version bump (never commits, tags or publishes)├── build-claude-rules.ts       # npm run agents:rules — .github/instructions/ -> .claude/rules/└── verify-issue.mjs            # governance draft checker (npm run verify:issue)docs/├── AGENT_CONTRACT.md           # the consumer contract for agents that USE the server (catalogue, decision tree, recipes, error codes)├── AI_GUIDE.md, KNOWLEDGE_BASE.md, API_STABILITY.md├── guides/                     # PDFA, PRINT, TYPOGRAPHY, REPRODUCIBLE, CHARTS, FORMS, ENCRYPTION, LTV, AI_GOVERNANCE, LOCAL_TESTING└── assets/ecosystem.json       # the single source of every count and version quoted in the docsexamples/                       # 43 executable tools/call sequences (npm run examples:check)AGENTS.md, CLAUDE.md            # repository rules for coding agents; .github/instructions/ holds the per-area rules.claude/                        # shared agent settings, the fail-closed guard hook, generated rules, the release-audit skill.github/workflows/              # ci (Node 22 / 24 on Linux, plus Windows and macOS, all running the gate, all required), publish, sample-regression, verapdf (blocking),                                #   docs, codeql, scorecard, dependency-review, audit.github/rulesets/               # branch and tag rulesets to importtests/                          # vitest suites (one per tool / module), _fixtures/ (tool shape, sample baseline, engine-surface matrix,                                #   the frozen 1.5.0 catalogue), tools/ (repository tooling)

🗺 Roadmap

v1.8.0 is shipped (spot colours, right-to-left documents, 32 Unicode scripts, JPEG 2000, the PDF/X-4 + PDF/A-2 dual claim, link annotations, operator fonts, the output base URL, the pdfnative 1.9 release pipeline and fuzzing), on top of v1.7.0 (fine typography, CMYK colours, PDF/X-4, reproducible output on every host) and v1.6.0 (full engine coverage — 13 block kinds, layout options, inspect_layout — PAdES LTV ladder, print production, charts v2, update_metadata, MCP 2026-07-28). The full plan — released milestones, in-progress work, and long-term direction — lives in ROADMAP.md.

Still deferred:

• redact_pdf — pdfnative has no content-removal API; an overlay-only "redaction" would create false security.
• HTTP page streaming — MCP 2026-07-28 still has no partial structuredContent, so large results stay single-shot.
• A Thai above vowel + tone mark pair extracts in geometric order on untagged output (every other right-to-left or reordered run round-trips through /ActualText since pdfnative 1.9; tagged output always does).
• Non-Latin-1 form values: the engine writes only the low byte of each UTF-16 code unit of a fill_form value under nonWinAnsi: 'needAppearances', so Ω or 漢 do not round-trip through read_form_fields — pinned upstream.
• Fuzz corpora survive only as long as the GitHub Actions cache; a dedicated storage repository is the next step. The OpenSSF Best Practices badge needs the maintainer's registration (docs/OPENSSF_BEST_PRACTICES.md is the prepared self-assessment).

Have a feature idea? Open an issue or PR.

🧭 Client compatibility

Every tool schema is JSON Schema 2020-12 without $ref / $defs, so hosts that forward inputSchema to a function-calling API get self-contained schemas. Since v1.8.0 every array bound is 1000 or below, or exactly 5000 (the blocks, rows and pages arrays): llama.cpp's llama-server compiles the tool schemas of a request into one GBNF grammar and refused the former 2000-item bound of prepare_signature_placeholder (#65); tests/client-compat.test.ts holds the rule. The 28 schemas weigh about 83 k tokens with a Qwen tokenizer — a client that forwards every tool on every request can disable the ones it does not need (sign_pdf injects its own placeholder, so prepare_signature_placeholder is optional; inspect_layout is a dry run of generate_basic_pdf).

🌱 Ecosystem

• pdfnative — the zero-dependency engine every feature here comes from.
• pdfnative-cli — the terminal wrapper of the same engine, for pipelines and shell agents.
• pdfnative-react — React renderer (JSX → pdfnative blocks).
• zipnative and pkinative — the sibling zero-dependency engines (archives, PKI); the native family guide explains how the four fit together.

⭐ Star the project

If pdfnative-mcp is useful to you, please ⭐ this repository — and consider also starring the underlying engine Nizoka/pdfnative. Stars help others discover the project and motivate continued development.

🤝 Contributing

Contributions are very welcome. Please read CONTRIBUTING.md, check the open issues, and follow the code of conduct.

📄 License

MIT © 2026 Nizoka. Third-party material: THIRD-PARTY-NOTICES.md.

pdfnative-mcp is built on top of pdfnative and the Model Context Protocol TypeScript SDK.