vendor-adapters

name	vendor-adapters
description	Master cross-vendor reference for LLM vendor harness formats — complete format mapping tables, documentation URLs, known gaps, and the workflow for keeping references current.

This is the single source of truth for how harness artifacts map across Claude Code, Cursor, and Codex. Use it when comparing vendor behavior, checking format compatibility, or running a vendor sync update.

Vendor Documentation URLs

Claude Code (Anthropic)

Area	URL
CLI Reference	https://code.claude.com/docs/en/cli-reference
Plugins Overview	https://code.claude.com/docs/en/plugins
Plugins Reference	https://code.claude.com/docs/en/plugins-reference
Plugin Marketplaces	https://code.claude.com/docs/en/plugin-marketplaces
Hooks Guide	https://code.claude.com/docs/en/hooks-guide
MCP Servers	https://code.claude.com/docs/en/mcp
Settings Reference	https://code.claude.com/docs/en/settings
Subagents	https://code.claude.com/docs/en/sub-agents
Official Plugins Repo	https://github.com/anthropics/claude-plugins-official

OpenAI Codex

Area	URL
Plugins Overview	https://developers.openai.com/codex/plugins
Plugin Build Guide	https://developers.openai.com/codex/plugins/build
Hooks	https://developers.openai.com/codex/hooks
CLI Reference	https://developers.openai.com/codex
GitHub Repo	https://github.com/openai/codex
Hook Schemas	https://github.com/openai/codex/tree/main/codex-rs/hooks/schema/generated

Cursor

Area	URL
Plugin Template	https://github.com/cursor/plugin-template
Official Plugins Repo	https://github.com/cursor/plugins
Marketplace	https://cursor.com/marketplace
MCP Servers	https://docs.cursor.com/advanced/mcp
Rules (.mdc)	https://docs.cursor.com/advanced/rules
CLI	https://cursor.com/cli
Forum: .agents/ support	https://forum.cursor.com/t/support-for-agent-folder-compatibility/154167

Cross-Vendor Standards

Area	URL
Agent Skills	https://agentskills.io
AGENTS.md Spec	https://github.com/agentsmd/agents.md
.agents/ Folder Spec	https://github.com/agentsfolder/spec
MCP Spec	https://modelcontextprotocol.io/specification/2025-03-26

Vendor Support Matrix

Quick-lookup: what each vendor supports. For format details see references/.

Artifact	Claude Code	Cursor	Codex
Skills	✓ full	✓ full	✓ full
SubAgents	✓ full	~ partial (research needed)	✗ not in plugins
MCP	✓ stdio + HTTP	✓ stdio + SSE + OAuth	✓ stdio only
Hooks	✓ 25 events, 4 types	✓ 25 events, 2 formats	~ 5 events, command only (experimental)
Startup Context	✓ CLAUDE.md + rules/	✓ .cursor/rules/*.mdc	✓ AGENTS.md only
Rules in plugins	✓ .claude/rules/*.md	✓ .mdc with frontmatter	✗ not supported
Commands	✓ legacy (prefer skills)	✓ commands/*.md	✗ not supported

Format Mapping Tables

(See references/ directory for full format details — anthropic.md, cursor.md, codex.md)

Known Gaps

Track gaps in references/vendor-*.md files. Each gap entry:

• Priority: HIGH / MED / LOW
• Description: what's wrong or missing
• Vendor: which vendor
• Status: OPEN / RESOLVED (with resolution note)

Update Workflow

When vendor documentation changes:

1. Use fetch-vendor-docs skill to retrieve current docs from URLs above
2. Compare against stored references in this skill's references/ directory
3. Identify: what changed, what's new, what was removed
4. Update affected reference files
5. Use flag-vendor-gaps skill to update gap table