Meser10 MCP server

Meser10 MCP Server

Connect the Meser10 email & SMS platform to any MCP client (Claude, Cursor, or your own agent).

תיעוד בעברית, כולל התקנה מודרכת: https://www.meser10.co.il/features/mcp-server/

Listed in the official MCP Registry since 19 September 2026 as io.github.meser10/meser10-mcp (v1.0.2, MIT). Verify independently, no account needed:

https://registry.modelcontextprotocol.io/v0/servers?search=meser10

Two Israeli email/SMS marketing platforms appear in the official registry. This is the only one of the two published as open source and installable as a package; the other is a remote endpoint with no repository and no package.

Tools are generated from the live WSDL. Nobody hand-writes 61 tool definitions here, which means the server covers every API capability by construction and does not drift when the platform ships a new operation.

Quick start

export MESER10_API_KEY=...      # issued in the Meser10 UI
export MESER10_USER_ID=...      # your account number - optional, see below
npx @meser10/mcp-server

MESER10USERID is optional at start-up. 17 of the 61 operations are authenticated by the key alone; the other 44 carry an explicit account number, and those fail with a clear message if it is not set. Set it unless you know you only need the first group. The account number is an identifier, not a secret - it is visible in the Meser10 UI.

Claude Desktop / Claude Code:

{
  "mcpServers": {
    "meser10": {
      "command": "npx",
      "args": ["-y", "@meser10/mcp-server"],
      "env": { "MESER10_API_KEY": "...", "MESER10_USER_ID": "..." }
    }
  }
}

Safety model

The server starts read-only. Nothing that spends money, messages a real person, or deletes a record is reachable until you opt in.

Two more guards:

than the cap. A model that misreads a prompt cannot mail your whole list.

• MESER10MAXRECIPIENTS (default 100) refuses any single send that targets more addresses

schema and filled in by the server. A model cannot see, guess, or leak them. CLoginInfo does accept UserName/Password, and this server deliberately never populates them - ApiKey only.

• Credentials are injected, never exposed. oLogin and iUserID are stripped from every tool

The one thing to know about errors

Every operation returns HTTP 200, including failures. Success lives in the Result field of CCallResult, not in the status code. This server reads Result, throws on anything that is not Success or PartialSuccess, and attaches a remedy:

LoginFailed: bad key - MESER10_API_KEY was rejected. Reissue the key in the Meser10 UI and restart.

PartialSuccess is surfaced as a warning rather than silent success, because it means some records in a batch did not land.

Design notes

Legacy variants are hidden. The contract exposes five Ex/Ex2 families (15 operations for 5 capabilities). Offering all of them makes a model choose between near-identical tools and pick wrong. The richest variant is exposed; the rest are hidden behind MESER10EXPOSELEGACY=true.

Names are written for callers. GetGroupsList is what the platform calls it. list_groups is what a developer reaches for. The underlying operation name is always in the description, so nothing is hidden.

Hungarian prefixes become type hints. saGroups is an array of strings, eLang is an enum, iUserID is an int. The generator uses that to produce better schemas and human titles.

Troubleshooting

Shortened. The full README is on GitHub.