Subagents — ap-sdk

Subagents package a focused prompt under a name so the primary agent can delegate. Claude and OpenCode receive markdown agents, Codex receives developer instructions, and unsupported harnesses emit warnings.

plugin.ts

import { definePlugin, defineSubagent } from "@jalco/ap-sdk";

export default definePlugin({
  id: "review-team",
  description: "Specialist review agents.",
  subagents: [
    defineSubagent({
      name: "security-reviewer",
      description: "Reviews diffs for auth, secrets, and injection risks.",
      prompt: "You are a security reviewer. Lead with blockers.",
      tools: ["Read", "Grep", "Bash"],
      harness: {
        claude: { model: "sonnet" },
        codex: { model: "gpt-5" },
        opencode: { model: "gpt-5", mode: "subagent" },
        gemini: { model: "gemini-3-pro", temperature: 0.2, maxTurns: 8 },
        copilot: { model: "gpt-5" },
      },
    }),
  ],
});

Fields

name and description identify and route the agent.
prompt maps to Claude/OpenCode body text and Codex developer_instructions.
tools is honored by Claude Code.
frontmatter is emitted for YAML-frontmatter harnesses; Codex TOML ignores it.
harness sets target-specific model and behavior hints, including Gemini temperature / maxTurns and OpenCode mode (primary, subagent, all).

Next: hooks and the support matrix.