The Windows WSL job is the critical path of every CI run (589 to 752 s).
Its checkout sits on the Windows drive, which WSL reaches over 9P, and
writing node_modules there is what makes npm ci take about three minutes
where the Linux job takes 23 s. The step now copies the tree onto the
distro's ext4 filesystem before installing and building, as Microsoft's
WSL guidance recommends for I/O-heavy work.
The e2e job downloaded the full Chromium build (about 165 MB) on every
run, but a headless run with no channel launches chromium-headless-shell
and never opens it. `--only-shell` skips that download.
Every tsconfig now lists the @types packages it uses (node, bun,
vite/client, dom-speech-recognition) instead of relying on TypeScript
auto-including everything under node_modules/@types. On TypeScript 5.9
this is a no-op: identical diagnostics across all 48 projects and
byte-identical emitted .d.ts files. It is a prerequisite for TypeScript 7,
which drops the auto-inclusion; with these lists the Go compiler passes
all 48 projects, so that upgrade becomes a version bump once TypeDoc
supports it.
Two cache-based approaches were evaluated and rejected: an npm cache for
the WSL job (npm ci is slow there because of 9P, not downloads, and a
prefix-restored cache grows without bound) and a Playwright browser cache
(Playwright's docs advise against it; the download is under 10 s).
* lazy PDF loading w/ PDFDataRangeTransport
* lint
* feat: lazy PDF loading via range transport + eager background preloading
Replace full-file download with PDFDataRangeTransport so PDF.js fetches
byte ranges on demand. First page renders immediately; remaining pages
load in background for search.
**Range transport (server + client)**
- server.ts: add read_pdf_bytes tool returning base64 chunks with offset
- mcp-app.ts: AppRangeTransport feeds PDF.js via fetchRange/fetchChunk
with parallel sub-requests for large ranges, Promise-based dedup of
concurrent requests, and a persistent range cache
**Background preloader**
- Sequential page 1→N text extraction, pauses during interactive
navigation (preloadPaused flag set in goToPage, cleared in renderPage)
- Debounced live search refresh (500ms) as pages load
- Search UI shows '(loading…)' suffix until all pages processed
**Loading indicators**
- SVG pie in toolbar: fills as pages load, fades on completion,
turns red on errors with tooltip listing failed pages
- Debounced page-loading overlay (150ms) for uncached page navigation
**Cleanup**
- Remove old full-file chunked download and progress bar
- Remove extractAllPageText (replaced by preloader)
- Remove verbose debug logs (Coverage, RangeReq, cache hit)
* feat(pdf-server): Interactive PDF viewer example
PDF viewer with PDF.js featuring:
- Chunked binary loading with progress bar
- Text extraction for AI context
- arXiv paper support (fetch by ID)
- Page navigation with keyboard shortcuts
- Zoom controls (including Ctrl+0 reset)
- Fullscreen mode support
- Horizontal swipe for page changes (disabled when zoomed)
- Page persistence in localStorage
- Text selection via PDF.js TextLayer
- Clickable title link to source URL
- Rounded corners and subtle border styling
* chore: Add pdf-server to screenshot generation list
* refactor(pdf-server): Simplify and generalize PDF loading
- Accept any HTTP(s) URLs instead of ArXiv-only
- Use HTTP Range requests for chunked binary loading
- Remove ArXiv-specific code (arxiv.ts, metadata fetching)
- Remove CLAUDE.md index generation
- Flatten hierarchical folder structure to simple entries list
- Remove dead code: getPdfSummary, httpFileSizes
- Simplify base64 encoding using Buffer
- Simplify chunk extraction using slice()
- Consolidate DEFAULT_PDF_URL constant
The server now works with any PDF URL, not just arXiv papers.
HTTP Range requests stream chunks on-demand when supported.
* feat(pdf-server): Include title and selection in model context
- Add pdfTitle to updateModelContext structuredContent
- Include selection position (text, start, end) when text is selected
- Add debounced selectionchange listener to update context on selection
* fix(pdf-server): Restore default URL in view_pdf schema
The UI needs the default value in the schema to show it properly.
