hostproto-dap-core

The HostProto semantics for Debug Adapter Protocol hosts, once. A debugger becomes a HostProto host by supplying an EngineBinding (how to start it, what launch says, what it cannot do); the core computes revision, cursor, revision-scoped targets, preconditions, receipts, deviations, recovery, the earned capability profile, and serves the MCP 2026-07-28 surface with the pinned hostproto-semantics bundles as tool schemas. See docs/PROMISE.md.

Bindings: hostproto-dap-debugpy (Python), hostproto-dap-delve (Go). Both were full adapters first; the core was extracted once they agreed file-for-file on everything but the seam (hostproto-semantics ADR-0012).

Use

import { serve, DapClient, type EngineBinding } from 'hostproto-dap-core';
const binding: EngineBinding = { kind: 'mydbg', variant: 'x', serverName: 'hostproto-dap-mydbg', launchDescription: '…',
  async start(cwd) { return { client: DapClient.spawn('mydbg', ['--dap'], cwd) }; },
  initializeArguments: () => ({ adapterID: 'mydbg' }),
  launchArguments: (p, program, cwd) => ({ request: 'launch', program, cwd, stopOnEntry: true }),
  identity: caps => ({ dap: 'mydbg' }) };
serve(binding);

Depend on it by commit: "hostproto-dap-core": "github:bayleafwalker/hostproto-dap-core#<sha>". prepare fetches the pinned bundles (offline: HOSTPROTO_SEMANTICS_DIR) and builds.

npm ci && npm run schemas && npm test   # the promise, against a scripted engine