Report · marked 25 Aug 2026
microsoft/monaco-editor
An agent can work here, but it will waste turns finding its footing.
JavaScript · 46,587 stars · 994 files · branch main
62
/100
B
Instructions
3/27Whether the repo tells an agent how to behave before it starts guessing. Losing marks on agent instruction file and instruction quality.Setup
16/16Whether an agent can install the project and get it running without a human. Full marks.Verification loop
19/25Whether an agent can check its own work. This is the category that most decides whether agent output is trustworthy. Losing marks on lint and format rules and static type checking.Context economy
13/20Whether the repo fits in a context window, or fights it. Losing marks on file sizes fit in context and repository weight.Navigability
10/10How quickly anything new can orient itself. Full marks.
Higher is better. Accent marks what is costing you most.
Fix these first
01
Agent instruction file
Add an AGENTS.md at the root: what the project is, how to install, how to run, how to test, and the two or three conventions a newcomer always gets wrong.
02
Instruction quality
Instructions earn their keep by naming exact commands. 'Run the tests with `pnpm test`' beats three paragraphs of philosophy.
03
File sizes fit in context
A single file that fills the context window forces an agent to work from fragments, and it will confidently edit code it never saw. Splitting the worst offenders pays for itself immediately.
The full marking
Every deduction below names the file or setting it came from.
Instructions 3/27 F
Whether the repo tells an agent how to behave before it starts guessing.
✗Agent instruction file
0/12
None found. Every agent that opens this repo starts from zero.
Add an AGENTS.md at the root: what the project is, how to install, how to run, how to test, and the two or three conventions a newcomer always gets wrong.
Looked for AGENTS.md, CLAUDE.md, .github/copilot-instructions.md, .cursorrules
✗Instruction quality
0/12
Nothing to judge, since there are no instructions.
Instructions earn their keep by naming exact commands. 'Run the tests with `pnpm test`' beats three paragraphs of philosophy.
✓README as an entry point
3/3
README has a clear getting-started section.
Setup 16/16 A+
Whether an agent can install the project and get it running without a human.
✓Deterministic install
6/6
package-lock.json pins the dependency tree.
Found package-lock.json
✓Discoverable commands
6/6
Commands are declared where an agent will look for them.
package.json scripts (import-typescript, postinstall, prettier-check, prettier, pretty-quick, simpleserver…)
–Environment config
n/a
Not applicable — this reads as a library, with no environment to configure.
✓Pinned runtime version
2/2
The language runtime version is pinned.
Found .nvmrc
✓Reproducible environment
2/2
.devcontainer/devcontainer.json gives a known-good environment.
Verification loop 19/25 B+
Whether an agent can check its own work. This is the category that most decides whether agent output is trustworthy.
✓Tests exist
8/8
134 test files against 616 source files.
e.g. src/languages/definitions/abap/abap.test.ts, src/languages/definitions/apex/apex.test.ts, src/languages/definitions/azcli/azcli.test.ts
✓Test command is discoverable
7/7
An agent can find and run `npm run test`.
✓Continuous integration
4/4
2 GitHub Actions workflows define what "passing" means.
✗Lint and format rules
0/3
No linter or formatter config. Style is tribal knowledge, so agent output will drift from yours.
A formatter config is the cheapest way to stop reviewing whitespace in agent diffs. It moves style from opinion to a command.
✗Static type checking
0/3
No static type checking.
A type checker gives an agent an error message instead of a runtime surprise. It's the second-fastest feedback loop after the compiler.
Context economy 13/20 B
Whether the repo fits in a context window, or fights it.
✓No committed build output
6/6
No generated directories committed.
✓.gitignore hygiene
3/3
.gitignore covers 8 patterns.
✗File sizes fit in context
0/6
11 source files are over 100KB.
A single file that fills the context window forces an agent to work from fragments, and it will confidently edit code it never saw. Splitting the worst offenders pays for itself immediately.
src/languages/features/typescript/lib/typescriptServices.js — 8900KB
src/languages/features/typescript/lib/lib.ts — 3144KB
src/languages/features/typescript/lib/typescriptServices.d.ts — 574KB
✗Repository weight
4/5
About 140.0MB checked out, which is comfortable.
Here is your AGENTS.md
Drafted from what is actually in this repository: the install
command from your lockfile, the commands you already declare, your real directory layout. Anything
marked TODO needs a person. Save it at the root as AGENTS.md.
# AGENTS.md A browser based code editor ## Setup ``` npm ci ``` ## Commands ``` npm run build # produce a build npm run test # run the test suite, must pass before any commit npm run import-typescript npm run postinstall npm run prettier-check npm run prettier npm run pretty-quick npm run simpleserver ``` ## Layout - `src/` 428 source files - `website/` 78 source files - `monaco-lsp-client/` 33 source files - `samples/` 27 source files - `build/` 23 source files - `test/` 17 source files ## Conventions - Tests live alongside the code they cover, following `src/languages/definitions/abap/abap.test.ts`. - CI defines what passing means. See `.github/workflows/ci.yml`, and keep it green. - TODO: add the two or three conventions a newcomer always gets wrong here. ## Gotchas - Generated output is committed (`build/`). Search will return the compiled copy, so edit the source, not that. - `src/languages/features/typescript/lib/typescriptServices.js` is 8900KB. It will not fit comfortably in context, so read it in parts. --- Drafted by agentreadme.com from what is in this repository. Everything marked TODO needs a human. Check it in as AGENTS.md at the root.
Open the raw markdown
or
curl -o AGENTS.md agentreadme.com/draft/microsoft/monaco-editor.md
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Think this mark is wrong?
Every deduction above names the file it came from, so this can be settled by looking. If a check missed something, that is a rule worth fixing.