• Interchange — validate and generate harness config without hand-copying paths per tool.
• Transform — pure functions map VHF to .claude/, .cursor/, .opencode/, .pi/, etc., with merge policies for JSON (MCP, hooks).
• Extend — third-party bundles can ship VHF-shaped artifacts and reuse the same validators and transformers the CLI uses.

npm install @viper-ai/harness

import { readFile } from 'node:fs/promises';
import { parseSkillMarkdown } from '@viper-ai/harness';

const raw = await readFile('artifacts/skills/my-skill/SKILL.md', 'utf8');
const result = parseSkillMarkdown(raw, { path: 'my-skill/SKILL.md' });

if (!result.ok) {
  console.error(result.errors.join('\n'));
  process.exit(1);
}

console.log(result.data?.frontmatter.name, '— OK');

import {
  getTransformerForTarget,
  applyTargetWrites,
  type HarnessArtifact,
} from '@viper-ai/harness';

const root = process.cwd();
const artifacts: HarnessArtifact[] = [/* your VHF artifacts */];
const target = 'cursor';

const transform = getTransformerForTarget(target);
const writes = transform(artifacts, { root, target, force: false });

await applyTargetWrites(root, writes, false);
console.log(`Wrote ${writes.length} paths under ${root}`);