/AGENTS.md

claude-agents — multi-harness agentic plugin marketplace

Production-ready agentic-workflow building blocks: 94 plugins (90 local + 4 external), 203 agents, 175 skills, 109 commands. Native source-of-truth for Claude Code; also consumed by OpenAI Codex CLI, Cursor, OpenCode, and Gemini CLI from a single Markdown source.

This file is the canonical context file. Codex / Cursor / OpenCode read it directly. Claude Code reads it via CLAUDE.md, a symlink to this file. Gemini CLI reads it via gemini-extension.json (contextFileName) / .gemini/settings.json.

Read this file like a table of contents. Detail lives in docs/. Authoring conventions live in docs/authoring.md. Per-harness setup and capability deltas live in docs/harnesses.md. Gemini-specific setup is in GEMINI.md (also auto-loaded by Gemini CLI). This file should never grow beyond ~150 lines (per OpenAI's harness-engineering practice).

Map

• ARCHITECTURE.md — top-level architectural overview (adapter framework, source-of-truth invariant, capability matrix summary)
• docs/architecture.md — detailed design principles
• docs/plugins.md — full plugin catalog (94 plugins by category)
• docs/agents.md — agent reference (203 agents, model tiers)
• docs/agent-skills.md — skill reference (progressive disclosure model)
• docs/usage.md — commands, workflows, examples
• docs/authoring.md — portable-content style guide (read before adding plugins)
• docs/harnesses.md — per-harness capability matrix
• docs/plugin-eval.md — three-layer quality evaluation framework
• docs/round-trip-results.md — real-CLI verification recipes
• CONTRIBUTING.md — how to contribute

Working in this repo

• Python tooling: uv (package manager), ruff (lint/format), ty (type check). Do not use pip / mypy / black.
• Plugins live under plugins/<name>/ with auto-discovery — see docs/authoring.md for frontmatter shapes.
• Plugin names: lowercase, hyphen-separated. Never use __ (it's the adapter namespace separator).
• Never commit secrets. Never run destructive git (force-push, reset --hard, branch -D) without explicit ask.

Quality gates (run these before pushing)

make validate STRICT=1     # structural validation across all harness outputs
make garden                # drift detection (dead links, stale artifacts, oversize skills)
make test                  # full pytest suite (plugin-eval + tools/tests/)
make smoke-test            # real-CLI subprocess tests against generated artifacts

CI (.github/workflows/validate.yml) runs all four on every PR plus installs OpenCode + Gemini CLI for live verification.

Regenerating per-harness artifacts

make generate HARNESS=codex      # .codex/skills, .codex/agents, .codex/plugins/<p>/, .agents/plugins/marketplace.json
make generate HARNESS=cursor     # .cursor-plugin/{marketplace,plugin}.json, .cursor/rules/
make generate HARNESS=opencode   # .opencode/{skills,agents,commands,plugins}/, opencode.json
make generate HARNESS=gemini     # skills/, agents/, commands/ at extension root
make generate-all                # all four

Generated artifacts are committed so each harness installs natively from a clone / GitHub URL (native-install commands in docs/harnesses.md). Run make generate-all before committing source changes — CI fails on drift. Source-of-truth lives only under plugins/; never hand-edit generated files.

Skills (cross-harness)

175 skills under plugins/*/skills/<n>/SKILL.md — discoverable by every harness:

• Claude Code: auto-discovery via Anthropic's SKILL.md spec
• Codex CLI: mirrored to .codex/skills/<plugin>__<skill>/ (8 KB body cap; detail in references/details.md)
• OpenCode: mirrored to .opencode/skills/<plugin>-<skill>/ using hyphenated names for global install
• Cursor: reads .claude/skills/ directly (no re-emit)
• Gemini CLI: native skills at skills/<plugin>__<skill>/SKILL.md

Top-level skills/ is Gemini output; do not use it for OpenCode installs.

Subagents (cross-harness)

203 subagents under plugins/*/agents/<name>.md. Per-harness transpilation:

• Codex: .codex/agents/<plugin>__<agent>.toml (drop tools:, map model alias to the GPT-5.x family, infer sandbox_mode)
• OpenCode: .opencode/agents/<plugin>__<agent>.md with mode: subagent + permission: block (locked agents — those with source tools: [] — get deny-everything except base skill/task)
• Gemini: agents/<plugin>__<agent>.md (April 2026 subagent spec)
• Cursor: reads .claude/agents/ directly

Why this file is short

Per OpenAI's harness-engineering practice: this file is a map, not an encyclopedia. Procedural detail lives in skills (loaded on demand by agents). Reference material lives in docs/ (loaded when an agent navigates). A single bloated AGENTS.md crowds out the task, rots quickly, and is hard to verify mechanically. Keep it lean; push detail elsewhere.