fix(pdf-server): npx DOMMatrix crash + broken MCPB bundle#584
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…i-rs/canvas pdfjs-dist/legacy/build/pdf.mjs does `new DOMMatrix()` at module scope. Its own polyfill loads @napi-rs/canvas (an optionalDependency), but npx frequently misses the platform-native binary (npm/cli#4828), so the server crashed on `npx @modelcontextprotocol/server-pdf --stdio`: ReferenceError: DOMMatrix is not defined at pdfjs-dist/legacy/build/pdf.mjs:17078 The server only uses pdfjs for text/metadata/form-field extraction — never canvas rendering — so no-op stubs suffice and avoid shipping ~130MB of native binaries. The polyfill is a separate ESM module kept --external in the bun bundle so it executes before pdfjs's hoisted static import; inlined body code would run too late. Broken since 1.3.0 (#506). Thanks to Bryan Thompson for the analysis and fix shape from the npm-to-mcpb pipeline.
@modelcontextprotocol/ext-apps
@modelcontextprotocol/server-basic-preact
@modelcontextprotocol/server-basic-react
@modelcontextprotocol/server-basic-solid
@modelcontextprotocol/server-basic-svelte
@modelcontextprotocol/server-basic-vanillajs
@modelcontextprotocol/server-basic-vue
@modelcontextprotocol/server-budget-allocator
@modelcontextprotocol/server-cohort-heatmap
@modelcontextprotocol/server-customer-segmentation
@modelcontextprotocol/server-debug
@modelcontextprotocol/server-map
@modelcontextprotocol/server-pdf
@modelcontextprotocol/server-scenario-modeler
@modelcontextprotocol/server-shadertoy
@modelcontextprotocol/server-sheet-music
@modelcontextprotocol/server-system-monitor
@modelcontextprotocol/server-threejs
@modelcontextprotocol/server-transcript
@modelcontextprotocol/server-video-resource
@modelcontextprotocol/server-wiki-explorer
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… spaces `mcpb pack` zips whatever is on disk; in this monorepo all runtime deps are hoisted to root node_modules, so the published .mcpb shipped without pdfjs-dist/ajv/express/etc. and crashed on import in Claude Desktop. build-mcpb.mjs stages dist/ + manifest into a clean temp dir, runs a non-workspace `npm install --omit=dev --omit=optional` (the new DOMMatrix polyfill makes @napi-rs/canvas's ~130MB of native binaries unnecessary), syncs manifest.version to package.json, then packs. Result: 12.3MB / 38.8MB unpacked, full MCP handshake + tools/list pass. Also rename display_name "PDF (By Anthropic)" → "pdf-viewer" — spaces in display_name break MCP App UI rendering for MCPBs in Claude Desktop. CI now smoke-tests the extracted bundle starts (`dist/index.js --stdio` prints "Ready") so a deps-less bundle can't ship again.
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Changes since 1.3.2: - feat: add addEventListener/removeEventListener with DOM-model on* semantics (#573) - feat(pdf-server): add save_as interact action (#580) - feat(pdf-server): fit-to-page on fullscreen + pinch-to-zoom (#583) - fix(pdf-server): npx DOMMatrix crash + broken MCPB bundle (#584) - fix(pdf-server): viewer liveness, 1:1 batch results, fullscreen jitter (#579) - fix(pdf-server): render page before O(numPages) annotation scans (#581) - fix(pdf-server): radio + dropdown in fill_form/save (#577) - fix(deps): bump path-to-regexp 8.3.0 → 8.4.1 to patch ReDoS CVEs (#576)
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Changes since 1.3.2: - feat: add addEventListener/removeEventListener with DOM-model on* semantics (#573) - feat(pdf-server): add save_as interact action (#580) - feat(pdf-server): fit-to-page on fullscreen + pinch-to-zoom (#583) - fix(pdf-server): npx DOMMatrix crash + broken MCPB bundle (#584) - fix(pdf-server): viewer liveness, 1:1 batch results, fullscreen jitter (#579) - fix(pdf-server): render page before O(numPages) annotation scans (#581) - fix(pdf-server): radio + dropdown in fill_form/save (#577) - fix(deps): bump path-to-regexp 8.3.0 → 8.4.1 to patch ReDoS CVEs (#576) - chore(deps): npm audit fix — sdk 1.29.0, systeminformation 5.31.5, +13 transitives (#585, #586)
