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explore / Backend & APIs / mozg / Deno

Deno · Reference

Answer questions from the Deno reference docs exactly as specified: every CLI command with its flags, the deno.json configuration fields, environment variables, and the runtime API surface.

1,158 notes · updated 2026-08-09 · trained 96%

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$ claude mcp add --transport http mozg \
https://mozg.sh/mcp --header "Authorization: Bearer …"
> use mozg/deno-reference — …
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Ask it things like

answers 44/46 on its latest exam
What does deno unlink do?CLI Commands - File Operations✓
What does the --check-js flag do when running deno check?CLI Commands - Flags & Options✓
What is the correct flag to install a package as a global binary with deno install?CLI Commands - Flags & Options✓
What is equivalent to running deno ci?CLI Commands - Workspace & Configuration✓
What does deno update do with workspaces?CLI Commands - Workspace & Configuration✓
How do I exclude files from linting in deno.json?Configuration - deno.json✓
What does DENO_DIR environment variable control?Environment Variables✓
What is Deno.serveHttp() now called?Runtime API - HTTP Server✓

What it can answer

46 coverage checks
96%
Answers 44 of the exam's 46 questions
✓CLI Commands - Flags & Options6 / 6
✓Runtime API - Removed/Changed6 / 6
▲Configuration - deno.json5 / 6
✓Environment Variables5 / 5
✓CLI Commands - Module & Dependency Management3 / 3
✓CLI Commands - Scripting3 / 3
✓CLI Commands - Workspace & Configuration3 / 3
✓Runtime API - TLS & Network3 / 3
▲CLI Commands - File Operations2 / 3
✓Compiler Configuration2 / 2
✓Format & Lint Comments2 / 2
✓Runtime API - Cryptography & Security2 / 2
✓Runtime API - HTTP Server2 / 2
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Attacks survived

re-run weekly · 2026-08-11
✓gate-battery12/12 known hostile payloads caught by the ingest gate
✓injection-corpusevery active note scanned — no steering language
✕secret-corpusConnection string with password: "deno deploy database link example" · Connection string with password: "deno deploy database link example" · Connection string with password: "deno deploy env add example" · Connection string with password: "deno deploy database management examples"

heuristic scans against known attack classes — measured and dated, not a promise of unpoisonability

Inside

  • location.href as base for relative URLs in fetch and Worker · api/globals
  • Worker communication between main thread and worker · api/globals
  • structuredClone and postMessage serializable types · api/globals
  • location global and --location flag · api/globals
  • Web Worker API only supports module type workers · api/globals
  • File locking advisory locks · api/file
  • fetch API supports file: URLs for local files · api/http
  • fetch spec deviations in Deno · api/http
  • structuredClone and postMessage transferable types · api/globals
  • CustomEvent and EventTarget spec deviations · api/globals
  • Web Storage API with 10MB limit · api/globals
  • localStorage unique storage location rules · api/globals
  • Web Worker top-level await pitfall with message handlers · api/globals
  • Worker instantiation permissions · api/globals

Licence

CC BY-NC-SA 4.0

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