* refactor(pdf-server): Further simplifications
- Remove hard-coded test paths from main()
- Remove unused resources: pdfs://metadata/{pdfId}, pdfs://content/{pdfId}
- Remove unused metadata fields: subject, creator, producer, creationDate, modDate
- Remove unused entry fields: relativePath, estimatedTextSize
- Remove filterEntriesByFolder and folder filter from list_pdfs
- Remove redundant output schema validation (trust typed returns)
- Simplify scanDirectory and createLocalEntry signatures
Total: 1836 → 1666 lines (-170 lines, -9%)
* refactor(pdf-server): Major simplification for didactic focus
Simplified the example to focus on key MCP Apps SDK patterns:
- Chunked data through size-limited tool calls
- Model context updates (page text + selection)
- Display modes (fullscreen vs inline)
- External links (openLink)
Changes:
- Remove local file support (HTTP URLs only)
- Restrict dynamic URLs to arxiv.org for security
- Simplify types: url instead of sourcePath/sourceType
- Simplify indexer: 168 → 44 lines
- Simplify loader: 318 → 171 lines
- Simplify server: 337 → 233 lines
- Fix selection text normalization
- Rewrite README with didactic focus
Total: 1836 → 1236 lines (-33%)
* feat(pdf-server): Add file:// URL support for local files
- Local paths are converted to file:// URLs on startup
- file:// URLs must be in the initial list (strict validation)
- Dynamic URLs still restricted to arxiv.org only
- Updated README with local file examples
* fix(pdf-server): Improve selection detection with logging
- Add logging to selectionchange handler to verify it fires
- Add fallback matching without spaces (TextLayer spans may lack spaces)
- Log selection detection success/failure for debugging
The issue: PDF.js TextLayer renders text as positioned spans without
space characters between them. When selecting across spans:
- pageText has spaces (items joined with ' ')
- sel.toString() may not have spaces
- indexOf fails to match
The fix tries exact match first, then falls back to spaceless matching.
* feat(pdf-server): Format model context as markdown with front matter
Model context now looks like:
```markdown
---
url: https://arxiv.org/pdf/...
page: 5/144
---
Page text with <pdf-selection>selected text</pdf-selection> inline.
```
This is cleaner for the model to parse and includes the source URL.
* refactor(pdf-server): Extract smart truncation helpers
Added two well-designed helpers:
formatPageContent(text, maxLength, selection?)
- Centers truncation window around selection if present
- Adds <truncated-content/> markers at elision points
- Wraps selection in <pdf-selection> tags
- Allocates 60% context before, 40% after for readability
findSelectionInText(pageText, selectedText)
- Tries exact match first
- Falls back to spaceless match for TextLayer quirks
- Returns { start, end } or undefined
Example output with selection:
```
<truncated-content/>
...context before... <pdf-selection>selected text</pdf-selection> ...context after...
<truncated-content/>
```
* fix(pdf-server): Truncate inside selection tags when selection too long
When selection is too large for the budget:
<truncated-content/><pdf-selection><truncated-content/>start...end<truncated-content/></pdf-selection><truncated-content/>
This keeps the selection structure intact while showing beginning and end.
* refactor(pdf-server): Remove unused read_pdf_text, use Attention paper as default
- Remove read_pdf_text tool (viewer extracts text client-side with pdfjs)
- Remove PdfTextChunk and ReadPdfTextInput types
- Remove loadPdfTextChunk from pdf-loader
- Change default PDF to 'Attention Is All You Need' (1706.03762)
- Update README with modest language
* refactor(pdf-server): Simplify to use URL as ID, rename view_pdf to display_pdf
Major simplifications:
- Use URL directly as identifier (no hashing)
- Remove displayName - show elided URL with full URL as tooltip
- Rename view_pdf to display_pdf with better description
- Update all references from pdfId to url
- Simplify storage key and model context
The tool description now explains it displays an interactive viewer in the chat.
* feat(pdf-server): Normalize arxiv URLs to PDF format
arxiv.org/abs/... -> arxiv.org/pdf/...
Applied both at startup and when loading dynamic URLs.
* docs(pdf-server): Add prompt engineering to display_pdf description
* fix(pdf-server): Sharp rendering on retina displays
Account for devicePixelRatio when rendering canvas:
- Scale canvas dimensions by dpr
- Scale context by dpr
- Keep CSS size at logical pixels
* fix(pdf-server): Normalize arxiv URLs in read_pdf_bytes too
* add to e2e spec
* add to e2e spec
* add to e2e spec
* add to e2e spec
* regen
* chore: regenerate package-lock.json and fix hono vulnerability
* docs: add pdf-server screenshot to READMEs
* regen
* ci: add missing examples to pkg-pr-new publish
* ci: add pdf-server to npm publish examples
* Update README.md
* pdf-server: improve tool response text for better model context
* revert unrelated screenshot changes
* pdf-server: dynamically add arxiv URLs in read_pdf_bytes
Fixes 'PDF not found' error when server restarts between display_pdf
(which adds the entry) and read_pdf_bytes (which previously only looked
up existing entries). Now read_pdf_bytes mirrors display_pdf's logic
and dynamically adds arxiv URLs to the index.
Olivier Chafik