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Changes since 1.3.2: SDK - feat: add addEventListener/removeEventListener with DOM-model on* semantics (#573) pdf-server - feat: add save_as interact action (#580) - feat: fit-to-page on fullscreen + pinch-to-zoom (#583) - fix: npx DOMMatrix crash + broken MCPB bundle (#584) - fix: viewer liveness, 1:1 batch results, fullscreen jitter (#579) - fix: render page before O(numPages) annotation scans (#581) - fix: radio + dropdown in fill_form/save (#577) Dependencies - chore: npm audit fix — sdk 1.29.0, systeminformation 5.31.5, +13 transitives (#585, #586) - fix: bump path-to-regexp 8.3.0 → 8.4.1 to patch ReDoS CVEs (#576)
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Changes since 1.3.2: SDK - feat: add addEventListener/removeEventListener with DOM-model on* semantics (#573) pdf-server - feat: add save_as interact action (#580) - feat: fit-to-page on fullscreen + pinch-to-zoom (#583) - fix: npx DOMMatrix crash + broken MCPB bundle (#584) - fix: viewer liveness, 1:1 batch results, fullscreen jitter (#579) - fix: render page before O(numPages) annotation scans (#581) - fix: radio + dropdown in fill_form/save (#577) Dependencies - chore: npm audit fix — sdk 1.29.0, systeminformation 5.31.5, +13 transitives (#585, #586) - fix: bump path-to-regexp 8.3.0 → 8.4.1 to patch ReDoS CVEs (#576)
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* chore: bump ext-apps to 1.4.0 Changes since 1.3.2: SDK - feat: add addEventListener/removeEventListener with DOM-model on* semantics (#573) pdf-server - feat: add save_as interact action (#580) - feat: fit-to-page on fullscreen + pinch-to-zoom (#583) - fix: npx DOMMatrix crash + broken MCPB bundle (#584) - fix: viewer liveness, 1:1 batch results, fullscreen jitter (#579) - fix: render page before O(numPages) annotation scans (#581) - fix: radio + dropdown in fill_form/save (#577) Dependencies - chore: npm audit fix — sdk 1.29.0, systeminformation 5.31.5, +13 transitives (#585, #586) - fix: bump path-to-regexp 8.3.0 → 8.4.1 to patch ReDoS CVEs (#576) * chore: update e2e snapshots [skip ci] --------- Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
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Two related distribution fixes (both broken since 1.3.0/#506):
1.
npxcrashes withDOMMatrix is not definedpdfjs-dist/legacy/build/pdf.mjsdoesnew DOMMatrix()at module scope. Its own polyfill loads@napi-rs/canvas(an optionalDependency), butnpxfrequently misses the platform-native binary (npm/cli#4828), sonpx @modelcontextprotocol/server-pdf --stdiocrashed.The server only uses pdfjs for text/metadata/form-field extraction — never canvas rendering — so no-op stubs in
pdfjs-polyfill.tssuffice. Kept--externalin the bun bundle so it executes before pdfjs's hoisted static import.2. MCPB bundle ships without runtime deps
mcpb packzips whatever is on disk; in this monorepo all deps are hoisted to rootnode_modules, so the published.mcpbshipped 15 files with nopdfjs-dist/ajv/expressand crashed on import in Claude Desktop.build-mcpb.mjsnow stagesdist/+ manifest into a clean temp dir, runs a non-workspacenpm install --omit=dev --omit=optional(~130MB of@napi-rs/canvasbinaries skipped — the polyfill makes them unnecessary), syncsmanifest.versiontopackage.json, then packs. CI smoke-tests the extracted bundle starts.Also:
display_name"PDF (By Anthropic)"→"pdf-viewer"(spaces break MCP App UI rendering for MCPBs in Claude Desktop).Thanks @bryan-anthropic for the analysis from the npm-to-mcpb pipeline.
Tested:
npm pack+--omit=optionalinstall starts cleanly;bun test164/164;.mcpbunzip +initialize/tools/listhandshake returns 8 tools.