# Openhands Foundation

> Use when building or porting an agent-chat frontend or the OpenHands Agent Canvas UI runtime — resumable dual-socket WebSocket event streams with REST-preload gating, rAF delta coalescing, id-dedup replay handling, optimistic message queues with server-echo matching, replay-safe client-action dispatch, reconnect ladders for parallel sockets, cron-preset automation schedules, browser-executed client tools with exactly-once launch ledgers, backend-split REST services with compensating import transactions, scoped query-cache invalidation, contract-fixture MSW mock fleets, desktop boot-splash launch chains, bootstrap version gates, local dev-stack launch orchestration, read-only terminal projection, rate-budgeted run-health dashboards, multi-backend selection with persisted health disable-latches, prompt-injection git controls, cookie-minted workspace file previews, host-login ACP auth probes, and manifest-owned command palettes.

- Skill: `ryan-brosas/openhands-foundation` (Agent Skill, multi-file: 25 files)
- Install (CLI): `npx skillmds@latest add ryan-brosas/openhands-foundation`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ryan-brosas/openhands-foundation/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: ryan-brosas (https://skillmd.com/u/ryan-brosas)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/ryan-brosas/openhands-foundation

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# OpenHands (Agent Canvas): agent-conversation UI runtime foundation

## Foundation contract

This is a cold, source-specific foundation, not an operational procedure. It is
historical, revision-pinned evidence rather than timeless guidance. Current
project source, tests, requirements, and runtime behavior outrank this
projection and decide what ships.

## Provenance and revision

- Source record: `openhands`; portable upstream identity, license, coverage caveats, and retrieval history are preserved in the index.
- Recorded revision: `main@8511fff62d3084587cda1add483fe5ea9c8bfd7e`.
- Full provenance, coverage caveats, boundaries, and preserved evidence:
  `references/index.md`.

## Topic map

- Representative topics: Conversation stream kernel; Reconnect ladder; Delta
  batcher; Event store; Optimistic queue; Cron preset mapping; Client-tool
  round trip; Dev-stack orchestrator.
- Scope and retrieval questions: `references/index.md#use-this-for`.
- Complete capsule chooser: `references/index.md#load-the-matching-source-dump`.
- Detailed grouped map: `references/index.md#capsule-map`.
- Source limitations and portability boundaries: `references/index.md#boundaries`.

## Retrieval

Open the index, choose one capsule matching the active question, and load only
that capsule. Revalidate its cited source and revision before relying on it. Do
not bulk-load the inventory, treat historical claims as current truth, or apply
this foundation as a procedure.