Yichen Jiang
ea4c10d753
Review discussion converged on the industry shape (Claude Code caches user context per conversation; Codex separates initial context from diffs; Kimi appends at continuation boundaries to protect prompt caching): stable openers belong in a compose-once prefix, mid-session changes belong in append-only history — not in a per-request slot. agent/session-prefix fires ONCE per loop instance, lazily on its first request-building step: the composed Message[] is deep-frozen, cached on the transmission bookkeeping, recorded as EpochHeader.messagePrefix on the anchoring 'initial'/'resume' snapshot, and reused verbatim for every request the instance sends — prefix stability is structural, not a producer discipline, and a resume recomposes with attributable drift. The request is messagePrefix + boundary snapshot. The per-step RequestAdvice/RequestAdviceContext surface and the messageSuffix header field are dropped: the tail slot had no consumer, and every current update pattern (new AGENTS.md discovered, memory update, skills change) routes through the existing append-only history channels — inject(), tools/post-execute additionalContext, prompt-submit additionalContext — each paid once and prefix-cached thereafter. The messagePrefix delta arm stays for codec totality; the loop never produces one in practice.
DeepSeek Harness
English | 中文
The DeepSeek Harness SDK is a plugin-based SDK for building agent harnesses.
Development
This monorepo is built on the Cordis framework (vendored as source under vendor/), microkernel-style: everything is a plugin.
pnpm install
pnpm run test # vitest
pnpm run demo:repl # REPL agent demo (needs DEEPSEEK_API_KEY)
pnpm run demo:acp # ACP server agent demo (needs DEEPSEEK_API_KEY)
For humans, start with the development guide for local setup, hooks, environment variables, and quality gates, then read the architecture design and documentation graph index before package work. Local context lives in packages/ and vendor/.
For agents, follow AGENTS.md.