MCP Server — Sealevel Docs

Prerequisites

You need a Sealevel API key. Sign in, then generate one from the Dashboard.

Add to Claude Code

Bash

claude mcp add --transport http sealevel https://mcp.sealevel.tech/mcp \
  --header "Authorization: Bearer slm_YOUR_KEY"

Replace slm_YOUR_KEY with your API key. Claude Code picks it up immediately.

Add to Cursor

Open Cursor Settings → MCP Servers, add:

JSON

{
  "mcpServers": {
    "sealevel": {
      "url": "https://mcp.sealevel.tech/mcp",
      "headers": {
        "Authorization": "Bearer slm_YOUR_KEY"
      }
    }
  }
}

Add to Windsurf

Open Windsurf Settings → MCP, add:

JSON

{
  "mcpServers": {
    "sealevel": {
      "url": "https://mcp.sealevel.tech/mcp",
      "headers": {
        "Authorization": "Bearer slm_YOUR_KEY"
      }
    }
  }
}

Add to OpenAI Codex

Add to your project's .codex/config.json:

JSON

{
  "mcpServers": {
    "sealevel": {
      "url": "https://mcp.sealevel.tech/mcp",
      "headers": {
        "Authorization": "Bearer slm_YOUR_KEY"
      }
    }
  }
}

Tools exposed

slm_chat — ask a Solana/Anchor question
slm_decode_error — look up an error code
slm_explain_tx — explain a transaction by signature
slm_migrate_code — migrate old Anchor code to 0.30+
slm_review_code — security + deprecation review

Prompts + resources

Slash command in Claude Code:

/mcp__slm__security-review — security audit for Anchor code (checks signer validation, owner checks, overflow, PDA collisions, close constraints)

Resources: solana://errors (complete error table), solana://system-prompt (Sealevel guardrails).