bot-agents/.agents/memory/ts-only-files-and-imports.md

description

description
Every file is .ts (no js/mjs/cjs/jsx/tsx, configs included) and source imports only .ts; CSS comes from HTML, JSON/SVG become .ts modules

The user's rule, from the Deno days and restated for Node (2026-10-12): "No JS, not even JSX/TSX, only TS." Source, scripts, tests, and configs are all plain .ts. Build output in a gitignored folder is the only JS.

tsconfig.json: no allowJs, no jsx, and the template's strict flags (verbatimModuleSyntax, erasableSyntaxOnly, allowImportingTsExtensions, isolatedDeclarations in packages, exactOptionalPropertyTypes, noUncheckedIndexedAccess). If a tool or framework seems to need a JS or TSX file, stop and flag it instead of adding one.

Only .ts imports (2026-10-14)

project/no-non-ts-imports (in scripts/project-lint.ts) fails:

• a relative, absolute, #, or package-subpath specifier whose last segment has a non-.ts extension: .css, .json, .svg, .js, .mjs, .tsx;
• any ?query suffix (?raw, ?url, ?inline);
• any import attributes (with { type: "json" }, with { type: "text" }).

Bare packages (lit, @types/json-schema, lodash.debounce), # aliases, and node: builtins pass. @fortawesome/x/svgs/a.svg fails.

import "./theme.css"; // no
import data from "./scenes.json" with { type: "json" }; // no
import icon from "./lock.svg?raw"; // no
import { scenes } from "#data/scenes"; // yes: scenes.ts

What to do instead

• CSS: load it from HTML with <link rel="stylesheet" href="...">. Never import CSS from TS, not even for Vite. (This also removes most of the import/no-unassigned-import hits the suspicious category reports.)
• JSON data: turn it into a .ts module exporting a typed constant.
• SVG: a .ts module exporting a Lit template; see icons-memona-style.
• package.json fields at runtime: never import pkg from "./package.json" and there is no #package alias. Write the value out in .ts and add a test in tests/ that reads package.json with node:fs and fails on drift (the plugin repos do this for meta.name/meta.version).
• Reading a file is not importing it. readFileSync + JSON.parse is fine in tooling and tests.
• A tool's .js entry: don't import("pkg/cli.js"); use the package entry or spawn the package's bin (lit-analyzer-ts6).