Package as an Agent Plugin

[rbuchmayer-pplx]

Adds plugin.json and mcp.json so this repo installs as an Agent Plugin in clients that support the new standard (ChatGPT, Codex, Cursor, GitHub Copilot, Kiro, VS Code), matching what perplexityai/modelcontextprotocol#135 did for the MCP server repo.

One install gets the skills plus the docs MCP server (docs.perplexity.ai/mcp, streamable HTTP). No API key is needed for this plugin. The existing Claude Code and Codex packaging is unchanged.

Both manifests validate against the official 1.0.0 schemas, and I verified an end-to-end install with the Codex CLI.

[qirh]

LGTM — manifests validate against the 1.0.0 schemas and the CI mirrors modelcontextprotocol#136. Two notes, follow-up PR incoming for the mechanical one:

• Root plugin.json has no version while .codex-plugin/plugin.json says 0.3.0 — adding version + a sync check in a stacked PR.
• Worth confirming intent: mcp.json ships only the docs MCP, so the official plugin doesn't expose the main Perplexity MCP server tools. Fine if keyless install is the goal, but the thread implied the plugin would point at it. (Also assuming the displayName removal in marketplace.json is a strict-validation fix.)

[rbuchmayer-pplx]

Intentional. After that thread, the search MCP got its own plugin in perplexityai/modelcontextprotocol#135, so this one is deliberately skills + docs MCP only. Duplicating the search server here would mean double tools for anyone who installs both, and it would break the keyless install for this plugin (docs MCP needs no key, the search server does).

And ya, displayName was a strict-validation fix: claude plugin validate rejects the key, installs just tolerated it.