Disclosure up front: I build dropspace, one of the six tools below. I've tried to keep every claim about the others to what their own docs and pricing pages say, with links, and I've marked what I couldn't verify.
What I was looking for
I wanted an agent to publish the same announcement to several social platforms without me wiring up an OAuth flow, a media upload API, and a rate limiter for each one. That gives four questions for any posting API:
- Can a new developer get API access today, and on which plan?
- Is there an MCP server, so an agent can use it without custom glue?
- What does the cheapest useful tier cost?
- Can an agent pay per post without a human creating an account first?
The comparison
| API access | MCP server | Cheapest tier | Open source | |
|---|---|---|---|---|
| Buffer | Every plan, including Free | Yes | Free: 1 API key, 3,000 requests per 30 days | Not verified |
| Ayrshare | Yes | Not verified | Priced per managed social profile | Not verified |
| Blotato | Paid plans only (the 7-day trial excludes API and MCP) | Yes, hosted | $29 a month, 20 connected accounts | Not verified |
| Postiz | Yes | Yes, hosted | $29 a month, 5 channels; free if you self-host | Yes, AGPL-3.0 |
| Zernio | Yes | Not verified | $48 a month shown on the pricing page | Not verified |
| dropspace | Every plan, including Free | Yes, npm or hosted | Free: 5 launches a month | No |
Sources: Buffer API docs, Ayrshare pricing, Blotato for AI agents, Postiz pricing, Zernio pricing, dropspace docs. Prices are as listed in November 2026; check the pages before you commit.
Where each one fits
Buffer is the safe choice if you already schedule posts there. The API comes with the free plan and there is an MCP server. The free limits (1,000 requests per connected channel per 30 days, 3,000 in total) are fine for a personal agent and tight for a product.
Ayrshare is built for products that post on behalf of their own users. It covers the most mainstream networks of this group, including Pinterest, Telegram, Bluesky, Snapchat, Google Business Profile, and Threads. Pricing scales with the number of profiles you manage, and posting to X may need your own X developer account.
Blotato bundles posting with content creation and has a hosted MCP server. The trial doesn't include the API or MCP, so you pay $29 before your agent can make its first call.
Postiz is the one to pick if you want to own the stack. It is AGPL-licensed, covers the longest list of destinations (including Mastodon, Discord, Dev.to, and Hashnode), and has a hosted MCP server. Self-hosting means you also apply for each network's developer app approval yourself.
Zernio combines posting and direct messages in one API, with 10,000 sent DMs a month included before metering. X API charges are passed through at cost.
dropspace is the one I build, so weigh this accordingly. It covers 10 platforms: X, Instagram, TikTok, LinkedIn, Facebook, Reddit, YouTube, and Substack are posted for you, and Product Hunt and Hacker News are guided, meaning it writes the content and you post it by hand. Two things are different from the rest of this list:
- The hosted MCP endpoint answers
initializeandtools/listwithout a key, so an agent or a directory can see what the server does before anyone signs up. - An agent can pay per launch with no account at all, using x402: $0.55 a launch in USDC after 5 free a month per wallet.
Adding it to Claude Code is one command:
claude mcp add --transport http dropspace https://api.dropspace.dev/mcp \ --header 'Authorization: Bearer YOUR_API_KEY' From there the agent creates a launch, optionally has per-platform copy generated, and publishes it. The REST equivalents are POST /launches and POST /launches/{id}/publish.
What dropspace doesn't do
- Fewer destinations than Postiz or Ayrshare. No Pinterest, Threads, Bluesky, or Mastodon.
- Not open source, so no self-hosting.
- No direct messages. If you need DMs, look at Zernio.
How I'd choose
- Already on Buffer, low volume: stay on Buffer.
- Posting for your own users across many networks: Ayrshare.
- Want to self-host or need niche destinations: Postiz.
- Need DMs with posting: Zernio.
- Building an agent that should discover the tool, post, and pay by itself: dropspace.
If I've got a fact about one of the other tools wrong, tell me in the comments and I'll fix it.
