Koskamo

Promptster MCP

Promptster MCP enables AI coding assistants to programmatically test, compare, and benchmark prompts across multiple AI providers. It supports tools for testing prompts, comparing outputs, retrieving usage statistics, managing scheduled tests, and exporting data, facilitating cost optimization and quality assurance in AI development workflows.

Endpoint and access

OAuth sign-in: the first time you connect, your client opens the vendor's own authorization prompt in a browser.

Promptster MCP logo, by PromptsterCommunity listingStreamable HTTPOAuth sign-inEndpoint checked 2026-11-06Published by Promptster
You need:Bearer token using Promptster API key (pk_live_* or pk_test_*)
MCP endpoint (Streamable HTTP)
https://www.promptster.dev/mcp
Vendor documentation

Checks and signals

Each line is separate evidence, not a trust score.

  • Passed Endpoint answered the live check ·
  • Availability 1 of 1 checks passed in 30 days

What you can do with it

  • Test prompt effectiveness across multiple AI providers
  • Compare model response quality, speed, and cost
  • Retrieve usage statistics and credits
  • Manage and run scheduled automated regression tests

Source and maintenance

Community listingRegistry 1.0.0
mcp-registry: io.github.promptster-dev/promptster@1.0.0Source repositoryProject website
Maintenance checked

Tools

Reported by the attributed source; not independently observed by Koskamo.

No tool definitions available.

90-day uptime

A lightweight connection check about every six hours, sampled on hosts with many listings. It shows the server answered, not that its tools work.

Too few checks for a percentage yet (2 of 2 answered).

  1. 2026-11-07: 2 of 2 checks answered

30-day availability

Aggregated from read-only remote checks; this is not a tool-execution or security guarantee.

Successful checks
1 of 1 (100%)
Average latency
320 ms
95th percentile latency
320 ms

Maintenance history

Public check and source-refresh events. Editorial and ownership records remain private.

  • · probe · passed · 320 ms · metadata changed · refuses unauthenticated initialize (HTTP 401)

Connect from your client

Each snippet registers the same endpoint; pick the client you use.

This server is operated by the named third party. Listing and endpoint checks are not an endorsement or a security audit. Review the operator's permissions, terms, and data handling before connecting. How listings are checked and corrected.

Claude Code

Run this once in a terminal. It registers the remote server. Use --scope project to write .mcp.json for the repo.
Claude Code configuration
claude mcp add --transport http promptster-mcp https://www.promptster.dev/mcp

Codex

Run this once. Codex stores MCP servers in ~/.codex/config.toml (or .codex/config.toml in a trusted project).
Codex configuration
codex mcp add promptster-mcp --url https://www.promptster.dev/mcp

Cursor

Merge this server into .cursor/mcp.json in your project, then enable promptster-mcp in your MCP settings.
Cursor configuration
{
  "mcpServers": {
    "promptster-mcp": {
      "url": "https://www.promptster.dev/mcp"
    }
  }
}

Cline

Merge this into cline_mcp_settings.json (Cline → MCP Servers → Configure).
Cline configuration
{
  "mcpServers": {
    "promptster-mcp": {
      "type": "streamableHttp",
      "url": "https://www.promptster.dev/mcp",
      "disabled": false
    }
  }
}

VS Code

Merge this server into .vscode/mcp.json. Use MCP: List Servers to start promptster-mcp and inspect its tools.
VS Code configuration
{
  "servers": {
    "promptster-mcp": {
      "type": "http",
      "url": "https://www.promptster.dev/mcp"
    }
  }
}

Gemini CLI

Run this once. It writes .gemini/settings.json in the current project; pass --scope user for ~/.gemini/settings.json.
Gemini CLI configuration
gemini mcp add --transport http promptster-mcp https://www.promptster.dev/mcp

Claude Desktop

Open Claude Settings > Connectors > Add custom connector, enter this server URL and enable it for the conversation. This is a manual remote-connector handoff, not a desktop JSON configuration.
Claude Desktop configuration
https://www.promptster.dev/mcp

Windsurf

Merge this into ~/.codeium/windsurf/mcp_config.json, then refresh MCP in Cascade. Windsurf remote servers use serverUrl, not url.
Windsurf configuration
{
  "mcpServers": {
    "promptster-mcp": {
      "serverUrl": "https://www.promptster.dev/mcp"
    }
  }
}

Let your agent find its tools

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