[paulocastellano]

What this PR does

New plugin: adds TryPost, a social media scheduling skill + hosted MCP server for drafting, scheduling, publishing, previewing, and tracking posts across Instagram, Facebook, LinkedIn, X, TikTok, YouTube, Threads, Pinterest, Bluesky, Mastodon, Telegram, and Discord.

• Plugin name: trypost
• Type: remote source
• Source URL + pinned SHA (remote): https://github.com/trypostit/trypost-agent.git @ 9f619fe6a07037b519d56688df965ec6b8720df9 (v1.0.0)
• Homepage: https://trypost.it

Ownership

• I own this plugin or have the right to distribute it.
• The source repo is published under our official org (or I've explained why not below).

Checklist

• Added/updated exactly one entry in .grok-plugin/marketplace.json (valid JSON, kebab-case name).
• Remote source pins a full 40-char lowercase commit sha, and that commit is public + reachable.
• Regenerated .grok-plugin/plugin-index.json (python3 scripts/generate-plugin-index.py).
• python3 scripts/validate-catalog.py passes locally.
• python3 scripts/generate-plugin-index.py --check passes locally.
• homepage + clear description set; local plugins include README.md + .grok-plugin/plugin.json.
• License is stated (AGPL-3.0, declared in the plugin's plugin.json and repo LICENSE).

Security

• No curl | bash, remote-code download/exec, or postinstall RCE.
• No reading/exfiltration of secrets, tokens, .env, or env vars.
• Hooks and MCP scope are least-privilege.
• Network endpoints this plugin calls (and why): the plugin declares one MCP server via mcpServers in its .grok-plugin/plugin.json — https://app.trypost.it/mcp/trypost (streamable HTTP, OAuth; the user signs in to TryPost on first connection, nothing runs locally and no token is stored by the plugin). The skill only instructs the agent to call those MCP tools.
• Credentials/permissions it requires (and why): an OAuth login to the user's own TryPost account (scoped to their workspace via the mcp:use grant). No API key, env var, or local credential is read or stored by the plugin.

Notes for reviewers

TryPost is an open-source social media scheduling platform (https://github.com/trypostit/trypost). The plugin repo is under our official trypostit org, and I'm the founder/maintainer. The plugin is a single skill plus the official hosted TryPost MCP server declared in the manifest — no CLI, no local binaries, no hooks.

Update: bumped the pin to 9f619fe after merging author email (paulo@trypost.it) and homepage (https://trypost.it) on trypost-agent main. Index regenerated and both validators re-run locally.