[FEATURE] Support Agent Plugins 1.0 (agent-plugins.org) as a first-class plugin format

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Summary

OpenCode already supports most of the core building blocks required by the Agent Plugins 1.0 specification (https://agent-plugins.org):

• Skills — OpenCode can discover and execute agent skills
• Agents / Subagents — including permissions and tool restrictions
• MCP Servers — both local and remote (e.g. {"mcp":{"jira":{"type":"remote","url":"https://example.com/mcp"}}})
• Agent configuration and organizational distribution through remote configuration

However, OpenCode currently lacks support for the Agent Plugins packaging format, which has become the emerging vendor-neutral standard for distributing reusable AI agent capabilities across tooling ecosystems.

The Agent Plugins specification was created specifically to standardize packaging and discovery of:

• Agent Skills
• MCP Servers

while allowing vendors to extend functionality through client-specific namespaces.

Reference: https://agent-plugins.org

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Why this matters

Today, users must manually configure skills directories, MCP server definitions, agents, and organizational defaults inside OpenCode.

The Agent Plugins specification provides a common packaging layer that allows these resources to be bundled and distributed as a single portable unit.

This is especially valuable because support for Agent Plugins is already appearing across major agent ecosystems such as:

• VS Code / GitHub Copilot — https://code.visualstudio.com/docs/agent-customization/agent-plugins
• Claude Code — https://code.claude.com/docs/en/plugins
• Devin
• Codex

As a result, the same skills and MCP servers can be reused across multiple clients.

Without Agent Plugins support, plugin authors must maintain OpenCode-specific installation instructions even when their portable skill and MCP definitions already conform to the standard.

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Current OpenCode capabilities

Skills

OpenCode can discover and execute agent skills.

MCP Servers

OpenCode supports both local and remote MCP servers:

{
  "mcp": {
    "jira": {
      "type": "remote",
      "url": "https://example.com/mcp"
    }
  }
}

Agents

OpenCode already supports:

• Primary agents
• Subagents
• Permissions
• Tool restrictions

These capabilities indicate that most of the runtime infrastructure required for Agent Plugins already exists — what's missing is the packaging/discovery layer.

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Proposed implementation

1. Detect plugin manifests

Detect and parse plugin.json (or equivalent) manifests from:

• A designated plugins directory (e.g. ~/.opencode/plugins/ or a project-local .opencode/plugins/)
• Remote plugin registries (configurable via opencode.json)
• Git repositories (install via URL)

2. Load skills

Automatically discover skill definitions bundled in the plugin and register them in OpenCode's existing skill discovery path.

3. Load MCP definitions

Automatically load MCP server definitions from the plugin manifest into OpenCode's existing MCP configuration, so plugin-bundled servers work without manual opencode.json edits.

4. Ignore unsupported extensions

The Agent Plugins specification intentionally allows client-specific extensions via namespaces. OpenCode should ignore namespaces/extensions it doesn't understand (rather than failing), and log them at debug level for troubleshooting.

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Benefits

For users

• Single installable unit (one plugin = skills + MCP + config)
• Easier sharing across teams
• Less manual configuration
• Better portability across agent platforms

For plugin authors

• One plugin works across multiple agent platforms (VS Code, Claude Code, Devin, Codex, OpenCode)
• Less client-specific packaging
• Reduced maintenance burden

For OpenCode

• Alignment with emerging ecosystem standards
• Interoperability with existing plugin marketplaces
• Easier enterprise adoption (standardized distribution)

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Compatibility

This proposal should be largely additive and backward-compatible.

Existing skills, MCP configuration, and agents would continue working unchanged. Agent Plugins would simply provide a portable discovery mechanism on top of the existing capabilities — no breaking changes to current workflows.

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References

• Agent Plugins Specification — https://agent-plugins.org
• VS Code Agent Plugins — https://code.visualstudio.com/docs/agent-customization/agent-plugins
• Claude Code Plugins — https://code.claude.com/docs/en/plugins
• OpenCode MCP Documentation — https://opencode.ai/docs/mcp-servers/
• OpenCode Agents Documentation — https://opencode.ai/docs/agents/