new·The score now tells you which way it movedA brain's exam only ever grows: its own material writes questions, and so does every question a real caller asked and did not get answered. The score is a percentage over that growing set, so a brain that learned more could post a smaller number — and this week three did. One of them answered two MORE questions than the week before and showed eighteen points less. Printed as a single percentage, that reads as decline to a reader and as punishment to anyone who contributes material.all news →
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Deno

Answer questions about the Deno runtime as documented today: the permission model and its flags, the CLI commands and their options, configuration with deno.json, Node and npm compatibility, testing, linting and formatting, and the runtime APIs — Deno 2 behaviour, not Deno 1.

2,225 notes across 3 brains · updated 2026-08-12 · trained 87%

since last sitting: +75 newly passed — this brain is learning · the verified changelog →

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

answers 67/75 on its latest exam · anti-bluff 8/13
What permission flag must be used to read files from the file system?Permissions model and flags✓
What is the default glob pattern used by `deno test` to find test files?CLI commands and options✓
How would you grant read permission to only a specific directory?Permissions model and flags✓
Can you describe what the NotCapable permission error means and which flag typically needs to be added?Permissions model and flags✓
What is the recommended way to serve HTTP requests in Deno 2?Runtime APIs✓
What replaced Deno.run() in Deno 2?Runtime APIs✓
What is the command to run tests in Deno?Testing and linting✓
What does the `--target` flag do in `deno compile`?CLI commands and options✓

What is inside

asking this brain searches all 2
Deno · FundamentalsAnswer questions from the Deno fundamentals and getting-started docs: the security and permission model, modules and imports, the runtime Web APIs, workspaces, and running scripts with the exact flags.371 notes92%Deno · ReferenceAnswer 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.1158 notes96%

What it can answer

75 coverage checks
87%
Answers 75 of the exam's 88 questionsIt answers 75 questions, 75 more than last time, out of an exam that grew by 88.Nothing it used to answer has stopped working.
▲CLI commands and options17 / 20
▲Runtime APIs12 / 13
✓Permissions model and flags10 / 10
✓Miscellaneous Deno 2 features9 / 9
▲Configuration with deno.json7 / 9
✓Testing and linting7 / 7
▲Node and npm compatibility5 / 7
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Attacks survived

re-run weekly · 2026-08-11
✓gate-battery12/12 known hostile payloads caught by the ingest gate
✕injection-corpusExfiltration ask: "Debug authentication tokens with deno run -L debug"
✓secret-corpusevery active note scanned — no keys or credentials

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

Inside

  • no-sloppy-imports example valid imports · cli: lint
  • no-sloppy-imports only active with --unstable-sloppy-imports flag · cli: lint
  • no-sloppy-imports example invalid imports · cli: lint
  • no-sloppy-imports lint rule requires explicit file extensions · cli: lint
  • no-setter-return rule disallows returning values from setters · cli: lint
  • no-setter-return invalid examples · cli: lint
  • no-setter-return valid early return pattern · cli: lint
  • jsx-boolean-value rule enforces consistent JSX boolean syntax · cli: lint
  • jsx-boolean-value is a recommended rule · cli: lint
  • getter-return lint rule requires return value · cli: lint
  • getter-return valid example - class getter with return · cli: lint
  • getter-return valid example - object getter with return · cli: lint
  • getter-return invalid example - object getter · cli: lint
  • getter-return invalid example - class getter · cli: lint

Licence

CC BY-NC-SA 4.0

Use it, copy it, build on it, with credit. Selling it is not allowed.