Users frequently call callServerTool("tool_name", args) instead of the
correct callServerTool({ name: "tool_name", arguments: args }), resulting
in a silent/confusing failure. Detect this and throw immediately with
a message that shows the correct call shape.
Also fixes the incorrect example in examples/pdf-server/README.md that
demonstrated this same wrong usage pattern.
Fixes#386https://claude.ai/code/session_01GqAyN4Ux7svWoU2HqsSLZF
Co-authored-by: Claude <noreply@anthropic.com>
* chore: add stable spec release 2026-01-26
- Use git mv to copy specification from draft to specification/2026-01-26/apps.mdx (preserves history)
- Update status from 'Draft' to 'Stable (2026-01-26)'
- Add specification version table to README
- Update Resources section with links to both stable and draft specs
* chore: bump version to 1.0.0
- Update main package version from 0.4.2 to 1.0.0
- Update all example package versions to 1.0.0
- Regenerate package-lock.json
* prettier
* chore: align protocol version with spec release 2026-01-26
- Add 'Protocol Version: 2026-01-26' to spec header
- Update LATEST_PROTOCOL_VERSION from '2025-11-21' to '2026-01-26'
- Update spec examples to use '2026-01-26' protocol version
- Add '2025-11-21' to SUPPORTED_PROTOCOL_VERSIONS for backwards compatibility
* chore: update spec references to stable 2026-01-26
- Update typedoc.config.mjs navigation link
- Update docs/overview.md spec links (10 occurrences)
- Update plugins/mcp-apps/skills/create-mcp-app/SKILL.md spec link
- Update src/spec.types.ts @see links
- Update AGENTS.md spec path
- Regenerate src/generated/schema.ts with updated links
* chore: simplify versioning - first stable release
- Remove backwards compatibility version (2025-11-21) - this is the first stable release
- Remove redundant 'Protocol Version' header - spec version IS the protocol version
* chore: add history reference comment to stable spec
* docs: add local development MCP client configuration to READMEs
Add instructions for configuring MCP clients to use locally-cloned
and modified servers. This allows developers to test local changes
with MCP clients like Claude Desktop or VS Code.
- Top-level README: Added 'Local Development' section after npx config
- All TypeScript examples: Added 'Local Development' subsection with
bash one-liner that builds and runs the server
- Python examples (qr-server, say-server): Added local path config
* docs: include all servers in local development config
* docs: use bash wrapper for Python server configs to enable tilde expansion
* fix(map-server): simplify location update message format
* fix(say-server): pass host to streamable_http_app for non-localhost deployments
* refactor(pdf-server): simplify to stateless range-query architecture
- Remove caching/indexing in favor of direct HTTP Range requests
- Use HEAD requests to get file size (no full download)
- Use Range requests to proxy byte chunks (no caching)
- Local files: fs.read with offset/length
- Remote files: HTTP Range header
- Zero memory footprint (no PDF caching)
- Truly stateless (no session management needed)
- Single server.ts (~350 lines) + main.ts CLI entry point
- Instant startup (no preloading)
- Security: whitelist local files, allowed origins
Removed files:
- src/pdf-indexer.ts
- src/pdf-loader.ts
- src/types.ts
* feat(pdf-server): add dark mode support
- Add CSS variables with light-dark() function for automatic theme switching
- Sync theme with host via applyDocumentTheme()
- Apply host CSS variables via applyHostStyleVariables()
* feat(pdf-server): add list_pdfs tool back
Lists local files and allowed remote origins.
Also moves CHUNK_SIZE to module level constant.
* feat(pdf-server): improve tool descriptions and increase context limit
- display_pdf: list all allowed domains in description
- Increase MAX_MODEL_CONTEXT_LENGTH to 15000
- Move CHUNK_SIZE to module level constant
* chore(say-server): remove deployment docs from repo
Keep server.py fix for non-localhost deployments.
Deployment docs kept locally but not in repo.
* refactor(pdf-server): simplify updateModelContext format
- Add widget ID for multi-widget disambiguation
- Use concise header: 'PDF viewer (id) | title | Current Page: X/Y'
- Add 'Page content:' prefix before text
- Keep selection markers (<pdf-selection>...</pdf-selection>)
* refactor: rename widgetUUID to viewUUID for consistency
Aligns with main's standardization on 'view' terminology (PR #325).
Also dynamically generate allowed domains in display_pdf description.
* viewUUID
* fix(map-server): fix syntax error in location update message
* fix(pdf-server): restore package.json, improve server docs
- Restore --external pdfjs-dist in build
- Rewrite server.ts header for newcomers (list tools, not implementation details)
- Minimize main.ts diff
* chore(pdf-server): remove unused addAllowedOrigin/addAllowedLocalFile
* docs(pdf-server): update README for new architecture
* docs(pdf-server): restore full README, add theming section, remove get_pdf_info
* rm
* fix(pdf-server): restore createMcpExpressApp and error handling
- Use createMcpExpressApp for DNS rebinding protection
- Restore error callback in app.listen()
* fix(say-server): pass host to streamable_http_app for non-localhost deployments
* chore(say-server): remove deployment docs from repo
* widgetId->tool id
* fix(map-server): add null check for center in location update
chore(pdf-server): dedupe and sort allowed origins
* fix(map-server): use transparent background for rounded corners
* prettier
Add stdio transport configuration snippets near the top of each example
README to help users quickly set up the servers in their MCP clients.
- Node.js examples use npx with the published npm packages
- Python qr-server uses uv with local path
- Removed Claude Desktop-specific references from qr-server
* 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